Global Spine Journal

Knowledge of important clinical predictors of surgical outcome can provide decision support to surgeons and enable them to appropriately manage their patients' expectations. This study aims to determine the most important global clinical predictors of surgical outcome in patients undergoing surgery for CSM, based on data from two multicenter prospective studies.

A total of 743 surgical patients with CSM participated in either the CSM-North America or CSM-International study. The model was developed to distinguish between patients with mild myelopathy postoperatively (mJOA ≥ 16) and those with substantial residual neurological impairment (mJOA < 16). Univariate analyses were performed to evaluate the relationship between outcome and various clinical predictors. Multivariate logistic regression was used to formulate the final prediction model.

Univariate analyses demonstrated that the odds of achieving a score ≥ 16 decreased with the presence of certain symptoms, including impaired gait; the presence of certain signs such as lower limb spasticity; positive smoking status; a higher comorbidity score; more severe preoperative myelopathy; and older age. The final prediction model included age (OR = 0.97, p = 0.0017), duration of symptoms (OR = 0.88, p = 0.049), smoking status (OR = 0.51, p = 0.0018), impairment of gait (OR = 1.94, p = 0.0168), broad-based unstable gait (OR = 1.75, p = 0.0133), baseline severity (OR = 1.23, p < 0.0001), and comorbidity score (OR = 0.84, p = 0.0030).

Patients are more likely to achieve a score ≥ 16 if they are younger, have a shorter duration of symptoms, are less severe preoperatively, do not smoke, and do not have comorbidities or evidence of gait dysfunction.

Shoulder asymmetry (SA) has been reported to be a frequent (39%) problem after fusion of the main thoracic (MT) curve in patients with nonstructural proximal thoracic (PT) curves (Lenke Type 1 and 3). The purpose of this study was to analyze factors related to shoulder asymmetry and efficacy of traction X-ray under general anesthesia (TrUGA) in predicting postoperative shoulder asymmetry.

A total of 137 (128 female patients, 9 male patients) consecutive patients (average age: 14.2 [11–17]) with Lenke Type 1 and Type 3 curves and preoperative right shoulder elevation (RSE) with (-) T1 tilt were included in this study. Radiographic analysis included preoperative, postoperative, and follow-up AP standing, supine bending, and TrUGA. Magnitudes of curves, T1 tilt, clavicle angle, shoulder height, first rib angle (FRA), and second rib angles (SRA) were measured as shoulder asymmetry parameters. Left or right shoulder elevation > 1 cm is accepted as shoulder imbalance. SRS-22r and shoulder balance questionnaires were also analyzed at follow-up.

Mean age was 13.96 years (11–17) and average follow-up was 5.21 years (2–12). A total of 107 patients had UIV at T2, 17 patients had UIV at T3, and 13 had UIV at T4. Average correction rates were 69.12% for PT curve, 82.4% for MT curve, and 73.5% for TL/L curve. Postoperatively, 101 patients (73%) had balanced shoulders. A total of 17 patients (12.4%) had LSE and 20 patients (14.6%) had RSE postoperatively. Incidence of LSE was 8.4% (9 patients) for UIV at T2, 29.4% (5 patients) for UIV at T3, and 23.1% (3 patients) UIV at T4. Higher percentage of MT correction was correlated with LSE (p = 0.043). Shoulder height, clavicula angle, T1 tilt, FRA, and SRA were correlated in TrUGA and at follow-up. Preoperatively, 83% of the patients and at final follow-up 7.8% patients thought they had shoulder asymmetry. Av SRS-22r score was 4.32 (2, 96–5) and was similar in patients who had shoulder asymmetry (4, 36) versus no asymmetry (4, 29).

Risk factors for shoulder asymmetry in patients with nonstructural PT curves are higher correction percentage of MT and extension of instrumentation up to T3 at PT curve. Extension of fusion up to T2 did not always prevent shoulder asymmetry in patients with nonstructural PT curves. Shoulder asymmetry parameters in TrUGA are helpful in predicting postoperative shoulder asymmetry. HRQL scores are similar in patients with SA versus no SA.

Painful IVD degeneration affects the quality of life for millions of people, and it presents a major problem for direct and indirect global health care costs. A preclinical ex vivo screening platform is needed to study the relationship between mechanobiology, disc matrix composition, and metabolism in the context of degenerative disease. We therefore developed an ex vivo organ culture model that facilitates culture of intact human discs in a controlled dynamically loaded environment. The bioreactor is used in combination with a previously reported harvesting method, which maintains the integrity of the intervertebral discs by preserving the noncalcified part of the cartilage end plate and the entire annulus. Here, we determine IVD tissue integrity and cell viability in the system, and investigate the suitability toward cell supplementation for tissue repair.

A total of nine lumbar IVDs from seven individual donors were obtained through organ donations via Transplant Québec. The spines were assessed by X-ray to evaluate degree of degeneration and six discs were isolated from four donors as previously described. Overall, 10⁶ primary fluorescently labeled allogeneic NP cells from three separate donors were seeded per 1 mL of thermogelling hyaluronic acid hydrogel (HA-pNIPAM). Approximately, 250 µL of cell/gel mixtures were injected laterally into the NP region of isolated discs. IVDs with the newly transplanted cells were transferred to the bioreactors and were loaded with 0.1 to 0.6 MPa cyclic loads for two periods of 2 hours/day. The dynamic compressive load periods were interrupted by recovery periods of 6 hours and 14 hours, respectively, under 0.1 MPa static loads. The scheme was repeated for 3 or 7 or 14 consecutive days. After loading, portions of nucleus pulposus and annulus fibrosus were excised and analyzed via LIVE/DEAD assay, and smaller sections were visualized using a laser-scanning confocal microscope. The proportion of viable cells was quantified.

Our culture system maintains > 80% cell viability of the resident IVD cells and shows no signs of adverse effects in the extracellular matrix after more than 14 days of dynamic culture. Allogeneic NP cells were successfully transplanted in freshly isolated human discs. The transplanted cells were found dispersed throughout the nuclear and annular regions and displayed maintained viability after up to 14 days of dynamic culture.

This study shows that it is feasible to culture human IVDs under dynamic loading for more than 14 days while maintaining cell viability, tissue homeostasis, and integrity. It also presents a preclinical ex vivo screening platform where cell-based therapies, utilizing isolated disc cells or stem cells can be tested in combination with various injectable hydrogels. In addition, the effect of load magnitude and frequency, growth factors, O₂ tension, glucose levels, and bioactive therapeutics can be evaluated. The bioreactor can also be used to evaluate loss or gain of mechanical function as a result of biological changes. Such knowledge is important for determining the value of cell/hydrogel injections and patient advisement on physical activities following a biological repair procedure.

The perioperative outcomes and adverse events of minimally invasive surgery (MIS) for lumbar fusion remain unclear. The purpose of this systematic review and meta-analysis is to summarize the perioperative outcomes and adverse event rates for MIS transforaminal or posterior lumbar interbody fusion (TLIF/PLIF) compared with traditional open midline techniques.

A systematic review of Medline, EMBASE, PubMed, Web of Science, and Cochrane databases were performed. A hand search of reference lists was performed. Studies were reviewed by two independent assessors to identify randomized controlled trials or comparative cohort studies including ≥ 10 patients undergoing MIS or open TLIF/PLIF for degenerative lumbar spinal disorders and reporting at least one of the following: clinical outcome measure; perioperative surgical performance or outcome measure; radiographic outcome; or adverse events. Study quality was assessed using the GRADE protocol. When appropriate, a meta-analysis of outcomes data was conducted.

The systematic review and reference list search identified 3,306 articles, with 26 meeting study inclusion criteria. All studies, including one randomized controlled trial, were of low or very low quality. No significant difference regarding age, gender, surgical levels, or diagnosis was identified between the two cohorts (n = 856 MIS/n = 806 open). Meta-analysis revealed changes in the perioperative outcomes of mean estimated blood loss, time to ambulation, and length of stay favoring an MIS approach by 260 mL (p < 0.00001), 3.5 days (p = 0.0006) and 2.9 days (p < 0.00001), respectively. Operative time was not significantly different between the surgical techniques (p = 0.78). There was no significant difference in surgical adverse events (p = 0.97); however, MIS cases were significantly less likely to experience medical adverse events (RR [95% CI] MIS vs. open = 0.39 [0.23–0.69], p = 0.001). No difference in nonunion (p = 0.97) or reoperation rates (p = 0.97) was observed. Mean Oswestry Disability Index scores were slightly better in the patients with MIS at a median follow-up time of 24 months (mean difference MIS [n = 346] vs. open [n = 346] = 3.32, p = 0.001).

The quality of the current comparative evidence is low to very low with significant inherent bias. The result of this quantitative systematic review of clinical comparative effectiveness research examining MIS versus open TLIF/PLIF for degenerative lumbar pathology suggests equipoise in patient reported clinical outcomes. Furthermore, meta-analysis of adverse event data suggests equivalent rates of surgical complications with lower rates of medical complications in patients undergoing MIS TLIF/PLIF compared with open surgery.

Schwannomas are benign neurogenic tumors, with a reported annual incidence between 0.3 and 0.5 per 100,000 people, mainly in their 4th and 5th decades, with no gender preference. Together with neurofibromas, they account for up to 30% of all intraspinal tumors. They usually present as a solitary slow-growing oval, lobulated and encapsulated mass, arising eccentrically from the nerve root sheath. Symptoms and signs are related to root and/or cord compression and may slowly progress with tumor growth. Total resection is the gold standard for patients with initial sensory or motor deficits. Local recurrence is reported to be around 5% and it usually occurs several years after the surgery. The objective of this study was to analyze a multicenter database of patients operated for spine schwannomas to identify risk factors for local recurrence.

Retrospective analysis of 169 patients (age > 18 years) from the AOSpine Multicenter Primary Spinal Tumors Database, who underwent surgery for a spine schwannoma (48% female, mean age at diagnosis 46.6 ± 15.31 years, mean follow-up 50.68 ± 39.23 months). Rates of tumor recurrence and time to recurrence were quantified. The predictive value of various clinical factors, including age, gender, tumor size, affected spinal segments, type of surgery, and extent of disease as defined by the Weinstein-Boriani-Biagini (WBB) classification system, was assessed. Descriptive statistics and univariate analysis was performed.

The mean number of affected levels per patient was 1.85 ± 0.86 and 82.84% of them were located in the mobile spine (41.42% between L1 and L5). According to the WBB classification, 47.12% of the tumors had an intradural extension, while 31.73% were both intra- and extradural and the mean number of affected sectors was 4.49 ± 3.61. Regarding the surgery, 69.75% of the patients had an en bloc resection, mainly via a posterior approach (74.84%). Nine patients experienced local recurrence (5.3%) at a time range of 81 to 1,518 days after the surgery. These patients were on average younger (39.33 ± 15.58 vs. 47.01 ± 15.29), although this relationship did not reach significance (HR = 0.97, p = 0.16). Overall, 13, 10, and 7% of patients with cervical, sacral, and lumbar disease respectively, experienced tumor recurrence compared with 0% of thoracic patients (p = 0.18). The location of the tumor (p = 0.25), whether epidural, intradural or both, and the number of WBB sectors involved (HR = 1.03, p = 0.79) were not significantly related to recurrence. The actual size of the tumor was significantly larger in patients with recurrence (6.97 ± 4.66 vs. 3.81 ± 3.34) (HR = 1.16, p = 0.028), with the extent in the cranial-caudal direction posing the greatest hazard (HR = 1.324, p = 0.0018). With respect to surgical technique, patients receiving a complete resection (3.6%) had a significantly lower risk of recurrence than those treated with an intralesional subtotal procedure (13.9%, p = 0.047).

Local recurrence after schwannoma resection appears to be determined mainly by the size of the tumor and the extent of the surgical resection.

The etiology of adolescent idiopathic scoliosis is still unclear and the true mode of inheritance has yet to be established. From the Danish twin cohort concordance rates in monozygotic twins have previously been reported to be 0.13 and in dizygotic twins 0. Studies on concordance in twin pairs provide a basis for analyzing the influence of genetic versus environmental factors. In this study, we wanted to validate if self-reported scoliosis is a valid method to establish incidence and concordance rates in a twin population.

All 46,418 twins registered in the Danish Twin Registry born from 1931 to 1982 were sent a questionnaire, which included questions about scoliosis. The questionnaire was returned by 34,944 (75.3%) representing 23,204 pairs.

A total of 548 individuals representing 274 complete twin pairs, where at least 1 has self-reported scoliosis were invited to a clinical and a radiologic examination. Zygosity was established by genetic testing.

A total of 182 individuals (33.2% of the cohort) participated. Overall, 128 of these individuals had self-reported scoliosis. The total number of participants consisted of 91 twin pairs, where one or both twins had scoliosis and 36 individuals whose twin did not want to participate.

Overall, 35 individuals (27.3%) of the 128 participants with self-reported scoliosis presented a clinical and radiological confirmed curve. Of these were 5 twin pairs (four monozygotic pairs and one dizygotic pair) with scoliosis in both twins and 16 twin pairs with scoliosis in only 1 twin and 9 individuals where only one twin participated.

Calculating concordance in twins with curves greater than 10 degrees, we found that the pairwise concordance rate was 0.4 (range, 0.12–0.74) for monozygotic and 0.05 (range, 0.01–0.25) for dizygotic twin pairs, probandwise concordance was 0.45 for monozygotic and 0.1 for dizygotic pairs.

Self-reported scoliosis in a Danish twin population is not a valid method to establish the true concordance rates. Although it is not statistically significant the differences in monozygotic and dizygotic pairs indicate that hereditary parameters have an impact.

ICF is developed as a generic system for classification of function. The ICF framework is often used to describe functional capacity of the low back patient (LBP) referred for rehabilitation but the score describing the level of capacity for the individual patient is not used in daily practice. The purpose of the presented study was to implement and validate the core set for LBP used as a framework for reporting information and to evaluate whether information reported in self-administered questionnaires (PRMOs) can be used to fill in parts of the ICF.

LBP referred to the University Hospital, Aarhus, Denmark, for further diagnostic procedures were included in the cohort. Overall, 80 patients were described according to the framework of ICF and scored according to the LBP brief core set.¹ Of the whole group, 28 (35%) were referred to a rehabilitation center. At inclusion and at the rehabilitation center, the team treating the patient did the ICF scoring at inclusion and at 4 weeks' follow-up. In addition, the patients filled in questionnaires; Roland Morris and SF-36. The correlation between the registration in the context of ICF at one side and RM/SF-36 at the other was estimated to validate whether a self-administered questionnaire is as valid to describe functional capacity as an interview by the treating physician.

The functional capacity evaluated by the treating team at first gradient for each of 35 domains in ICF correlated with information obtained from the self-administered questionnaires RM and SF-36. Valid information can be translated from RM and SF-36 and the time used to complete the ICF form can be reduced. A dynamic model describing the functional capacity of the individual patient in the terms of ICF filled in by self-administered questionnaires will be demonstrated and the need of supplementary information obtained by interview will be highlighted.

ICF can be used as a framework for information used in a rehabilitation program. The corset has to be defined in detail, as well as the approach to the scoring system, before the information given is reliable as well as clinical important in any clinical setting. PROMs can be used to fill in part of the ICF core set. A dynamic database is a valuable tool facilitating the reporting process.

Reference

Stucki G, Ewert T, Cieza A. Value and application of the ICF in rehabilitation medicine. Disabil Rehabil 2002;24(17):932–938

Despite the high number of surgeries performed for spondylolisthesis, the basic epidemiology of lumbar spondylolisthesis in the general population is not well known. The aim of this study was to clarify the association of lumbar spondylolisthesis with symptomatic lumbar spinal stenosis (LSS) in a population-based cohort study with participants representing the general Japanese population.

This cross-sectional study included 938 participants (308 men, 630 women; mean age, 67.3 years; range, 40–93 years). Lumbar radiographs were obtained for all the participants, with lumbar spondylolisthesis classified as a slip of more than 5% on the lateral view. The diagnosis for symptomatic LSS required the presence of both leg symptoms and radiographic lumbar spinal stenosis on magnetic resonance imaging. The presence of symptomatic LSS was compared between participants with and those without lumbar spondylolisthesis using statistical analysis. Furthermore, we clarified the association between the amount of slippage and the presence of neurogenic claudication.

The prevalence of spondylolisthesis at any level was 15.8% overall, 13.0% in men and 17.1% in women, with no significant difference between genders. The prevalence of symptomatic LSS was 9.0% overall, 9.4% in men, and 8.7% in women. Logistic regression analysis after adjustment for age, gender, and BMI showed that there existed a significant association of spondylolisthesis with symptomatic LSS overall. (OR: 2.07, 95% CI: 1.20–3.44). While, among participants with L4 anterior spondylolisthesis, the mean percentage slip in those with neurogenic claudication was 14 ± 1.2% and those without was 14 ± 0.5%, with no significant difference.

This population-based cohort study revealed that there was a significant association of spondylolisthesis with neurogenic claudication, although the amount of slippage was not related to the presence of neurogenic claudication.

The incidence of traumatic cervical spine fractures (CS-fx) in the general population is largely unknown. Former published data describe the incidence in different subpopulations, such as trauma center patients, head injury patients, osteoporotic patients, and military populations. Norway is a small country in Northern Europe with 5 million inhabitants. All acute traumatic cervical spine injuries are treated in government- owned public health care. The aim of this study was to estimate the incidences of CS-fx and of open surgical fixation of CS-fx in the Norwegian population.

The Norwegian Patient Register (NPR) is an administrative database that contains activity data from all Norwegian government-owned hospitals and outpatient clinics. Reporting to NPR is mandatory and linked to the funding of health services. The diagnoses and procedures are coded according to the International Statistical Classification of Diseases and Related Health Problems (ICD-10) and the NOMESCO Classification of Surgical Procedures (NCSP), respectively. We retrieved information on all CS-fx between 2009 and 2012 from the NPR. Updated information on the date of death is included through routine linkage to the General Register Office.

Between 2009 and 2012, a total of 2,963 patients had one or more CS-fx. The median age was 54 years, and 69% of the patients were male. The incidence of CS-fx was 15.0/100,000/year. A total of 19% of the patients were treated with open surgery, resulting in an estimated incidence of 2.9/100,000/ year for surgery for CS-fx in the Norwegian population. The 1- and 3-month mortality rates were 4 and 6%, respectively.

To the best of our knowledge, this is the first registry-based study of the epidemiology of CS-fx in a general population. Our estimate of the incidence of CS-fx in the total Norwegian population was 15/100,000/year. The incidence of open surgery for CS-fx in the Norwegian population was estimated to be 2.9/100,000/year.

Recently, the field of outcome assessment for patients undergoing spinal surgery has become the focus of investigation. Health-related quality of life outcome measures are fundamental to our understanding of the impact of surgical intervention on patients. Major spine academic groups have placed increasing emphasis on the use of HRQOL outcome measures, and this is no more obvious that in the requirements for abstract submissions to annual scientific meetings. The purpose of our study was to analyze the use of clinical outcome measures in abstracts accepted to the North American Spine Society (NASS) and Canadian Spine Society (CSS) annual meetings from 2010 to 2013 inclusively. We investigated the disease populations studied, the HRQOL outcome measures used, determined whether those measures had been validated in the specific patient population, and finally, whether the outcome measures used could be linked to the current WHO International Classification of Functioning, Disability, and Health (ICF).

Accepted abstracts to NASS and CSS annual meetings from 2010 to 2013 were read. The frequency of abstracts containing clinical outcome measures and the frequency of validated versus non-validated outcome measures were analyzed. A systematic literature search was then performed using the Cochrane Library Database, PubMed, and the NASS evidence-based clinical guidelines. The concepts contained in the items of the 10 most commonly used outcome measures were selected and linked to the most specific ICF categories. Each concept of the outcome measure was linked to the ICF in a step-wise fashion.

A total of 1,663 abstracts were read from the CSS and NASS from 2010 to 2013 inclusively. Of the abstracts accepted to CSS and NASS, 71 and 53% contained validated outcome measures, respectively. The 10 most commonly used outcome measures were the ODI, VAS, NDI, Eq. 5D, mJOA, AIS, and RMDQ. A total of 40 spinal conditions/surgical approaches were described among the 10 most commonly used health-related outcome measures. The NASS evidence-based clinical guidelines provided validity recommendations for spondylolisthesis, radiculopathy, and spinal stenosis. The Cochrane Library Database published systematic reviews for disc arthroplasty, degenerative disc disease, vertebral fractures, spinal fusion, disc replacement, back pain, cervical spondylotic myelopathy, and thoracolumbar burst fractures. All validity analyses for the remaining conditions/surgical approaches were found through PubMed and Google Scholar. All of the concepts for each outcome measure were linkable to the ICF.

According to this study, all of the 10 most commonly used outcome measures in abstracts accepted to CSS and NASS from 2010 to 2013 inclusive were validated in the field of spinal surgery. There is, however, still a need for one universal database to determine which outcome measures would be most useful for a given spinal condition or surgical approach. All of the 10 most commonly used outcome measures were linked to the WHO ICF. This provides evidence that over the past 4 years, researchers and clinicians in spinal surgery have identified the importance of utilizing validated HRQOL outcome measures as their health predictors.

This study aims to evaluate the epidemiologic characteristics of patients with diagnosis of nontraumatic spinal cord injury (NTSCI) in a tertiary care hospital in Latin America.

Patient and Methods: Retrospective single center study including 122 patients who were discharged between January 2005 and December 2012 from their initial inpatient rehabilitation after the onset of NTCSI confirmed by clinical and image studies. Descriptive statistics were performed for demographic characteristics, etiology, and the degree of neurological injury.

From 585 patients admitted with diagnosis of spinal cord injury during the study period, 122 had NTSCI, the prevalence of NTSCI in our center was 20.9%. Of these 122 patients, 35 patients were excluded for the following different reasons: incomplete patient data in 22, 9 patients with cerebrovascular disease associated, and 4 patients with associated lesions below L2 level. Overall, 87 patients were included in the final statistical analysis, 48% male and 35.6% female. The mean age was 45.2 years, marital status of patients was 42.5% married and 29% single. Overall, 34% of patients had elementary education and 35.6% of patients were unemployed before NTSCI occurred. The lesions were classified using the American Spinal Injury Association Impairment Scale (AIS) results was AIS D (motor incomplete) in 40.22%, C (motor incomplete) in 14.94%, B (sensor incomplete) in 19.54%, and A (complete) in 24.13% of patients. The most frequent etiology was tumoral cord compression in 50 patients (57.4%) in 47 of these patients lesions were metastatic (94%) and 3 (6%) primary bone tumors. The second most frequent etiology was cervical or thoracic degenerative disease causing myelopathy in 17 patients (19.5%) followed by transverse myelitis in 9 patients (10.3%), and vertebral osteomyelitis in 7 patients (8%), arteriovenous malformations was present in 2 patients (2.29%), and undetermined in 2 patients (2.29%).

The results confirm that nontraumatic spinal cord injury represents a significant proportion of the population with spinal cord injury with a prevalence of 20.9%. Males with median age of 45 years are more frequently affected. The most common etiology is metastatic spinal lesion in 54% of patients. Most of the neurological lesions are classified as incomplete (75.87%) using the AIS scale. Epidemiological data of spinal cord injury is needed for an effective implementation of primary prevention strategies, appropriate management programs, and allocations of health resources in the field of spine surgery and rehabilitation care.

Pedicle screws are routinely used in contemporary spinal surgery. Screw misplacement is however correlated with potential adverse events. The goal of this study is to perform an economic evaluation looking specifically at the misplaced screws leading to reoperation secondary to neurological deficits or biomechanical concerns.

A patient-level data cost-effectiveness analysis from the hospital perspective was conducted based on a single center observational study of prospectively collected data to determine the value of a navigation system coupled with intraoperative 3D imaging (O-arm Imaging and the StealthStation S7 Navigation Systems, Medtronic, Louisville, CO) in adult spinal surgery. The data source was a consecutive series of patients treated with the aid of computer-assisted surgery (treatment group) compared with a matched historical cohort of patients treated with conventional methods (control group). The primary effectiveness measure studied was the number of reoperations for misplaced screws.

A total of 5,132 pedicle screws were inserted in 502 patients during the study period; 2,682 screws in 253 patients in the treatment group, and 2,450 screws in 249 patients in the control group. Overall accuracy rates were 95.2% for the treatment group and 86.9% for the control group. Two patients (0.8%) required a revision surgery in the treatment group (both within the same admission) compared with 15 patients (6%) in the control group (nine within the same admission and six within 1 year during a subsequent admission). Costs of the different alternatives were assessed based on the annuitization of capital expenditures method. Using this methodology, an incremental cost effectiveness ratio of $15,961/reoperation avoided was calculated for the computer-assisted surgery group. On the basis of a reoperation cost of $12,618, this new technology becomes cost saving for centers performing more than 254 instrumented spinal procedures per year.

Computer-assisted spinal surgery has the potential to reduce reoperation rates and thus to have serious cost-effectiveness implications. High acquisition and maintenance costs of this technology can be offset by equally high reoperation costs. Our cost-effectiveness analysis showed that for high-volume centers, this technology is economically justified.

In the past 10 years, the importance of the sagittal shape of human pelvis has been pointed out by the orthopedists. However, most studies were defined in Western and Korean populations. It is unclear whether these characteristics of Chinese spinopelvic sagittal alignment differ from those of western and Korean populations. In addition, the predictive equation of lumbar lordosis remains unclear. This study described normal types of spinopelvic sagittal alignment in Chinese asymptomatic subjects, and investigated a prediction equation of lumbar lordosis from selective spinal and pelvic sagittal parameters.

This was a prospective radiological analysis using full-spine standing lateral radiographs of Chinese volunteers. A total of 171 volunteers (94 males and 77 females; mean age, 23 years [range, 18–28 years]) participated. Pelvic and spinal parameters were measured according to geometric characteristics. The Pearson correlation test was calculated, regression analysis was running with the lumbar lordosis (predicted variable), and the other spinal and pelvic parameters (predictor variables), to determine the best sets of predictors to include in the model.

Mean pelvic incidence was 44.6 ± 9.5 degrees, significantly less than that reported in Western subjects. The volunteers were classified into four types according to the location of their apex of total lumbar lordosis. As the apex of total lumbar lordosis moved cranially, lordosis tilt decreased, whereas lower lumbar lordosis, pelvic incidence, sacral slope, and the number of vertebral bodies included in the lower lumbar lordosis increased. On the basis of the pelvic incidence, total lumbar lordosis predictive equation was 0.639 PI + 20.593 degrees. Preliminary prediction of lower lumbar lordosis was PI-10 degrees.

The sagittal alignment of Chinese population could be classified into four types, and was different from that of Caucasian. Lower lumbar lordosis comprised most of total lumbar lordosis, the role of pelvic incidence in determining the sagittal curve was mainly through the adjustment of lower lumbar lordosis. Using regression analysis, total lumbar lordosis could be precisely predicted in asymptomatic subjects. To optimally plan surgery for spinal deformity, the prediction of postoperative lower lumbar lordosis curvature was equally important as that of total lumbar lordosis.

Variations in cervical muscle cross-sectional area (CSA) and composition, particularly of the multifidus muscle, have been reported in patients with chronic neck pain. However, few studies have reported on the reliability of such muscle measurements and there remains no standard protocol for tissue segmentation. Therefore, the purpose of this pilot study was to provide a detailed muscle measurement protocol and determine the reliability of associated cervical muscle size and composition measurements using an open-source image analysis software (ImageJ).

Cervical magnetic resonance images of 10 individuals with spinal stenosis were selected from an internal database. Muscle CSA and functional cross-sectional area (FCSA, fat-free area) measurements of the multifidus, semispinalis cervicis, semispinalis capitis, and splenius capitis were acquired bilaterally from axial T2-weighted magnetic resonance image from C2–C3 to C6–C7 levels. All measurements were repeated twice, at least 5 days apart and the assessor was blinded to all earlier measurements.

The reliability for the upper (C2–C3 and C3–C4) and lower cervical levels (C4–C5, C5–C6, and C6–C7) was assessed separately. The intrarater reliability measurements were comparable between muscles and spinal levels. The intraclass correlation coefficient (ICC) for the CSA measurements varied between 0.79 to 0.97 at C2–C4 and 0.75 to 0.91 at C4–C7. The reliability was similar for the FCSA measurements and varied between 0.73 to 0.93 at C2–C4 and 0.78 to 0.90 at C4–C7.

The results of this pilot study suggest that the proposed method to investigate cervical muscle size and composition is reliable, with moderate-to-excellent reliability across cervical muscles and vertebral levels.

To investigate whether the posterior cranial fossa (PCF) morphology in Chiari I malformation without syringomyelia (CMI only) is different from that in Chiari I malformation with syringomyelia (CMI-S).

A total of 14 patients with CMI and without syringomyelia constituted the CMI-only group, whereas 30 patients with CMI and syringomyelia were assigned to the CMI-S group. Another cohort of 30 age-matched asymptomatic adolescents was enrolled to serve as the control group. Six measurements were evaluated and compared between these three groups from T1-weighted magnetic resonance (MR) imaging, including the length of the clivus (AB), the anteroposterior diameter of the foramen magnum (BC), the length of the supraoccipital (CD), the anteroposterior diameter of the posterior fossa (DA), the posterior fossa height (BE), and the clivus gradient (∠α). The PCF morphology in relation to syrinx severity was also investigated.

Compared with the normal controls, the AB, CD, DA, BE, and ∠α were significantly larger in the CMI-S group. Similar changes in AB, CD, DA, and BE were also demonstrated in the CMI-only group, whereas the clivus gradient (∠α) was found to be relatively normal when compared with the control group. A significantly decreased clivus gradient was observed in the CMI-S groups compared with CMI-only group. In addition, the clivus was significantly flattened in patients with a distended syrinx in comparison to those with a nondistended syrinx.

Small sizes of the posterior fossa were detected both in CMI cases with and without syrinx. The clivus gradient served as the only morphologic difference in the PCF between CMI-S and CMI-only patients and was correlated with the severity of the syrinx, may support the theory that the restricted circulation of cerebrospinal fluid at the anterior paramedial subarachnoid space contributes to the formation of a syrinx.

Lumbar discectomy is one of the most common surgical procedures, with success rates greater than 80%. To better understand the meaning of a good outcome in lumbar disc herniation treatment, it is important to know how much the health care system or the patient need to pay to achieve a good result. The cost–utility studies are useful to evaluate the value of health care interventions. The objective of this study was to evaluate for the first time the cost-effectiveness of spine surgery in Latin America for lumbar discectomy in terms of cost per quality-adjusted life years (QALY) gained in Brazil.

Costs of medical treatment were recorded in 143 consecutive patients who underwent open discectomy for lumbar disc herniation. Direct medical costs comprised medical reimbursement and costs of hospitalization. Indirect costs were considered the disability losses. Utilities were estimated using SF-6D–derived utilities from a 12-month variation in SF-36. A 4-year horizon with 3% discounting was applied to health utilities estimates. Sensitivity analysis was performed by varying utility gain by 20%. The costs were expressed in Reais (R$) and American Dollars ($), at an exchange rate of 2.4:1.

Direct and indirect costs of open discectomy were estimated at an average of R$ 3.426,72 ($ 1,427.80) and R$ 2.027,67 ($ 844.86), respectively. The mean total cost of treatment was estimated at R$ 5.454,40 ($ 2,272.66) (± R$ 2.709,17/$ 1,128.82) The SF-6D utility gain was 0.0456 (95% CI: 0.03197–0.05923, p = 0.017) at 12 months. The 4-year discounted QALY gain was 0.176928. The estimated cost-utility ratio was R$ 30.828,35 ($ 12,845.14) per QALY gained. The sensitivity analysis showed a range of R$ 25.690,29 ($ 10,714.28)–R$ 38.535,44 ($ 16,056.43) per QALY gained.

Open discectomy is associated with a significant improvement in health utilities as measured by SF-6D. Open discectomy performed in the Brazilian Supplementary Health System provides a cost–utility ratio of R$ 30.828,35 ($ 12,845.14) per 1 quality-adjusted life year.

An interdisciplinary hybrid operating theater was established in June 2012 at the University of Ulm. A floor-based 3D flat panel robotic C-arm (Artis Zeego, Siemens, Germany) is connected to the operating table and the ceiling-based navigation system (BrainLab Curve, BrainLab, Germany). The robotic C-arm is controlled by the surgeon through a control panel mounted on the operating table in the sterile field. The large field of view of the flat panel C-arm allows visualization of the entire lumbar spine or pelvic ring with a single intraoperative 3D scan. This operating room is shared by four different disciplines (orthopedic surgery, neurosurgery, vascular, and cardiac surgery). This hybrid setup represents an advanced imaging and navigation system, and is the first of its type.

We included all orthopedic surgeries performed in the hybrid operating theater during the first year. All the cases were reviewed for postoperative complications.

A total of 92 cases in 91 patients were performed in the first year. Posterior stabilization of the spine was the most common procedure (57.6%) followed by sacroiliac screws (13%). Other procedures included tumor resection of the spine or pelvis, kyphoplasty, and fixation of acetabular and extremity fractures. Overall, 51.1% of the cases used navigation and 46.7% a minimally invasive technique. Complications included four postoperative seroma and two consecutive infections. All seroma and infections occurred in tumor resections. In large tumor resections, two neurological deficits were detected. Another patient developed dysphagia after fixation of an odontoid and atlas fracture.

None of the complications occurred because of the use of the hybrid operating theater instead of a conventional operating theater. The hybrid operating theater combines high quality, large field intraoperative imaging with advanced navigation. This results in a higher surgeon confidence in hardware placement and total tumor resection. The control panel mounted on the operating table enables the surgeon to operate this complex imaging device in the sterile field. The interdisciplinary use of the operating theater optimizes utilization.

There was a paucity of literature paying attention to the postoperative imbalance after pedicle subtraction osteotomy (PSO) or Smith–Petersen osteotomy (SPO) and natural evolution of the imbalance. This study aims to compare compensatory behavior of coronal and sagittal alignment following PSO and SPO for degenerative kyphoscoliosis.

A retrospective study was performed on 68 consecutive patients with degenerative kyphoscoliosis treated by lumbar PSO (25 patients) or SPO (43 patients) procedures at a single institution. Long-cassette standing radiographs were taken preoperatively, postoperatively, and at last, follow-up and radiographic parameters were measured. The LIV and level of osteotomy were compared between the patients with and without improvement.

Negative SVA was observed in PSO group postoperatively, implying an overcorrection of SVA. This negative SVA improved spontaneously during follow-up (p < 0.05). Coronal balance was found to worsen immediately post-op in the SPO group (p < 0.05). At the last follow-up, spontaneous improvement was observed in 15 patients and the average CB decreased to 16.35 mm. For the 15 patients with improved CB, fusion at L5 or above was more common compared with the 11 patients with persisted postoperative imbalance (p = 0.027), whereas no difference in term of levels of osteotomy was found (p > 0.05).

The overcorrection of SVA is more often seen in PSO group. The coronal imbalance is more likely to occur in SPO group. The postoperative sagittal imbalance often spontaneously improves with time. LIV at S1 or with pelvic fixation should be regarded as potential risk factors for persistent coronal imbalance in patients with SPO.

Various correction methods have been developed to treat severe rigid scoliosis. The anterior release was performed for many years to improve the flexibility of rigid scoliosis, however, the safety and efficacy of combined anterior/posterior approach were questioned by many authors. This study aimed to evaluate the efficacy and safety of two-stage posterior surgery for severe rigid scoliosis and to determine whether posterior release is safer and more effective than anterior release.

A total of 27 patients undergoing the staged posterior procedure were included in P–P group and 32 patients undergoing staged anterior/posterior procedure were included in A–P group. Halo-femoral traction was used after the release procedure for both the groups. The flexibility and correction rate were evaluated to quantify the contribution of spinal release and traction to curve flexibility. Radiographic outcomes were compared between the two groups before surgery, after release and traction, immediately postoperatively, and at the last follow-up.

Gender, release and fusion segments, duration and weight of traction, main curve magnitude, and curve type were similar between the two groups. Significant lower flexibility of main curve (p = 0.001) and higher global kyphosis (p < 0.001) was found in P–P group. For patients in the P–P group, the flexibility of major curve averaged 14.1% before surgery, which increased to 32.5% after posterior release and Halo-femoral traction (p < 0.001) and showed 44.9% correction postoperatively. Compared with patients in A–P group, patients in the P–P group seemed more benefited from release and Halo-femoral traction (18.4 vs.12.9%, p = 0.021) although they had significantly more rigid scoliosis before surgery (14.1 vs. 21.0%, p < 0.001). Besides, the final correction rate of the main curve was similar between the two groups (50.1 vs. 44.9%, p = 0.094). Five patients in the A–P group were found to have respiratory system related complications, whereas only one patient in P–P group experienced superficial pin site infection combined with deep venous thrombosis of the left limb.

Staged posterior surgery provides a safe and effective option for the treatment of severe rigid scoliosis. And posterior release seems superior for anterior release regarding the surgical outcomes.

PSOs are technically demanding given the proximity of neural structures and association with increased blood loss secondary to epidural and cancellous bleeding. Traditionally, straight osteotomes have been utilized to perform PSOs, which can result in a variable amount of correction achieved. This can lead to longer operative times and increased blood loss. We report a novel technique, where fixed-angled (25, 30, and 35 degrees) triangular shavers are utilized to perform the PSO resulting in more reproducible and time efficient osteotomies, which can ultimately lead to decreased blood loss.

A retrospective review of all patients who underwent an isolated single-level PSO, regardless of previous surgical history from August 2010 to January 2014 was performed. Patients were divided into two groups depending on the PSO technique utilized. Group 1 included all patients before August 2012, in which traditional straight osteotomes were utilized. Group 2 included patients where fixed-angled triangular shavers were used after their adoption in August 2012. Fusion levels, number of Smith–Peterson osteotomies (SPOs), number of revision surgeries, previous fusion mass and the need for osteoclasis and fusion takedown, total operative time, PSO associated operative time, total operative blood loss, PSO associated blood loss, utilization of blood products, ICU requirements, length of stay, major medical complications, and requirement for revision surgery were recorded.

There were 18 patients who had an isolated single-level PSOs performed during this time period. There were 8 patients in group 1, and there were 10 patients in group 2. No difference was found between the two groups in relation to mean age, height, weight, total operative time, total estimated blood loss, or number of levels fused. There was a difference in the number of osteoclasis and fusion takedowns among the revision patients. Group 1 included two patients who had fusion takedowns (two of six revisions, 33%), group 2 included eight patients (eight of eight revisions, 100%), (p = 0.018). Group 1 included 4 patients (four of eight, 50%) who underwent Smith–Peterson osteotomies (SPOs), whereas group 2 included 10 patients (10/10, 100%), (p = 0.008). Among all the patients with SPOs, there was no difference in the number of SPOs performed (mean = 4.5). There was a statistical difference in PSO associated blood loss and osteotomy time between the two groups. Mean PSO time for group 1 was 52 minutes, whereas group 2 was 33 minutes, (p = 0.032). Mean PSO associated blood loss for group 1 was 1,018 mL, whereas group 2 was 463 mL (p = 0.047). Group 2 had shorter ICU LOS (3 vs. 6 days, p = 0.030), as well as a shorter overall hospital LOS (6.1 vs. 9.3, p = 0.041). There was a statistical difference in major complications between groups 1 and 2. Group 1 had six patients with eight major complications, and group 2 had three patients with three major complications (p = 0.029).

We report our experience of a novel and highly reproducible ZSO technique to perform PSOs utilizing fixed-angled, triangular shavers, which decreased associated PSO times by 37%, PSO blood loss by 55%, LOS by 34%, and perioperative morbidity.

Management of the anterior compressive pathology of the craniovertebral junction (CVJ) is complex and demanding. We review our experience with the transoral surgical decompression of fixed anterior CVJ lesions, with particular attention to the decision making and to the indication for a consecutive stabilization.

Retrospective study (2000–2013) of 47 consecutive patients (14 males and 13 females). Mean age was 59.2 years (range, 32–82 years). Encountered lesions were rheumatoid arthritis with pannus (29, 9 of which with associated cranial settling), ankylosing spondylitis (four), tumors (seven: six extradural chordomas/chondrosarcomas and one metastasis), odontoid fractures with hypoporosis, and rotational instability (seven). Patients presented with a variety of following symptoms: high cervical pain (82%), varying degrees of quadriparesis (64%), lower cranial nerve deficits (23%), and central cord syndrome with neurogenic bladder (14%). All patients underwent one-stage transoral decompression and consecutive posterior atlantoaxial or occipitocervical stabilization. Clinical evaluation was made pre- and postoperatively using the Ranawat score. Follow-up period ranged between 6 and 48 months (average, 22 months).

According to the Ranawat score, we had 21 grade I patients, in 20 of which pain was eradicated, 10 grade II patients, 8 of which passed to grade I, 11 grade IIIA patients, of which 6 passed to grade I and 5 to grade II, and 5 grade IIIB patients of which 4 passed to grade IIIA. In seven patients, the transarticular screws crossed the anterior cortex of the atlas, without clinical manifestations. In five patients, complete reduction of the C1–C2 rotation was not possible, because of the chronic nature of the defect. Surgical morbidity occurred in five cases (three dural tears and two occipital wound infections). There were two perioperative deaths ([a] dural rupture, pneumoencephaly, meningitis, and massive pulmonary embolism, [b] pulmonary infection, and cardiorespiratory arrest).

Successful and stable decompression of the CVJ requires extensive preoperative evaluation, appropriate tailoring, and adequate expertise. The transarticular C1–C2 fixation is a safe and effective stabilization method when the atlanto-occipital joints remain competent. Complications appear mostly in patients with rotational deformity of the C1–C2 complex. Patients with clinical and radiological findings of myelopathy improve less even if surgery is successful.

Surgical treatment of severe and rigid spinal deformities is usually difficult and challenging to perform. The goal of surgical treatment is to obtain a satisfactory balance both in sagittal and coronal planes. In rigid deformities, the osteotomies are usually insufficient; vertebral column resection is the only option of treatment. To reduce the operation time and complications, a single stage, posterior vertebral column resection (PVCR) is defined by Suk et al. It enables rotational and translational correction of spinal column and provides an opportunity for manipulation of anterior and posterior column simultaneously. In the original PVCR, posterior elements of resection side were removed first and then the anterior part removed and correction was performed. The authors decided to make a modification in PVCR as performing the posterior total laminectomy, facetectomy, and pediclectomy after vertebral body resection. This method has two major advantages; minimization of the blood loss from epidural veins after laminectomy and protection of the neural elements from direct injury during vertebral body resection.

A total of 11 patients between the age of 3 and 63 years, diagnosed with severe spinal deformity with limited flexibility, who underwent modified PVCR were reviewed. The average follow-up was 2 years (range, 5 months–3 years). There were six female and five male patients with a mean age of 18 years. Severe congenital scoliosis was found in seven patients, congenital kyphosis in two patients, neurofibromatosis in one patient, and posttraumatic kyphosis in one patient. The surgery consisted of temporary fixation of vertebral column, resection of vertebral body first then resection of posterior elements, followed by deformity correction and fusion.

The mean estimated blood loss was 1,072 mL (range, 350–2,000 mL). Overall, 39.45% (range, 33–50%) of total blood loss occurred after vertebral body resection, 60.91% (range, 50–67%) occurred after posterior elements removal. The ratio of estimated blood loss to estimated body blood volume was 26% (range, 19–52%). The deformity correction was 60% in the coronal plane. No neurological complications were encountered.

The PVCR is a complicated, technically demanding procedure with possible risks for major complications. All correction attempts must be performed under direct inspection, palpation of tension in the spinal cord by a highly experienced surgeon. Spinal cord neuromonitoring is a must to prevent neurological injuries. The authors modified the original technique defined by Suk and performed by various surgeons. The authors believe that making vertebral body resection before laminectomy would decrease the blood loss and protect the spinal cord. The validity of this new modified technique should be demonstrated in a prospective, randomized, controlled study with a larger patient population allowing comparison of age-matched subgroups.

Surgical manipulations at C7 level present the most difficulty during a posterior cervicothoracic fusion where instrumentation across the cervicothoracic junction is required. There is increased risk of vascular injury, neurological injury, and possibility of postoperative instability because of the surgical complications at this site. Placement of C7 instrumentation also poses additional difficulty during rod placement. Vertebral artery (when present) and C8 nerve roots are the most important structures susceptible to the surgical injury at C7 level. Our clinical observations suggested that skipping instrumentation at C7 in a multiple level posterior cervicothoracic fusion will result in minimal intraoperative complications, decreased surgical time, while still maintaining fixation, sagittal balance parameters, and successful rates of fusion.

This was a retrospective chart review of 49 patients (mean age: 62 years; range: 45–87 years) undergoing multilevel posterior cervicothoracic fusion between November 2010 and October 2014. Of the 49 patients, 42 had no screws placed at C7 level and 7 patients had instrumentation done at C7 and served as a control group. Assessment of the safety and efficacy of skipping C7 instrumentation were based on intraoperative complications, operative time, estimated blood loss (EBL), and radiographic evidence of fusion and spine stability.

There were no intraoperative complications though two patients (one skipped and one not skipped) required extended time under anesthesia because of the difficulty in patient positioning and intubation. Skipping C7 resulted in reduced average operative time compared with those patients instrumented at C7 (203 vs. 171 minutes, respectively). In addition, skipping C7 reduced average EBL compared with patients instrumented at C7 (531 vs. 445 mL, respectively). In addition, patients skipped at C7 maintained sagittal balance with fusion rates identical to control patients at follow-up with a very low incidence of pseudarthrosis.

Skipping instrumentation at C7 in a multilevel posterior cervicothoracic fusion demonstrates lower EBL and faster operative times compared with performing instrumentation at the C7 level. In addition, in a postoperative assessment of patients undergoing posterior cervicothoracic fusion identical rates of fusion were achieved. Serious negative outcomes of skipping C7 were not found in this retrospective study. The results of this study point to the clinical benefits of skipping C7 to minimize surgical risk and complications in patients undergoing posterior cervical fusion across the cervicothoracic junction.

Incidence of deep surgical site infection (SSI) in spinal fusion varies from 0.3 to 20% according to the international literature. Instrumentation is a well-established risk factor for this complication. Higher morbidity and mortality rates and increased cost of treatment up to fourfold are associated with this complication. Prophylaxis with intravenous antibiotic is consensual, but few studies have evaluated the efficacy of topical agents in the surgical site with prophylactic intent. Irrigation with 3.5% povidone iodine and application of lyophilized vancomycin powder in surgical site have shown benefit, but there are no studies comparing these two methods. A comparative study using topic povidone iodine and vancomycin powder was conducted to reduce this knowledge gap.

The medical records of 439 patients who underwent spinal fusion with instrumentation for traumatic spinal lesion treatment were analyzed. Procedures were consecutively performed at Joao XXIII Hospital (level 1 trauma center). Patients were combined in the following two groups, according to the prophylactic agent used: Povidone iodine (PVPI) historical series (n = 181), performed from January 2009 to April 2012 and vancomycin (VANCO) cohort study (n = 239) conducted from May 2012 to December 2013. The surgical site in PVPI group was irrigated with 5% topic iodine solution during 3 minutes, before deep lumbar fascia closure. One gram of vancomycin powder was applied directly to the hardware in VANCO group. Both the groups received 2 g of intravenous cefazolin 30 minutes before surgery and had surgical site exhaustively washed with saline 0.9%, before closure in PVPI group and prior to apply vancomycin powder in VANCO group.

No difference according to mean age, sex, and lesion level distribution (cervical × thoracolumbar) was observed between the two groups. Number of levels instrumented, coexisting infection, and surgical access were not compared because of a lack of information in medical records, especially those from PVPI series. SSI rate was lower in VANCO group (1.67%) compared with PVPI group (6.62%), this difference was statistically significant (chi-square test with Yates correction = 5.618; p = 0.018; IC 0.069–0.824).

The application of 1 g vancomycin powder in surgical site was superior to irrigation with 5% povidone iodine in the prophylaxis of deep surgical site infection. These results are valid for patients with spinal trauma who underwent instrumented fusion. Variability in surgical team, difference in the interval admission surgery (patients recently are being operated earlier), and number of levels instrumented are possible bias to this study. The low cost and easy applicability of topic prophylactic measures justify new studies with better statistical power (multicenter and randomized).

This study aims to evaluate the reliability of three-dimensional (3D) volume rendering computed tomography (CT) in postoperative assessment of pedicle screw placement.

A total of 98 patients with previous spinal fixation surgery were included. All inserted screws were evaluated postoperatively within the first week using CT. Degree of misplacement and difference between CT images were recorded.

Overall, 76, 68, and 39 misplaced screws were detected in 3D reformatted image, coronal reconstruction, and axial CT images, respectively. Dorsal spine had higher rate of violation 46 (9.95%) with the highest rate at T4 (12.8%) comparing it with lumber 32 (6.9%). Statistically significant differences were found between lateral and medial violation (p = 0.03), between findings of CT 3D reformatted and axial image (p = 0.04), and also in detecting end plate perforation and anterior vertebral encroachment in different CT images (p = 0.013). Sensitivity for 3D reformatted image and axial image compared with surgical finding in six revised screws was 100 and 95.8% and specificity 100 and 88.7%, respectively. Highly momentous agreement reported with Kappa coefficient = 0.95 Â ± < 0.001.

The vertebral body and the pedicle are 3D structures. Therefore, we have to study them as they are. The postoperative evaluation of pedicle screw using CT 3D reconstruction was a reliable method and unveiled the deficiencies in conventional axial CT.

Injury to the spinal cord and the spinal column is relatively uncommon in pediatric population. It accounts for roughly 5% of the total spinal cord injuries. SCI in children younger 5 years are even rarer. Objective of the study was to analyze the incidence, type of spinal injuries, and epidemiological parameters in Indian children with spinal injury admitted at Indian Spinal Injury Centre (ISIC).

Hospital medical records were reviewed and patients with the diagnosis of cervical spine injury in age group 0 to 18 years admitted between 2002 and 2011 were included. The injury characteristics of patients were compared across three groups of 0 to 9, 10 to 14 and 15 to 18 years of age.

A total of 152 spinal injury patients were included in this study, which represents 10% of the total pediatric trauma admitted at our hospital. Boys (78%) were more commonly injured than girls. Fall (51%) was the most common mode of injury followed by motor vehicle accident. Cervical spine was the most common level of injury with 34% of cases followed by thoracic region with 30% of cases. However, the proportion of both genders, mode of injury, and levels of injury were not different across the age groups (p < 0.05). Fracture was the most common pattern of injury in all age groups. SCIWORA was not very common (6.6%) in our study. Patients were divided according to ASIA scale in to complete and incomplete category. Outcome was measured on the basis of improvement in patient neurological level and their dependency level.

This retrospective study in Indian children is comparable with other international studies and provides important information regarding patient and injury characteristics of pediatric trauma cases.

As war injury patterns have changed throughout Operations Iraqi and Enduring Freedom (OIF/OEF), a relative increase in the incidence of complex lumbosacral dissociation (LSD) injuries has been noted. LSD injuries are an anatomic separation of the spinal column from the pelvis, and represent a manifestation of severe, high energy trauma. We assessed the clinical outcomes of combat-related LSD injuries after operative treatment.

We performed a retrospective review of all patients surgically managed for complex LSD injuries since the beginning of current combat operations in the Middle East.

A total of 20 patients met inclusion criteria and were treated as follows: posterior spinal fusion (12), sacroiliac screw fixation (7), and combined anterior–posterior fusion (1). The mean age was 28.2 years. The most common mechanism of injury was mounted improvised explosive device (IED, 50%). On average, 2.2 spinal regions were injured per patient. Neurologic dysfunction was present in four patients. Three patients underwent operative stabilization of their injuries before evacuation to the United States. Median time to surgery from injury was 12 days (range, 0–111 days). There was a 20% wound infection rate. Median follow-up was 45.5 months (range, 23.2–105.3 months), and one-third of all patients were medically retired because of their injuries. At most recent follow-up, 45% complained of chronic low back pain and 35% had persistent neurologic deficits; however, 30% were actively engaged in strenuous physical activities, including swimming, distance running, and training for special forces.

This is the largest series of operatively managed lumbosacral dissociation patients currently reported. Our series suggests that combat-related lumbosacral dissociation injuries frequently result in persistent, long-term neurologic dysfunction, disability, and chronic pain. Operative management carries a high postoperative risk of infection. However, two-thirds of patients were able to remain on active duty after their injuries, and two patients were able to complete marathon training.

Spine surgery is a growing and challenging subspecialty in most health systems in Latin America and Peru, where the extent of its possibilities must attend an overflowing spine pathologies demand, such as traumatic and degenerative; considering that budgetary resources with almost immediate availability and trained medical specialists are imperative needed. Continuing medical education and subspecialization with competency-based curricula responds to the rapid expansion of technology and knowledge in this field, a fact which promotes better patient care, a greater sense of responsibility and dedication, a trend of critical analysis and research, and certainly the possibility to get more attractive job opportunities. This study examines the gaps in knowledge of the author who developed a 3 months' Postdoctoral Training AOSpine Fellowship Program, focused on traumatic and degenerative spine pathology, at the Department of Spine Diseases of the Instituto de Ortopedia e Traumatologia (IOT) FMUSP, Sao Paulo, Brazil.

AOSpine Fellow Neurosurgeon activities in the scope of spine diseases were evaluated over a first period of 6 months before training (n = 12 patients) and a second period of 6 months after training (n = 18 patients) at the Neurosurgical Unit, Department of Surgical Specialties of the Hospital Antonio Lorena del Cusco, Peru; with emphasis in the fields of clinical and surgical practice (clinical, radiographic, and operative records from the whole 30 consecutive operative patients group with traumatic and degenerative diseases), academic performance, and research tasks. Multivariable linear regression was used to evaluate the relationship between experience level of the surgeon and surgical performance; as well as mentioning differences in the other two practice fields.

Real differences between two periods were identified with the greatest difference in better performance seen on completing the fellowship (vs. nonfellowship): cervical trauma (80 vs. 62%), cervical stabilization (71 vs. 54%), thoracolumbar trauma (92 vs. 59%). and degenerative spine diseases (65 vs. 47%) and its complications (36 vs. 31%). In the second period, surgical correction and level of complications were significantly better; meanwhile, operative time and length of patients stay were significantly longer. No group differences were founded with respect to estimated blood loose (EBL), transfusion rates, and postoperative infections. Other advantages of the posttraining period were review log cases, surgical technique discussion, analysis of biomechanics, classification system, surgical approach and planning, number of screws placed, and stronger constructs. Finally, two spinal research projects were developed in the posttraining surgery.

To provide an efficient and safe service covering the broad spectrum of spinal pathology, a formal AOSpine fellowship, ideally with a formal curriculum, should be considered and recommended. Advantages include optimization of the diagnostic process, therapeutic classification, biomechanical analysis, neuroimaging study, selection of material, and user satisfaction. Research activities and academic industry support must be enhanced.

Osteoporotic vertebral compression fractures (VCFs) are a significant cause of disability because of the pain in the elderly population. Kyphoplasty has been advocated as a treatment alternative for the successful management of these fractures in terms of immediate pain relief, and also for restoration of the premorbid level of daily activities. In this retrospective study, the authors report their experience in the period of 8 years (2007–2014) with the early and late management of VCFs with kyphoplasty using a unilateral pedicular approach.

A retrospective analysis was conducted in 80 patients (59 women and 21 men) whose ages ranged from 55 to 92 years (mean age, 73 years). The interval between onset of symptoms and surgical intervention ranged from 3 to 12 weeks. Overall, 90 levels (67 thoracic and 23 lumbar) were treated using the unilateral pedicular approach in this cohort. Immediate and early postoperative (3-month follow-up visit) visual analog scale (VAS) pain scores, activity levels, and restoration of vertebral body (VB) height were assessed.

The mean preoperative VAS score was 8.4, whereas the immediate and early postoperative scores were 1.7. These findings reflected a resolution of 85 to 100% of preoperative pain. All patients resumed routine activities within hours of the procedure, although improvement in VB height was not accomplished in this cohort. No major complications were encountered in this clinical series.

Kyphoplasty using a unilateral pedicular approach in this cohort proved to be an effective method for the treatment of osteoporotic VCFs, although failure to restore VB height does not seem to interfere with the excellent pain management and good functional outcome provided by this procedure.

Cervical sagittal alignment (C2–C7 SVA) has been correlated to myelopathy severity but kyphosis as a regional parameter has not been demonstrated to correlate with health-related quality of life (HRQOL) measures. We hypothesized that regional and focal sagittal cervical alignment may also correlate with HRQOLs in patients with cervical spondylotic myelopathy (CSM).

Post hoc analysis of a prospective, multicenter database of patients with CSM. A total of 151 patients met inclusion criteria (47%): symptomatic CSM, age > 18 years, baseline lateral radiographs, modified Japanese Orthopaedic Association (mJOA) and neck disability index (NDI). Average age was 56.3 ± 11.7 years with females making up 43.9% (n = 69) of the study population. Regional alignment and HRQOLs were analyzed with patients stratified into a high-cSVA group (hiSVA, n = 45, 0.5 SD ≥ mean) or a low cSVA group (loSVA, n = 43, 0.5 SD ≤ mean). Focal alignment (kyphosis and olisthesis between adjacent vertebrae) analysis was also conducted.

The hiSVA (mean cSVA 39.4 ± 7.4 mm) cohort had a significantly worse mJOA than the loSVA (mean cSVA 11.31 ± 5.3 mm) cohort (mean mJOA 12.5 vs. 13.7, p = 0.037). No significant correlations between C2–C7 lordosis and HRQOLs existed. There were significant correlations with focal alignment and worse clinical assessments: max sagittal slip with mJOA (R = −0.24, p = 0.002) and Nurick (R = 0.18, p = 0.024). Level of slip was also significant, with olisthesis at higher levels correlating with worse health status. Number of kyphotic segments also positively correlated with NDI (R = 0.19, p < 0.001).

Similar to previous studies, high baseline cSVA correlated with significantly worse mJOA. Interestingly, the mean cSVA of the hiSVA cohort was 39.4 ± 7.4 mm, suggesting that 40 mm may be a potential threshold below which cervical sagittal malalignment should be corrected. Regarding focal alignment, increased olisthesis is correlated with worse mJOA and Nurick grade, especially at higher cervical levels. Even focal abnormalities all along the cervical spine are correlated with worse NDI, demonstrating that while level of olisthesis may matter, the number of vertebrae with a kyphotic relationship may also cause pain and disability.

Occipitocervical instability with vertical odontoid migration is a rare but potentially debilitating anomaly. Anterior decompression followed by posterior stabilization is commonly used to address the pathology, but the former is associated with significant morbidity. More recently, posterior-only techniques have been described to obtain reduction and stabilization for nonfused cases of cranial settling.

Retrospective analysis of seven cases of patients (four males, three females, age range 34–73 years) who suffered from occipitocervical instability with reducible vertical dislocation of the odontoid in the setting of various underlying pathology. Six patients were myelopathic preoperatively. The neurological status was classified according to the Nurick scale. Pain was assessed according to the Visual Analog Scale. Radiological measurements included preoperative and postoperative evaluation of the position of the tip of the odontoid process in relation to Chamberlain, McGregor, McRae, and Wackenheim lines, and measurement of the Ranawat line, the clival angle, and the Klaus height index. Follow-up ranged from 8 to 42 months.

Five patients improved neurologically, and one remained stable. Pain improved significantly in these patients, and was completely eliminated in three of them. Obvious reduction of the deformity was demonstrated by the postoperative radiological craniometric measurements. One patient did not improve neurologically. Postoperative imaging revealed a very small reduction with practically unchanged ventral compression of the cord. He underwent transoral decompression at a second stage. No patient suffered from severe complications. No screw pullout, loosening, or fracture of implant has been observed so far.

Modern screw–rod systems enable intraoperative correction of nonfused deformity and indirect decompression of the cervicomedullary junction obviating the need for ventral decompression or preoperative traction. Patient selection is critical to ensure successful application of the reduction maneuvers.

In general, deltoid palsy develops in patients with cervical disc herniation (CDH) at the level of C4–5, resulting in compression of the C5 nerve root. Because of duplicate nerve innervation, however, deltoid palsy can also develop when CDH is at the levels of C3–4 and C5–6. To date, little has been known about the surgical outcomes of CDH causing deltoid palsy. We report on by far the largest series of CDH causing deltoid palsy focusing on surgical outcomes in the literature.

A total of 61 patients with CDH causing deltoid palsy (less than grade 3) were identified among 13 surgeons and included in this study. Average age of the patients was 51.4 years (range, 25–69 years), with 49 males and 12 females. Overall, 35 patients were soft disc and 26 patients were hard disc. Overall, 32 patients had single-level CDH (22 C4–5, 9 C5–6 and 1 C3–4), 22 had two-level (19 C4–5-6, 2 C3–4-5 and 1 C5–6-7), 4 had three-level (4 C4–5-6–7), 3 had four-level (3 C3–4-5–6-7). All the patients underwent surgery for deltoid palsy and arm pain not responding to conservative treatment: 57 ACDF, 2 ADR, and 2 foraminotomy and discectomy. Average follow-up was 20.7 months (range, 6–83 months). The severity of deltoid palsy was classified into five grades according to manual motor power test, and the severity of radiculopathy was recorded on a visual analog scale (VAS) of arm pain (0–10 points). The degree of improvement in both the severity of deltoid palsy and arm pain following surgery was evaluated. Patients with accompanying myelopathy, shoulder diseases, or peripheral neuropathy were excluded from the study.

Average duration of deltoid palsy was 11.9 weeks (range, 1–156 weeks). Both deltoid palsy and radiculopathy improved significantly with surgery (2.4 vs. 4.5 grades, p < 0.001) and (6.4 vs. 2.1 points, p < 0.001), respectively. Of 61 patients, 36 (59%) patients achieved full recovery of deltoid palsy with an average time of 8.4 weeks (range, 1–54 weeks). Longer duration of deltoid palsy negatively affected the degree of improvement of deltoid palsy after surgery (correlation coefficient −0.351; p < 0.01). Severity of preoperative deltoid palsy, type of disc (soft disc or hard disc), and gender did not affect the degree of improvement of deltoid palsy after surgery.

This study demonstrates that surgical decompression significantly improves the degree of deltoid palsy and radiculopathy because of the CDH irrespective of the type of disc. The longer the duration of deltoid palsy preoperatively, the lower the degree of improvement of deltoid palsy postoperatively. Thus, early surgical decompression is recommended for improvement of deltoid palsy in patients with CDH.

Cervical stenosis is a defining feature of CSM. Matsunaga et al proposed that elements of stenosis are both static and dynamic, where the dynamic elements magnify the canal deformation of the static state. We hypothesize that dynamic motion may be associated with myelopathy severity and neck disability and present novel methods of dynamic motion analysis in CSM.

Post hoc analysis of a prospective, multicenter database of patients with CSM. A total of 110 patients (34%) met inclusion criteria symptomatic CSM, age over 18 years, baseline flexion/extension radiographs, and HRQOLs (mJOA, NDI, SF-36, and Nurick grade). The mean age was 57 ± 12 years with 41% female (n = 46). Correlations with HRQOLs were analyzed for regional and focal parameters in flexion and extension. Baseline dynamic parameters (F/E cone relative to a fixed C7, center of rotation, range of motion arc relative to the COR) were also analyzed for correlations to HRQOLs.

At baseline, the mean HRQOLs demonstrated disability and the mean radiographic parameters demonstrated sagittal malalignment. Among regional parameters, there was a significant correlation between increased C2–C7 angle in flexion and Nurick grade (R = 0.189, p = 0.048) with no significant correlations in extension. Focal parameters including C7 slip were significantly correlated with disability (Flex R = −0.377, p = 0.003; Ext R = −0.261, p = 0.027). Reduced flexion/extension motion cones, a more posterior center of rotation, and smaller range of motion correlated with worse HRQOLs.

Dynamic motion analysis may play an important role in understanding CSM. Focal parameters demonstrated a significant correlation with worse HRQOLs especially C7 slip in flexion and extension. Novel methods of motion analysis demonstrated reduced motion cones correlated with worse myelopathy grades. More posterior center of rotation and smaller range of motion were both correlated with worse general health scores (PCS and Nurick).

Perform a retrospective review of a single site experience with the STALIF-C (Centinel Spine) integrated cervical fusion device and OsteoCel + stem cell–derived allograft material (NuVasive, Inc.).

We reviewed all charts of patients undergoing an anterior cervical discectomy and fusion (ACDF one, two, and three levels), utilizing the STALIF-C device and Osteocel + bone graft material. Data comprised patients from January 2012 to April 2014, with an average final imaging follow-up of 5 months. All patients underwent the ACDF by the same surgeon at the same institution. Fusion criteria were assessed primarily by thin cut CT scans with multimodal reconstructions, but also with dynamic X-rays if CT imaging was unavailable. We implemented a standardized CT fusion criteria, for which all images were read by an independent Board Certified Neuroradiologist. Criteria for fusion was based on a grade 1 to 5 scale (CT imaging), and/or no movement on dynamic X-rays of greater than 2 degrees.

A total of 101 patients were included in the study, with imaging and clinical follow-up obtained in 101 patients (100%). There were 39 males and 62 females, with an average age of 54. The break down in the number of levels treated was as follows: One level (49%), two levels (36%), and three levels (15%). Overall, 14% of the patients were active smokers, 11% had a history of former nicotine abuse, and 74% were nonsmokers. All the follow-up fusion assessments were done with thin cut CT scans with sagittal and coronal reconstructions, and dynamic X-rays. The fusion rates for the levels treated were as follows: one level (98%), two levels (94%), and three levels (87%). The integrated fusion rate was 95% without separating the procedures by levels. There were no incidents of hardware failure or break, with only one patient requiring a posterior cervical fusion for symptomatic pseudoarthrosis (multilevel fusion patient).

The STALIF-C integrated cervical fusion device, in conjunction with Osteocel + stem cell–derived bone graft material is a safe, effective, and reproducible fusion construct in the treatment of cervical degenerative disc disease. The rates of fusion, as compared with systematic meta-analyses in the literature, are comparable and in some cases superior to reported rates using standard cervical plating and cage constructs. To the best of our knowledge, this is the largest review analysis of any integrated cervical fusion device.

Anterior cervical discectomy and fusion (ACDF) has become a standard surgical option for patients with neck pain or radicular symptoms who failed nonoperative care. Although outcomes are generally good in patients undergoing single-level procedures, results for two-level cases have been less consistent. The purpose of this study was to compare results of single level. ACDF with those of two-level ACDF in patients serving as control groups in a total disc replacement trial.

This was a post hoc analysis of data from two control arms of the Food and Drug Administration regulated trial for the Mobi-C artificial disc. As the control treatment, ACDF with allograft and anterior plate was performed at one level in 81 patients and at two levels in 105 patients for the treatment of symptomatic disc degeneration. The study selection criteria, surgical technique, and outcome measures were identical with the only exception being pathology and surgery at one or two levels. Radiographic assessments were performed by an independent laboratory. In the two-level group, both the levels had to be radiographically fused for the patient to be considered fused.

Gender, age, body mass index, and 5-year follow-up rates (∼ 75%) were similar in the two groups. Operative time and blood loss were significantly less in the single-level cases (p < 0.05). Preoperative Neck Disability Index (NDI) scores were similar in the two groups and both improved significantly by 6 weeks and remained significantly improved through follow-up (p < 0.05). The scores improved by approximately 50% in both the groups. Scores in the single-level group were significantly less at several time points. Visual analog scale scores assessing neck and arm pain followed a pattern similar to NDI, with significant improvement in both groups at 6 weeks' postoperative being maintained through 5 years, with few significant differences between groups. Both groups had significant improvements in SF-12 PCS and MCS scores by 6 months which were maintained throughout follow-up. The single-level group had significantly greater PCS scores at 12-month follow-up and thereafter (p < 0.05). There were no significant differences in MCS scores between the groups. At 5 years, there was no significant difference in index level secondary surgery rates (11.1 vs. 16.2%). At 60 months, the one-level group fusion rate was 93.3versus 86.1% in the two-level group (not statistically significant). Fusion rates were significantly greater in the one-level group at 6 and 12 months. There was a trend (not statistically significant) for greater adjacent segment degeneration at the inferior segment in the two-level group.

The design of the disc replacement study created a unique opportunity to compare one- versus two-level ACDF control groups, which used the same inclusion/exclusion criteria and evaluations. Single-level ACDF outcomes were better on a few measures. However, patients in both groups had significantly improved scores on various outcome measures early after surgery and these improvements were maintained throughout 5-year follow-up.

To assess the safety of Zero Profile Interbody fusion (Zero P) device in anterior cervical decompression and fusion (ACDF) for degenerative cervical stenosis.

Patients and Method: A total of 89 consecutive patients treated with Zero P interbody device from September 2009 to September 2012 were included in this retrospective study. Inclusion criterion: Degenerative cervical stenosis with myelopathy, persistent radiculopathy after at least 3 months of failed conservative management. Exclusion criterion: Pediatric population; patients with infection, metastatic disease, and trauma. There were 39 females, 50 males with mean age of 55 years (ranging from 24 to 84 years). Overall, 56 (64%) had surgery at one level, 31 (35%) at two levels, 1 (1%) at three levels. Total number of levels operated were 121. Common levels operated were C56 (62%) and C67 (47%). Majority were operated because of the radicular symptoms, 56 (64%) had radicular symptoms, 28(31%) had myelopathy, and 5 (5%) myeloradiculopathy.

All had a minimum of 6 months' follow-up (maximum 2 years). No patient had cage subsidence or extrusion. Overall, 1 patient had superficial infection which settled with antibiotics, 10 (11%) had dysphagia which settled in 6 to 12 weeks

Our study demonstrates that ACDF with Zero P can be considered a safe option in management of the patients with cervical degenerative stenosis. We would also recommend a prospective randomized study as a follow-up on to this retrospective study. Preoperative kyphosis or lordosis did not change the outcome or make the surgical technique any more difficult, hence, this implant can also be used in these circumstances.

The surgical management of cervical brachialgia utilizing anterior cervical discectomy (ACD) and posterior cervical foraminotomy (PCF) is a controversial area of spine surgery. Few studies have compared the effectiveness of both interventions. These studies were however flawed by utilization of nonvalidated outcome measures, nonstatistical analysis, and importantly lack of preoperative analysis to ensure both groups were matched. Taking this into account, the authors aimed to compare the effectiveness of both surgical interventions using validated outcome measures. It will be the first study in the literature to be doing this.

The authors conducted a 5-year retrospective review (2008–2013) of outcome following both the above surgeries and also compared the effectiveness of both techniques. Patients with previous neck surgery, myelopathy, and large central discs were excluded. The main outcome variables measured were Neck Disability Index (NDI), Visual analogue scores (VAS) for neck and arm pain. Wilcoxon signed rank test and student t test were used to test differences.

A total of 150 ACDs and 51 PCFs were performed for brachialgia. Overall, 26 (17.3%) and 13 (25.5%) patients with ACD and PCF were lost to follow-up, respectively. Median follow-up for the ACD and PCF group were 5 months (range, 1–45 months) and 1 month (range, 1–30 months), respectively. There were no differences in the preoperative NDI, VAS neck, and arm scores between the groups (p > 0.05). As expected, both ACD and PCF delivered statistically significant improvement in NDI and VAS neck and arm scores. The degree of improvement of NDI, VAS neck, and VAS arm were similar between both the groups of patients (p > 0.05) with a trend favoring the PCF group. The amount of blood loss and length of operation were comparable between both the groups (p > 0.05). There was a nonsignificant trend that ACD was effective in compression related to disc and PCF being more effective in foraminal pathology. In the ACD group, two (1.3%) patients needed repeat ACD due adjacent segment disease. One (0.7%) needed further decompression via PCF. Four (2.7%) and seven (4.7%) patients with ACD had hoarse voice and dysphagia respectively all of which improved on follow-up. In the PCF group, one (2.0%) patient needed ACD because of the persistent brachialgia.

Our study shows that PCF is an alternative to ACD for treating patients with brachialgia with both modalities being equally effective. There were no differences in postoperative neck pain nor need for further surgery between the two procedures however the risks of hoarse voice, dysphagia, and adjacent segment disease could be avoided with PCF. This is the first study to utilize validated outcome measures to prove the effectiveness of PCF and that it is comparable to ACD. This is a medium-sized, single center, unrandomized, and retrospective study. Nevertheless, it is the authors' belief that this study, interpreted in association with previously published studies, provides strong justification for conducting a large multicenter, randomized controlled trial comparing these two treatment options. The authors are currently setting up a prospective clinical trial to help address this question further.

It is generally accepted that laminoplasty is a safe and reliable surgical treatment for cervical spine myelopathy (CSM) because of the spinal canal stenosis. There are multiple techniques of laminoplasty for spinal cord decompression and most of them require expensive instruments or spacers to stabilize the lamina. In the Hospital for Traumatology and Orthopaedics at Ho Chi Minh city, Vietnam, we performed the Z-plasty operation (Sakou technique) since 2004 to present for patients with CSM with an effort to reduce the cost of treatment.

It is a retrospective study. Patients suffered from CSM treated by Z-plasty technique are selected. We performed the Sakou technique, which open one lamina to the left, then the next lamina to the right and the next one to the left, consecutively and respectively. To keep the lamina opened, we tight them in pairs with unabsorbable sutures. Patients were instructed to wear hard collar for 1 week, and then started to follow our rehabilitation program. We use JOA score system and recovery ratio of Hirabayashi to evaluate the neurologic outcome. For functional outcome of cervical spine evaluation, we use the Neck Disability Index (NDI).

There were 36 patients with a mean follow-up of 5 years (range, 1–10 years), sex ratio approximately 3:1, and a mean age of 61 years. The mean operating time and blood loss per lamina were 40 minutes and 55 mL, respectively. The final canal expanding ratio was 25%. For surgical complications, there were only three cases of C5 palsy with full recovery after 1 year. There was no case of dura tear or infection. The mean pre- and postoperative JOA score were 11.1 and 14.7, respectively. The recovery ratio was 68%, with 71% of cases considered as good and excellent. For clinical outcome, the mean NDI was 0.18 with 88% of cases considered as good and excellent. The mean preoperative and final lordotic angle of cervical spine were 21.1 and 19.3 degrees, respectively, with no statistical significance.

The Z-plasty is a safe and reliable technique with a good outcome on neurological, anatomical, and clinical aspect which can be compared with other techniques. The absence of foreign bodies such as titanium plates or spacers reduces considerably the risk of infection and the cost of treatment. Considering the risk–benefit and cost–benefit ratio, this operation is particularly suitable for low-income patients in the developing countries.

Autograft bone as a fusion substrate is still the gold standard in the procedure. However, few studies have reported that using autologous cervical laminae as the bone graft in ACDF during the combined posteroanterior cervical spine surgery.

This study aims to evaluate the feasibility of using autologous cervical laminae as the bone graft in ACDF and to describe the clinical and radiographic outcomes in patients undergoing combined posteroanterior cervical surgery using autologous laminae as bone graft in ACDF.

Computed tomography (CT) scan of the cervical spine were performed in 50 adult cases. The heights of the laminae and the middle intervertebral space from C3 to C7 were measured on the CT planes. Then, 16 patients (nine males and seven females) with cervical spondylotic myelopathy underwent one-level combined posteroanterior procedure with anterior plate fixation from January 2010 to January 2013. Patients underwent combined posteroanterior surgery with laminectomy and ACDF. The structural laminae obtained from laminectomy were used as bone graft in ACDF. The clinical and radiographic outcomes of the patients were analyzed and the effectiveness and safety of the surgery was evaluated.

The average height of the laminae and the middle intervertebral space from C3 to C7 were 11.18 ± 1.05 mm and the 5.75 ± 0.58 mm, respectively. Statistical significant difference was found between the heights of the laminae and the space (p < 0.001). All the patients were followed up and the average follow-up period was 25.5 ± 3.1 months. All patients had immediate postoperative resolution of symptoms and radiographic evidence of solid fusion 3 months later. Postoperatively, excellent results were reported in 62.5%, good results in 18.8%, and fair results in 18.8% of the patients according to Odom criteria. Visual analog scale score of the neck and extremities pain was significantly decreased after the surgery (p = 0.014). The average preoperative and postoperative lordosis angles of the cervical spine were 24.42 ± 13.84 degrees and 32.91 ± 7.79 degrees, and the difference was significant (p < 0.01). Little loss of the angle was noted at final follow-up (32.91 ± 7.79 vs. 29.30 ± 7.88 degrees, p = 0.51). Anterior intervertebral space height was significantly increased (p < 0.001) after the surgery and a little declined at final follow-up (p = 0.43). No intraoperative complication was noted in the patients and three patients got self-limiting dysphagia postoperatively, who recovered spontaneously.

The height of the cervical laminae is adequate for bone graft in ACDF. Structural autograft harvested from the laminae provides a viable alternative to AIC grafting.

Our clinical study design was prospective, concurrently enrolled, and single-center trial of the combination of fusion (intervertebral cage with or without ventrofixation) and cervical disc prosthesis implantation in the treatment of patients with multiple level degenerative disc disease. The cervical disc arthroplasty become more and more popular in the surgical treatment of the degenerative cervical disc disease. The goals of the cervical disc arthroplasty are to maintain or restore intervertebral height, spinal balance and mobility, and to avoid adjacent segment degeneration. However, in most of the patients with multisegmental degenerative disc disease, the certain segments show different stage of degeneration and instability. The study was designed to investigate the clinical effects of the combination of cervical fusion and arthroplasty and to observe the stability, range of motion, and the cervical spine sagittal balance in the follow-up period.

Since December 2007 to September 2012, 36 patients with symptomatic cervical radiculopathy and/or myelopathy underwent surgery with this combined method. In 14 cases, the surgery involved two level, in 16 cases was three level, and 6 cases was four level. At the follow-up period, the patients' pain, neurologic function, and the radiographic parameters (range of motion at the level of prosthesis and the adjacent segments, the intervertebral disc height of the adjacent segments, lordosis of the whole cervical spine, and heterotopic ossification) were evaluated.

Early clinical experiences are promising. The segment of the prosthesis ultimately showed preservation of motion when compared with preoperative levels. The pre-op average ROM was 8.2 degrees (flexion/extension), the post-op average ROM 7.6 degrees. The whole cervical spine lordosis was pre-op 1.7 degrees the post-op 16.2 degrees. We have no implant-related failure.

The most important potential advantages of this method is that we can treat the multisegmental degeneration in each segment with the proper method including motion preservation and fusion, and restore the sagittal balance of the cervical spine. Although early results are promising, long-term follow-up studies required to prove its efficacy in the surgical treatment of the multisegmental degenerative cases.

Anterior cervical fusion (ACF) with anterior plating is generally considered the surgical standard of care for treating of cervical disc disease. Striving to improve or maintain outcomes while reducing complication risks led to “stand-alone” ACF implants with integrated cage and screw systems eliminating the use of traditional plates. Although a variety of such devices have been introduced, there is little published information available on their outcomes. The purpose of this study was to evaluate the results from stand-alone ACF and to compare results with existing data for ACF using allograft and an anterior cervical plate.

Data were collected for all patients who were a minimum of 12 months postoperative following stand-alone ACF at 1 or 2 levels, and who had no previous ACF (n = 59). Data collected included demographics, blood loss, visual analog scales (VAS) assessing neck and arm pain, neck disability index (NDI), and reoperations. Mailings and telephone calls were made to patients not recently seen in clinic to collect outcome data. To put the stand-alone ACF results into context, results were compared with a group of patients who served as controls in randomized studies comparing total disc replacement to ACF performed using allograft and an anterior plate (n = 57). The mean follow-up in both groups was approximately 22 months. The mean age in the stand-alone group was greater than in the allograft/plate group (50.7 vs. 42.4 years; p < 0.05) as was the percentage of patients undergoing two-level fusion (33.9% vs. 17.5%; p < 0.05).

Both the groups had statistically significant improvement in mean neck and arm pain VAS scores (p < 0.01, Fig. 1) with no differences between the groups (p > 0.05). In both groups, mean NDI scores improved significantly (p < 0.01). Regression analysis was performed to compare the percent change in NDI scores in the two groups to adjust for the preoperative NDI score being greater in the allograft/plate group and the differences in age and number of levels operated. The regression results found no significant difference but a trend favoring allograft/plate (0.05 < p < 0.10). There was a trend toward a lower reoperation rate in the stand-alone fusion group compared with the anterior plate group (0.05 < p < 0.10). Of the 59 patients, 3 patients (5.1%) in the stand-alone group underwent reoperation, including two at adjacent segments and the other reoperation was performed at a different center and appeared to have involved removal of the stand-alone device with fusion of the segment. In the anterior plate comparison group, 8 of 57 patients (14.0%) underwent subsequent surgery (four for pseudoarthrosis and four at an adjacent segment).

Fig. 1

The mean VAS neck and arm pain scores improved significantly in both groups with no significant differences between groups.

The stand-alone ACF group had outcomes similar to the allograft and anterior plate group, with both groups experiencing significant improvement in neck and arm pain scales and NDI (although trend for greater improvement in allograft/plate group) and a trend toward a lower reoperation rate after the stand-alone procedure. The results suggest that stand-alone ACF may be a viable alternative to allograft/plate procedures.

During development, the intervertebral disc (IVD) forms by segmentation of the embryonic axial skeleton which comprises the rod-like notochord (NC) surrounded by the somatic mesenchyme of the sclerotome. NC-derived signals are critical for induction and patterning of the sclerotome, which gives rise to the vertebral body. As the vertebrae form, the NC is segmented, forming the nucleus pulposus (NP) of the future IVDs. Embryonic notochordal cells (NCCs) have been hypothesized to be the precursors of adult NP cells (NPCs). We and others have shown from lineage tracing in mice that NP cells are of notochordal origin, suggesting NCCs are the progenitors of NP cells. We aim to define the molecular signature of the NC lineage at different developmental stages.

We generated mice in which NC and NP cells are marked by GFP by crossing our NC specific Foxa2 MNE-cre mice to Z/EG mice and isolated pure populations of cells by FACS. We have generated transcriptome data from isolated mouse embryonic (at E8.5-E10) NC and postnatal (at P2) NP cells. RNAseq data were obtained from these cells and analyzed bioinformatically.

In analyses of the transcriptomes of NC and NP cells, we have focused on (1) specific molecules that constitute the NC/NP cell niche (secreted factors, receptors, extracellular matrix [ECM] components), (2) unique markers for isolating the NC/NP cells at different time points, and (3) transcription regulators are essential for their differentiation. The rationale are as follows: many of the genetic risk factors identified so far for intervertebral disc degeneration (IDD) affect the ECM (e.g., COL9A1, aspirin, CHST3CILP, and ACAN) and knowledge of the composition of the extracellular niche would be important for interpreting genetic association data and will also guide us in designing appropriate ECM and growth factor support for maintaining isolated NCCs and NPCs. Our NCC data compared with published E8.0–E8.5 NC microarray expression data showed a high degree of similarity (> 0.8 Spearman rank correlation coefficient). Comparison of NCC transcriptome data with published data for mouse ES/iPS/EpiS cells showed a much lower correlation consistent with the progressive differentiation from early stages of development to NCCs. For NCCs, Wnt signaling was the major pathway, expression of genes involved in oxidative phosphorylation, and cell cycle/proliferation was enriched. The transcription factors characteristic of NCCs were Brachyury and Foxa2. There was enrichment for Hox genes. Hox genes control the body plan along the anterior and posterior axis, but their roles in NCC fate is not clear. For NPCs, the TGF-β, FGF, and VEGF pathways were dominant. Unlike NCCs, for NPCs, genes involved in ECM cell interaction (integrin signaling and focal adhesion) and Klf transcription factors dominated.

The spectrum of ECM genes expressed in NCCs differs significantly from NPCs, suggesting very different ECM niches for these cells. NCCs and NPCs also differed in terms of signaling pathways. The NPC characteristic genes correlated well with the known genetic risk factors identified so far for IDD and will therefore be a rich source of additional candidate genes for genetic risk factors for IDD.

Intervertebral disc (IVD) calcification frequently occurs with age as demonstrated by radiographic analysis of elderly spines and is enhanced in patients with scoliosis. In one study by Chanchairujira K. et al (Spine 2004;230:499–503), the degree of disc degeneration as measured by disc space height was significantly correlated with IVD calcification. Several systemic disorders such as hyperparathyroidism and chondrocalcinosis, which are related to calcium handling, arthritis, trauma, vertebral fusion, and infection, have been associated with IVD calcification. Our preliminary data suggest that ionic calcium content and expression of the extracellular calcium-sensing receptor (CaSR) are increased in NP and AF cells of human Thompson graded discs, however, a role in disc degeneration remains unknown.

Cells: Human NP and AF cells were incubated in culture media containing various concentrations of calcium (1.0, 1.5, 2.5, and 5.0 mM) a CaSR agonist (5 µM), or IL-1β (10 ng/mL) for 7 days. Lysates were extracted and the expression of aggrecan and type II collagen (Col II) were measured by Western blotting. IVDs: Caudal IVDs from the tails of 20- to 24-month-old steers were isolated and the vertebral bone was removed. IVDs were cultured for 4 weeks in culture medium containing calcium (1.0, 2.5, or 5.0 mM), or a CaSR agonist (5 µM). NP and AF tissues were subjected to guanidium extraction and Western blotting was performed to determine the expression of aggrecan and Col II. Histological sections were prepared to determine degree of mineralization by von Kossa staining and expression of alkaline phosphatase.

The expression of aggrecan and Col II decreased dose-dependently in both NP and AF cells following incubation with calcium or the CaSR agonist. A similar phenomenon was observed in the expression of aggrecan and Col II in IVDs following calcium incubation. In addition to decreases in Col II and aggrecan, increase in mineralization and expression of alkaline phosphatase was observed in calcium-incubated IVDs.

Our results suggest that changes in the local concentrations of calcium are not benign, and that activation of CaSR may be a contributing factor in IVD degeneration.

Tissue engineering aims to combine isolated cells, engineered materials and small molecule biochemical factors to generate neotissues with specific form and function to replace or repair damaged or degenerate native tissue. Intervertebral disc (IVD) degeneration directly causes back pain, and understanding how to regenerate this tissue may help alleviate this costly global problem. Several studies have combined isolated nucleus pulposus (NP) disc cells with novel scaffold materials to produce promising therapeutics toward IVD repair. We have taken three avenues toward IVD tissue engineering: culturing isolated IVD cells on continuous expansion surfaces to enhance cell phenotypes, utilizing novel injectable hydrogels for cell delivery to intact discs, and production of 3D printed scaffold geometries enhancing disc matrix production by seeded NP cells.

Bovine NP cells were isolated from caudal discs of freshly slaughtered steer (∼ 24 months) obtained from a local slaughterhouse. Bovine NP cells are expanded on either tissue culture plastic with two passages, or on highly elastic silicone rubber dishes which slowly expands the surface from 12 to 78 cm² and marker gene expression is compared. Isolated cells are labeled with fluorescent membrane binding dye, and cells are mixed with an injectable, chitosan/hyaluronic acid hydrogel. Approximately 100 µL of cell/gel (10⁶ cells/µL of gel) mixtures is injected into isolated whole bovine discs (obtained as described earlier, with vertebral bone drilled down to the cartilage end plate). Discs are then placed into a custom bioreactor, and dynamic diurnal loading is applied to the injected discs. After 14 days, localization and viability of injected cells is assessed by confocal microscopy. For 3D printed constructs, 10 × 10 × 0.3 mm plastic scaffolds were printed using a desktop 3D printer, with pore size of approximately 700 µm. Overall, 5 × 105 bovine NP cells were seeded on scaffolds, and cell viability, DNA content, proteoglycan content, and collagen type II content was assessed after 21 days in culture.

When cultured on elastic silicone dishes, continuous expansion of bovine NP cells preserve cell phenotype and promotes higher aggrecan and collagen type II expression compared with tissue culture plastic controls. NP cells embedded in a hydrogel and injected into whole discs were localized throughout the discs. Cells also showed high viability after 14 days in culture. Bovine NP cells seeded on 3D printed orthogonal plastic scaffolds grow extremely well and fill in the large 700 µm pores over 21 days culture. The cultured constructs have high viability and produce ample aggrecan and collagen type II protein.

By combining three different approaches we show the following: (1) individual NP cells can be engineered to maintain superior phenotypic qualities compared with standard culture procedures, (2) combination of expanded cells with injectable hydrogels can be delivered to intact discs for potential repair, and (3) simple 3D printed scaffolds can promote NP matrix production by seeded cells. Combination of these avenues may further enhance IVD regenerative capacities.

A significant obstacle to the study of degenerative disc disease and therapeutic strategies to treat DDD has been the lack of a suitable animal model. Here, we detail a mechanistic investigation of the changes in the molecular phenotype of the cells within the intervertebral disc in a preclinical rodent model of IVD degeneration following needle puncture.

Using a stereotactic device and fluoroscopic imaging control, we injured four IVDs/tail using 12-week-old female wistar rats and a 26-gauge needle. The needle was directed completely through the IVD annulus fibrosus (AD) to emerge through the contralateral annulus. The needle was then retracted back into the NP and after 1 minute, the needle was slowly removed over a further minute. The animals were allowed to recover for 10 weeks following which they were humanely euthanized and the discs recovered for biochemical, immunohistochemical, and protein analysis (Western blots).

The healthy rat NP changes drastically 10-weeks following needle puncture injury such that the former notochordal cell-rich NP assumes a fibrocartilaginous phenotype by 10 weeks. Initially, there is an increase in the expression of the notochordal cell markers galectin-3 and brachyury beginning at 72 hours; however, these are undetectable by 10 weeks with only scant appearance of immunopositive cells. Before injury, there are barely detectable chondrocyte-like cell (CLC) markers such as carbonic anhydrase-12 and Sox9, however, following injury there is a steady increase in their expression maximizing by 4 to 8 weeks. The strong expression of the stemness marker Oct3/4 steadily increases its expression post injury that reaches a peak at 6 weeks; however, this stemness marker is undetectable at 10 weeks. A similar trend is seen with the cell signaling protein β-catenin that is barely detectable at baseline but is strongly expressed at 72 hours postinjury and steadily increases until 4 weeks and then decreases to lower level expression at 10 weeks. There is an increase in the expression of collagen types 1 and 2 beginning 72 hours postinjury with a continued increase through 10 weeks. Interestingly, there is a reciprocal relationship between the matrix metalloproteinases (MMPs) and the tissue inhibitors of MMPs (TIMPS). MMP-3 and MMP-13 become detectable at 8 to 10 weeks precisely following the steady increase in expression of the natural inhibitor TIMP-1 which is completely undetectable when MMP-3 and MMP-13 increase their expression. ADAMTS-4 gradually increases its expression beginning at 72 hours through 8 weeks but is undetectable at 10 weeks.

Here, for the first time, we present a novel method of inducing degeneration in the rat tail IVD disc and have quantified the changes in the molecular phenotype of the IVD over 10 weeks. The injured rat tail IVD goes through a significant alteration in cellular and extracellular configuration that suggests a failed attempt on the part of notochordal and stem cells to induce repair resulting in the development of a fibrocartilaginous NP. This animal model and our characterization in the changes that causes postinjury can be used to quantify the effects of potential biological therapies in the treatment of DDD.

Diabetes mellitus (DM) is a major health problem worldwide. Approximately 10% of all DM cases are type 1 (Juvenile onset) and the prevalence of type 1 DM among the under 20s continuously rise. DM is known to be an important etiologic factor for premature disc degeneration. Previous studies have reported higher incidence of degenerative disc diseases in patients with DM, relatively young age, than in the patients without DM. A glucose-mediated increase of oxidative stress is a major causative factor for the development of diseases associated with DM through senescence. However, little is known about relationship among DM, mitochondrial damage, oxidative stress, senescence of young intervertebral disc cells, and disc degeneration. The aim of this study was to investigate the effect of high glucose on mitochondrial damage, oxidative stress, senescence of nucleus pulposus (NP) cells, and disc degeneration.

Young nucleus pulposus (NP) and annulus fibrosus (AF) cells were isolated from 4-week-old rats, cultured and placed in either 10% FBS (normal control) or 10% FBS plus two high glucose concentrations (0.1 and 0.2 M) (experimental conditions) for 1 and 3 days. We identified and quantified the mitochondrial damage (mitochondrial transmembrane potential) and reactive oxygen species (ROS) for 1 and 3 days. We also identified and quantified the occurrence of senescence and telomerase activity. Finally, we determined the expressions of proteins related to replicative senescence (p53–p21) and stress-induced senescence (p16–pRB) pathways.

Two high glucoses enhanced the disruption of mitochondrial transmembrane potential (mitochondrial damage) in young NP and AF cells for 1 and 3 days compared with normal control. Two high glucoses increased the occurrence of senescence of young NP and AF cells in a dose- and time-dependent manner. Telomerase activity declined in a dose- and time-dependent manner. Both high glucoses increased the expression of p16 and pRB proteins in young NP and AF cells for 1 and 3 days. However, compared to normal control, the expressions of p53 and p21 proteins were decreased in young NP and AF cells treated with both high glucoses for 1 and 3 days.

The current study demonstrated that high glucose-induced oxidative stress accelerates premature stress-induced senescence of young NP and AF cells in a dose- and time-dependent manner rather than replicative stress. This may result in dysfunction of young NP and AF cells, leading to accelerated premature disc degeneration. Therefore, the prevention of excessive generation of oxidative stress by strict blood glucose control is important to prevent or to delay premature disc degeneration in young patients with DM.

Disc degeneration in the cervical spine is a prevalent clinical predicament often requiring surgery. Anterior cervical decompression and fusion (ACDF), the most commonly performed procedure, poses risks of pseudoarthrosis, and adjacent segment disease (ASD).^1,2 An emerging alternative treatment option is prosthetic total disc replacement (TDR),³ which preserves segmental mobility. Our group previously developed a biological TDR device using composite AF/NP disc-like construct with viable cells and mechanical properties analogous to the native discs in a rat tail model.⁴ In this study, we evaluated the in vivo efficacy of this tissue-engineered intervertebral disc (TE–IVD) in a beagle cervical model assessing radiological and histological parameters.

TE-IVD construction: Canine-sized TE–IVDs were constructed as previously described.⁴ Cervical IVDs from skeletally mature beagles were separated into AF and NP tissues; component cells were isolated and cultured in vitro. Cultured NP cells were seeded with alginate, injected into a predesigned mold, and encircled with two layers of an AF cell laden collagen gel. The combined construct was kept in media for 2 weeks as the surrounding annulus fibrous aligned and contracted until required TE–IVD diameter was attained.

Experimental Protocol: Overall, eight skeletally mature beagles were divided into the following two groups: the control group (n = 2) underwent discectomy with fully resected IVDs, and the experimental group (n = 6) underwent TE–IVD implantation postdiscectomy. Adjacent proximal segments served as internal healthy controls. Postoperative X-ray and MRI were taken at 2 and 4 weeks; disc height indices⁵ and NP hydration using a pre-established algorithm⁶ were analyzed. Beagles were humanely killed at 4 weeks for histological assessment.

TE–IVDs were successfully implanted postdiscectomy (Fig. 1A, B). At 2 weeks, MRIs of TE–IVDs revealed T2 high intensity with acute outer inflammation because of the surgical invasion, which faded by 4 weeks. At 4 weeks, TE–IVDs maintained position in the disc space with relatively increased T2 intensity, whereas discectomized segments manifested as black discs (Fig. 1C, D). These findings suggest that the implanted TE–IVDs engraft in the disc space despite significant biomechanical demands of the beagle cervical environment. In fact, disc height indices of the TE–IVDs and discectomized discs were 71 and 49%, respectively, of that of healthy control discs. Likewise, MRIs revealed that NP hydration of the implanted TE–IVDs was over 70% of that of healthy discs. Histological assessments further demonstrated chondrocyte-like cell viability in the TE–IVD, abundant proteoglycan content in the extracellular matrices, and substantial integration into host tissues without signs of immune reactions.

Fig. 1

(A, B) TE–IVD. (C, D) Sagittal and axial T2-weighed MR images of control/experimental segments.

Despite the severe local milieu of the beagle cervical spine owing to mechanical loading, our in vivo TE–IVDs when appropriately implanted, maintained their position and structure at 4 weeks. The TE–IVDs displayed dynamic adaptation to the host environment, with extracellular matrix production and cell proliferation. They further maintained disc height as well as NP hydration at 4 weeks with up to 70% viability as the normal healthy discs.

References

Nesterenko SO, Riley LH III, Skolasky RL. Anterior cervical discectomy and fusion versus cervical disc arthroplasty: current state and trends in treatment for cervical disc pathology. Spine 2012;37(17):1470–1474

Sugawara T, Itoh Y, Hirano Y, Higashiyama N, Mizoi K. Long term outcome and adjacent disc degeneration after anterior cervical discectomy and fusion with titanium cylindrical cages. Acta Neurochir (Wien) 2009;151(4):303–309, discussion 309

Kelly MP, Mok JM, Frisch RF, Tay BK. Adjacent segment motion after anterior cervical discectomy and fusion versus Prodisc-c cervical total disk arthroplasty: analysis from a randomized, controlled trial. Spine 2011;36(15):1171–1179

Bowles RD, Gebhard HH, Härtl R, Bonassar LJ. Tissue-engineered intervertebral discs produce new matrix, maintain disc height, and restore biomechanical function to the rodent spine. Proc Natl Acad Sci U S A 2011;108(32):13106–13111

Kim JS, Kroin JS, Li X, et al. The rat intervertebral disk degeneration pain model: relationships between biological and structural alterations and pain. Arthritis Res Ther 2011;13(5):R165

Grunert P, Hudson KD, Macielak MR, et al. Assessment of intervertebral disc degeneration based on quantitative magnetic resonance imaging analysis: an in vivo study. Spine 2014;39(6):E369–E378

Proximal junctional kyphosis (PJK) has traditionally been defined by a 10 degree or greater increase in kyphosis at the proximal junction as measured according to Cobb method. Especially patients who have advanced spine deformity are prone to PJK and it is related with aggressive treatment protocols. In this biomechanical study, we aimed to evaluate interspinous ligament complex disruption and facet joint degeneration on PJK development.

Randomly selected 21 sheeps were operated via posterior approach and pedicle screws were instrumented from T2 to T7. Three groups with seven samples were established to create junctional disruption. First group selected as control group (CG), of which posterior soft tissue and facet joints were preserved intact. In the second group (spinous group, SG), interspinous ligament complex which one segment cranial to UIV has been transected, and third group (facet group FG) where facet joint excision was performed. 25 N, 50 N, 100 N, 150 N, and 200 N forces applied at frequency of 5 Hz as 100 cycles axial to the samples. To determine strength of proximal junctional area in static loading 250 N, 275 N, and 300 N forces was applied. Changes in the proximal junctional region were defined radiologically. Lateral X-ray views were taken to measure interspinous distances, kyphosis angles, and discus heights. Abnormal PJK was defined by a proximal junctional angle greater than 10 degree and at least 10 degree greater than the corresponding preoperative measurement.

In CG group, average interspinous distance was 6.6 ± 1.54 mm and kyphosis angle was 2.2 ± 0.46 degree before biomechanical testing, and they were measured as 9.4 ± 1.21 mm and 3.3 ± 0.44 degree respectively after forces applied to samples. In SG group, average interspinous distance was 6.2 ± 1.71 mm and kyphosis angle was 2.7 ± 1.09 degree before the experiment, and they were measured as 20.8 ± 5.66 mm and 15.1 ± 2.33 degrees, respectively, after biomechanical testing. In FG group, average interspinous distance was 4.8 ± 1.15 mm and kyphosis angle was −1 ± 4.14 degree before experiment, and they were measured as 11.1 ± 1.96 mm and 11 ± 2.87 degree, respectively, after forces applied to samples. Statistically significantly junctional kyphosis development was detected on both FG and SG group than group control group (p < 0.05). PJK was seen significantly more frequently on SG group than FG group (p < 0.05). Disc distances were similar in all groups (p > 0.05).

Protecting interspinous ligament complex and facet joint on surgical treatment of spine deformity is mandatory to prevent PJK. To our knowledge, this is the first biomechanical study that reveals that the interspinous ligament complex is more effective in preventing PJK development than facet joints.

A majority of the biomechanical in-vitro studies depend on virtual coordinate systems. These are in most cases based on anatomic landmarks. Typically, the vertebral body is marked by passive or active markers and tracked with a motion capture. Each vertebra needs to be referenced with a digitizing probe. The precision of this registration and the consecutive orientation of the body coordinate system are mainly depended on distinguishable anatomic landmarks. Hence, referencing of vertebral bodies is quite error prone. Further problems arise if the reference procedure has to be redone during testing process or the anatomic landmarks are not accessible because of the operative procedure or testing set-up.

To address the problem of repeatability, we developed a set of small marker screws that have specially designed screw heads (Fig. 1). The spherical tip of the digitizing probe can be fitted into the cutout cone of the screw head with the result that the referenced point is equivalent to the point of intersection of the screw axis and the perpendicular base of the cone. Accordingly, if the screws are firmly attached to the bone, it will be possible to reference the points very reliable. The following steps did this: 1st step: Insertion of three or four marker screws into each vertebral body. The positions can be freely chosen as long as the motion capture system is able to generate a coordinate system. Any interference with the operative procedure or testing setup should be prevented at this point. 2nd step: Performing a CT/MRI scan of the specimen. In most cases, this has to be done to exclude compromising defects anyway and consequently, no extra effort is necessary. 3rd step: Referencing of the body coordinate systems with the aid of the marker screws. This can be repeated during the testing procedure if necessary. 4th step: Completion of the in vitro testing procedure.

Transformation matrices could correct the virtual shift from the referenced body coordinate systems to the anatomically aligned coordinate systems taken from CT scan. This was done by determination of the marker screw heads in the depicted volume and virtual regeneration of the referenced body coordinate systems from the 3rd step. Then the coordinates for the generation of the anatomically aligned coordinate systems can be obtained. On the basis of the two coordinate systems, a transformation matrix can be calculated to shift data from one system to the other. In consequence, it was possible to apply each transformation matrix to the data set obtained during the in vitro testing procedure to shift it virtually to the respective anatomically aligned coordinate system.

The presented algorithm facilitates the link between the kinetic data from in vitro testing procedures and the precise anatomical data from 3D imaging. Accordingly, it might help to understand complex motion parameters (e.g., FHA) by plotting them into the 3D volume.

Fig. 1

Marker screw and digitizing probe.

The objective of decompressive surgery for lumbar or cervical stenosis is to treat the compressive pathology while minimizing iatrogenic destabilization of the spine. The surgical technique has consequently evolved from the radical laminectomy to a facet-sparing laminectomy and more recently to midline preserving techniques including bilateral laminotomy. Cadaveric studies have supported and characterized the biomechanical advantages of the bilateral laminotomy over facet-sparing laminectomy. In this study, we characterize and compare outcome and long-term follow-up between patients who have been treated with either of these two techniques at our institution.

We reviewed 100 patients comprising 50 who underwent bilateral facet-sparing laminectomy and 50 who underwent bilateral laminotomy. Clinical outcome measures include reduction in pain as assessed using visual analog scale. Biomechanical outcome measures included segmental motion at the operated segment as measured on postoperative flexion–extension X-rays obtained at long-term follow-up.

Analyses of each of the surgical technique cohorts were performed. Clinical outcome as assessed by visual analog scale ratings was comparable between the two groups of patients undergoing either of bilateral laminectomy or bilateral laminotomy. An increase in the segmental angular movement at the operated level as measured from flexion extension studies was less in the patients undergoing bilateral laminotomy as compared with those undergoing bilateral laminectomy.

The bilateral laminotomy achieves successful decompression of spinal stenosis while preserving biomechanical stability of the involved spinal segments. For properly selected patients, this may provide a surgical option with clinical and biomechanical outcomes which are superior to those provided by facet-sparing laminectomy, which has supplanted to original radical laminectomy. Sparing of the midline osteoligamentous structures, as achieved using the bilateral laminotomy, represents a further advancement in surgical technique in the treatment of spinal stenosis, providing satisfactory clinical outcomes while further minimizing disruption of the normal spinal biomechanical stability.

The gold standard treatment for degenerative lumbar listhesis is decompression with fusion. According to a SPORT trail, 35% of patients with this condition present with additional symptomatic stenosis most commonly on the adjacent segment. However, the most appropriate surgical technique to treat the stenosis adjacent to the instrumented segment remains controversial. Extended fusion with open decompression could lead to adjacent segment disease; simple decompression without fusion might lead to clinically relevant instability at the index level. To date, there is no study evaluating the biomechanical impact of decompression procedures in this clinical scenario. The presented work is the first to analyze the mechanical effect of minimally invasive (MI) and open decompression procedures adjacent to instrumented segments in the lumbar spine.

Tested conditions: Seven cadaveric lumbar spines were tested. The entire lumbar spine was assessed intact (baseline) and for the following conditions: (1) Instrumented fusion at L4/L5. (2) MI decompression through a tubular retractor at L3/L4 with a unilateral approach for bilateral internal decompression and complete removal of the flavum ligament. (3) Additional bilateral partial facetectomy at L3/L4 (20% of the facet joints). (4) Laminectomy at L3/L4. Mechanical testing: Specimens were carefully cleaned of muscular tissue and potted at T12 and S2–S4. Nonconstraining, nondestructive pure moment (torque) loading (7.5 Nm) was applied to each specimen through a system of cables and pulleys in conjunction with a standard servohydraulic test system. Loads were applied in 1.25 Nm increments until the maximum load was reached. Each condition was tested for flexion extension, lateral bending, left and right axial rotation, and compression. The range of motion (ROM) of each segment was assessed stereophotogrammetrically by capturing the three-dimensional displacement of infrared-emitting markers which were rigidly attached to each vertebra from L1–S1. ROM was measured in degrees and used to quantify spinal stability. One-way repeated measures analysis of variance (ANOVA) followed by the Fisher least significant difference test were used to compare ROM.

All data are shown as normalized ratio. Compared with intact L3/L4 after L4/L5 fusion, MIS decompression significantly increased the L3/L4 ROM by 13% (p = 0.034) for flexion extension (20% more than baseline) and 23% for axial rotation (p = 0.003) (26% more than baseline). Partial facetectomy further increased the ROM by 15% for axial rotation (p = 0.032) (46% more than baseline) but not for flexion extension. Laminectomy further increased the ROM for flexion extension by 12% (p = 0.05) (38% more than baseline) and for axial rotation by 17% (p = 0.023) (58% more than baseline). There were no significant changes for lateral bending or compression tests for any tested condition. Looking at the overall motion of the lumbar spine, L4/L5 fusion decreased flexion extension by 20% (< 0.001) and axial rotation by 19% (p < 0.001). With each decompressive procedure, the overall motion returned to almost normal in a stepwise manner reaching 95% of baseline after laminectomy.

Mechanical alterations of MI decompression adjacent to fused segments are comparable to mechanical alterations of these procedures without adjacent fusion shown in other studies. Therefore, adjacent fusion does not significantly increase instability of MI decompression. The preservation of the facet joints is crucial for segmental stability. Laminectomy adjacent to fused segment causes an up to 58% increase in segmental ROM and is therefore not recommended in the presented clinical scenario.

Long instrumented posterior fusion constructs to the lumbosacral spine have a significant rate of pseudoarthrosis and S1 screw failure. With the increasing popularity of Sacral Alar-Iliac (S2AI) fixation with its purported advantages of (1) decreased implant profile and (2) obviating the need for a lateral offset connector, the biomechanical properties with respect to S1 screw strain remain unknown. We set out to compare the biomechanical effect of S2AI versus traditional iliac screw fixation on S1 screw strain.

Five fresh-frozen human cadaveric specimens were instrumented from L2–pelvis, maintaining all osteoligamentous structures, with bilateral titanium 6.0 × 40-mm pedicle screws and 5.5-mm cobalt–chromium rods. Bilateral S1 pedicles were instrumented with 8.0 × 50-mm screws that were centrally cored out and two uniaxial strain gauges inserted at 0 and 90 degrees. S2AI fixation and/or iliac fixation with 8.0 × 80-mm titanium pedicle screws was performed to evaluate the following four different constructs: (1) bilateral S1 screws (control); (2) bilateral S2AI; (3) bilateral iliac; (4) hybrid (S2AI with contralateral iliac). Bilateral S1 screw strain was measured (microstrain), and pure moment loads (12.0 Nm) were applied in axial rotation (AR), flexion extension (FE), and lateral bending (LB). One way repeated measure ANOVA was used to analyze the S1 screw strain data.

Compared with S1 screws alone, both S2AI fixation and iliac fixation significantly reduced sacral screw strain in FE by 58 and 67%, respectively (p < 0.05), in AR by 35 and 41%, respectively (p < 0.05), while no significant difference in LB for either construct (p > 0.05). Hybrid constructs demonstrated a significant reduction in only FE, with reduction in screw strain by 56% for S2AI fixation and 59% for iliac fixation, with no difference in AR and LB moments. When S2AI fixation and iliac fixation were compared, there was no significant difference in screw strain for all bending moments (p > 0.05). Similarly, hybrid constructs demonstrated no side-to-side significant difference between S2AI fixation and iliac fixation for all bending moments (p > 0.05).

Both S2AI fixation and iliac fixation provide significant reduction in S1 sacral screw strain compared with sacral fixation alone. Bilateral S2AI fixation is a viable and biomechanically comparable to alternative traditional iliac fixation, and presents another option to achieve protection of the S1 sacral screws for long segment constructs to the pelvis.

Anterior plate constructs for cervical discectomy and fusion have been linked to postoperative dysphagia, increased operative times, and wider surgical exposures. Several “low profile” integrated stand-alone spacers (SAS) have been developed. While these spacers have demonstrated successful clinical outcomes and similar biomechanical stability to anterior plate constructs in single-level fusions, their biomechanical stability in multi-level constructs has not yet been established.

Twelve human cadaveric cervical spines (C2-T2) were nondestructively tested with a six-degree-of-freedom simulator under axial rotation (AR), flexion-extension (FE), and lateral bending (LB) loading. After intact analysis, each specimen underwent sequential instrumentation and testing: (A) C5-6 spacer/plate with C6-7 SAS; (B) C5-7 SAS; (C) C5-7 spacer/plate. Range of motion (ROM) data was obtained and analyzed with paired t-tests and Bonferroni correction.

The 2-level plate construct significantly reduced flexion-extension ROM compared to the 2-level SAS (5.6 ± 3.4 degrees versus 11.6 ± 4.6 degrees, respectively; p < 0.05). There was a significantly increased segmental ROM in the 2-level SAS construct compared to the 2-level hybrid construct in flexion-extension as well (11.6 ± 4.6 degrees versus 7.2 ± 2.4 degrees, respectively, p < 0.05). There was no significant difference in lateral bending and axial rotation (p > 0.05) between the three different 2-level constructs.

Our study found that hybrid and 2-level SAS constructs are comparable to conventional anterior plate constructs in lateral bending and axial rotation, but there was an increase in flexion-extension motion allowed with constructs that incorporated a SAS. Stand-alone cervical spacers with integrated screws for hybrid and 2-level SAS constructs are reasonable alternatives to two-level plate fixation; however, clinical trials are necessary to determine if the increased ROM in flexion-extension noted in the SAS constructs translates to clinical outcome.

The AOSpine Thoracolumbar Spine Injury Classification System was recently published and combines elements of both the Magerl system and the Thoracolumbar Injury Classification System (TLICS); however, the injury severity of each fracture has yet to be established. The objective of this study is to develop a validated regional and global injury severity scoring system for thoracolumbar trauma.

A survey was sent to 100 AOSpine members from all six AO regions of the world (North America, South America, Europe, Africa, Asia, and the Middle East). Each respondent was asked to numerically grade the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System including the morphology, neurologic grade, and patient-specific modifiers. A grade of zero was considered to be not severe at all, and a grade of 100 was the most severe injury possible.

A total of 74 AOSpine surgeons from all six AO regions of the world numerically graded the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System to establish the injury severity score. The reported fracture severity increased significantly (p < 0.0001) as the subtypes of fracture type A and type B increased, and a significant difference (p < 0.0001) in severity was established for burst fractures with involvement of two versus one end plates. Finally, no regional or experiential difference in severity or classification was identified.

Development of a globally applicable injury severity scoring system for thoracolumbar trauma is possible. This study demonstrates no regional or experiential difference in perceived severity or thoracolumbar spine trauma. The AOSpine Thoracolumbar Spine Injury Classification System provides a logical approach to assessing these injuries and enables rational strategies for treatment.

The aim of this study is to describe the results obtained in 44 patients, all between 20 and 65 years, operated between 2011 and 2013 with the diagnosis of thoracic and lumbar vertebral fractures posttraumatic, treated in our department. In all cases, we used the same technique, which consists of fixing two levels above and two levels below the fractured vertebrae including it in the osteosynthesis system getting full or partial reduction of the fracture. After the fracture consolidation, we proceeded to the removal of the implant between 6 to 9 months after surgery. The indication was always surgical treatment with temporary fixation without arthrodesis. After the removal of the osteosynthesis material, all patients recovered the capacity of flexo-extension of the thoracolumbar spine. The patients returned to their previous levels of daily life and sport. It took them 35 days on an average to return to work and from 6 to 9 months to their sports activities. Patients were followed for 1 year after surgery.

A total of 44 patients were evaluated, 34 men and 10 women. The complaint was for posttraumatic back or low back pain by falls from their own height standing or sitting, in the 72% of cases, with no more than 48 hours of evolution that did not get better with rest and got worse with mobilization. The rest of the cases were traffic accidents. All patients were studied by MRI and X-rays. All fractures were treated by the same surgeon within the first 72 hours of making the diagnosis. Fractures were divided as follows: D9 (1 case), D10 (7 cases), D11 (6 cases), D12 (11 cases), L1 (10 cases), L2 (7 cases), L3 (1 case) and L4 (1 case). Overall, 83% of cases were type A fractures according to the AO classification, and the remaining 17% were type B, which were associated with rupture of the posterior wall and invasion of the spinal canal. Only two fractures had neurological and motor compromise C, according to Frenkel classification. The rest of the fractures had Frenkel E.

All patients returned to their usual physical activities, even those who played sports with the exception of the two Frenkel C. As postoperative complications, patients had scar hygromas that were cured with puncture and compressive bandage. Everyone referred complete or partial improvement of their symptoms. Only in one case, we had a postoperative complication which was the rupture of one of the lower transpedicular screws of the system at 3 months; after the removal of the implant at 6 months, the pain disappeared without complications.

This method, temporary fixation without arthrodesis of five levels, is usually used in our department to treat thoracolumbar fractures. Patients had no postoperative complications except one patient who presented a ruptured of a transpedicular screw but no reoperation was needed. In all cases, there was a complete remission of symptoms and return to normal activity.

Experimental studies of the spinal cord before and after injury caused by trauma are necessary to evaluate the new therapeutic options, such as stem cell therapy. In those experiments, it is mandatory to measure motor and sensitive function adequately to the bias and increase true results. The objective is to describe the technique used to obtain the compound and extracellular action potentials in the spinal cord.

To obtain the spinal cord compound action potentials (CAPs), the spinal cord of the rat spine was immediately placed in a Perspex chamber covered with Sylgard and superfused at (2 mL/min) with Krebs solution and glucose. The solution was maintained at pH 7.2 and 5% CO₂/95% O₂. The Ag/AgCl needle electrodes fixed the tissue in the chamber. The needle electrodes were connected to an operational amplifier and to a programmable signal conditioner model. The electrical stimulation was done by suction bipolar electrode placed in the inferior segment of the spinal cord. The electrode was connected to an analogical stimulator, which delivered stimulus at 01 Hz for a 0.2 milliseconds duration. The data always began to be recorded after 15 minutes of stimulation to ensure the stability of the preparation. The recordings of the CAPs were made during 30 minutes directly to an AxoScope software. The events were analyzed by the Clampfit software. To acquire extracellular action potential, the spinal cord was cooled in Krebs solution, previously gassed with a 95% O₂ and 5% CO₂ mixture to obtain a pH value of 7.2 to 7.4. A 400 µm thick coronal section was made. The spinal cord slice was recovered during at least 30 minutes at 32°C in Krebs solution and transferred to a submersion-type recording chamber with Krebs solution, 95% O₂ and 5% CO₂. Extracellular recordings were made using 5 to 10 MΩ resistance glass pipettes. An iridium stimulation electrode was connected to an analogical stimulator and positioned at the proximal side of the tissue to deliver electrical stimuli (0.1 Hz, 0.2 ms). The recording electrode was placed in the opposite or distal side. The recordings were performed using an amplifier connected to a programmable signal conditioner. The experiments were recorded during 1 hour. The data were retrieved by an AxoScope software and analyzed by the Clampfit software.

The compound and extracellular action potential could be generated in both experiments indicating that the functional analysis of spinal cord neurons can be assessed by in vitro stimulation of the spinal cord tissue or its slice. The control values for the amplitude of CAPs was 4.4 ± 0.3 mV (n = 3). The rise time of the CAPs was 1.73 ± 03 ms; the decay time was 4.2 ± 2 ms, and the duration was 4.2 ± 0.8 ms. The analysis of the extracellular action potentials showed that the mean amplitude, rise time, decay time, and duration were 2.17 ± 0.3 mV, 0.4 ± 0.2, 4 ± 1, and 2.1 ± 0.2 ms, respectively.

The analysis of compound and extracellular action potential can be used as outcome measurement of spinal cord functionality. This can measure more precisely, for example, the neuronal repopulation and motor and sensitive recovery of spinal cord injury.

The use of minimally invasive techniques for spinal stabilization (MISS) is now widespread because of the theoretical advantage of lesser surgical aggression. However, there is no definitive evidence of its real advantage comparing to traditional open surgery (TOS). In this study, the authors compare both techniques according to safety and efficacy for the treatment of spinal instability.

This is a retrospective cohort study analyzing the records of the patients submitted to posterior dorsal or lumbar stabilization by MISS or TOS as treatment of instability because of trauma, infection, or tumor in a single center in the last 5 years (2009–2013). We compared both techniques according to efficacy (postoperative pain and deformity correction) and safety (accuracy of screw insertion, surgical and length of surgical time and hospital stay, complication occurrence Đ mortality, infection, neurological deterioration, instrumentation failure). Statistical analysis was performed with SPSS(R)17.0 surgeon preference dictated the technique chosen for each case.

A total of 69 patients were treated, with a median follow-up of 21.6 ± 15 months. The populations (MISS/TOS) were not significantly different in the following: age, general medical status (ASA score), instability score (TLICS and SINS), osteoporosis incidence, lesion location, type of pathology, previous neurological state, or nonfusion risk factors. There was no statistical difference in postoperative pain (p = 0.715) and immediate and late deformity correction (p = 0.577 and p = 0.689). Screw insertion accuracy was significantly less in TOC (p = 0.001) leading to more cases of revision surgery. Surgical time was not significantly different (p = 0.08). Hospital stay was significantly shorter in MISS. Complication incidence was rare, but postoperative infection and neurological worsening was more frequent in TOS.

MISS is as effective as TOS and significantly safer than the later in what concerns to screw insertion accuracy and need for revision surgery. It does not take more OR time; and the length of stay at the hospital is shorter.

Patients with unstable mid and lower lumbar burst fractures require surgical treatment to relieve pain, address paralysis, and stabilize the spine to prevent further segmental deformity. However, controversy remains regarding the optimal surgical treatment. The purpose of this study is to examine the efficacy and safety of corpectomy and expandable cage placement via a single-stage posterior approach for unstable mid and lower lumbar burst fractures (below the L3).

A total of 11 patients underwent single-stage posterior-only vertebral column resection and vertebral body reconstruction using an expandable cage. Neurologic status was classified using the American Spinal Injury Association (ASIA) Impairment Scale, while functional outcome was analyzed using a visual analog scale (VAS) for back pain. Segmental Cobb angles were measured above and below the fractured vertebral body preoperatively, immediate postoperatively, and at the last follow-up.

The preoperative neurologic status was ASIA grade E in two patients, grade D in five patients, grade C in two patients, and grade B in two patients. Postoperatively, neurologic stability was demonstrated in three patients (27%), and eight patients (73%) showed improvement in the ASIA grade. The mean preoperative VAS score was 8.3, which decreased to 4.5 postoperatively, and to 1.8 at the final follow-up. The mean preoperative segmental lordotic angle was 9.2 degrees, which increased to 16.9 degrees postoperatively, and decreased to 15.1 degrees at the last follow-up. The mean operating time was 208.8 minutes, and the mean blood loss was 588 mL. Regarding surgical complications, one patient experienced a dural tear and one patient demonstrated cage subsidence.

The results of this small series suggest the feasibility, efficacy, and safety of this surgical option for unstable mid and lower lumbar burst fractures. This technique from a single posterior approach offers several advantages over traditional anterior or combined approaches using strut graft or nonexpandable implants.

In posterior ligamentous complex injury (PLC), surgery is indicated in the treatment algorithms of thoracic and lumbar fractures. That is why its research is of a great importance, taking into consideration the magnetic resonance imaging (MRI), as historical “gold standard.” As the MRI is not always available or at times it is contraindicated, the use of ultrasound is proposed. Our purpose is to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ultrasound to diagnose PLC injuries in thoracic and lumbar fractures.

A protocol is designed before the start of the study, being approved by the Ethics Committee, deciding to perform an ultrasound to all of the patients with PLC admitted with fractured thoracic and lumbar spine, between April 2013 and July 2014. Patients with neurological and life-threatening risks were excluded. The ultrasound and MRI reports were performed by different radiologists without knowledge of the results of other studies. The result of the MRI is considered “gold standard,” and in case of operated patients, there were intraoperative findings. Data were analyzed with STATA 12.

A total amount of 56 patients were recruited, with 7 cases of PLC injuries according to our “gold standard.” The ultrasound as diagnostic tool obtained the following results: sensitivity 0.9999 (95% CI, 0.59–1), specificity 0.9608 (95% CI, 0.8603–0.9966), PPV 0.7778 (95% CI, 0.4427–0.9465), and NPV 0.9999 (95% CI, 0.9131–1).

The ultrasound would be useful to diagnose the PLC injuries in thoracic and lumbar fractures.

Studies have shown that lumbar fusion may lead to increased degeneration at the adjacent level. However, the issue of further degeneration around the fusion area is controversial. There is debate whether it is the natural history of progressive degeneration or increased stress from the fusion which causes the further degeneration. Goal of our study was to compare the incidence of progressive degeneration and need for subsequent surgery between patients who were treated nonsurgically or with fusion for a thoracic or lumbar level fracture.

The commercially available PearlDiver database and insurance billing codes were used to identify 3,699 patients diagnosed with thoracic fracture and 5,016 patients diagnosed with lumbar fracture in 2007. For both the thoracic and lumbar fracture cohorts, patients were divided into subgroups based on procedural codes: those who underwent fusion surgery and those who were treated nonsurgically. Each of those subgroups was further divided into patients who were diagnosed with intervertebral disc degeneration within1, 2, and 3 years from their initial treatment, and of those patients, how many had a follow-up surgery. We used chi-squared statistical analysis to compare incidences of disc degeneration and follow-up surgery between the fusion and nonsurgical groups.

Of the 3,699 patients diagnosed with thoracic fracture, 3,215 (86.9%) were treated nonsurgically and 117 (3.2%) underwent thoracic fusion surgery within 90 days. Within 3 years, 147 patients from the nonsurgical subgroup and fewer than 11 from the fusion subgroup were diagnosed with thoracic disc degeneration. From the nonsurgical subgroup, 11 (0.3%) patients underwent a thoracic surgery related to disc degeneration, compared with zero from the fusion group (p > 0.05). From 5,016 patients diagnosed with lumbar fracture, 4,371 (87.1%) were treated nonsurgically and 150 (3.0%) underwent lumbar fusion. Within 3 years, 503 (11.5%) patients from the nonsurgical and 35 (23.3%) from the fusion subgroup were diagnosed with lumbar disc degeneration (p < 0.05). From the nonsurgical subgroup, 42 went on to have lumbar surgery related to disc degeneration, compared with fewer than 11 from the fusion subgroup (exact number suppressed because of the privacy limitations).

In the thoracic region, fusion surgery as treatment for thoracic fracture does not appear to increase the likelihood of disc denegation and future surgery compared with conservative treatments. On the contrary, in the lumbar region, initial fusion surgery appears to increase the incidence of disc degeneration and future surgeries, as well as nonsurgical procedures.

The concepts of “tissue-sparing surgery” and “mini-invasiveness” are gradually involving the surgical approach to spine pathologies, both traumatic and degenerative.

The aim of the study is to evaluate the fracture healing model in case of unstable thoracolumbar vertebral fractures surgical treatment, treated by posterior percutaneous transpedicular stabilization (PPTS). Since March 2011, 89 patients with this fracture pattern, without neurologic involvement (according to ASIA classification) were enrolled in the study. Patients were randomly divided into two homogeneous samples. PPTS (with rods and screws) and standard posterior open approach were performed in patients of groups A (46 patients) and B (43 patients, control), respectively. A clinical and radiographical follow-up was performed respectively at months 1, 3, 6, 12 (according to visual analog scale [VAS] and Oswestry Disability Index [ODI]) and at months 1, 6, 12 (dynamic radiographic studies in the last two times). Segmental kyphosis and wedge-shaped deformity amount of the involved vertebral bodies, were measured pre- and postsurgery. At month 12, a CT scan with 3D reconstruction and analysis of chrome-densitometry was obtained. The data were analyzed by mean of the Kaplan–Meier curve (results yielding p < 0.05 were considered statistically significant).

Clinically, in group A, we have observed a progressive and more rapid VAS and ODI scores improvement. Vertebral body collapse or kyphosis progression was not observed. There were no “fixation failure” and no patient underwent revision surgery. The 3D reconstructions and the chrome-densitometry evaluation at month 12 showed a more homogeneous and organized trabecular architecture recovery in group A (vs. group B). The PPTS acts as an “angular stability” fixation system; it allows a “biological” healing process (according to Wolf law), producing better clinical and radiographical results.

Unstable thoracolumbar fractures PPTS is an effective alternative to the classic open standard treatment. The advantage of mini-invasive spine surgery and “biological” healing process explain these better results and faster recovery times. This technique represents a safe and effective treatment, in terms of clinical and radiographical findings.

Spinal cord injury occurs mainly in young healthy individuals, causing motor impairment and temporary or sensory loss and leading to chronic disability. An attractive possibility of treatment for TRM is the use of stem cells for restoration of neural cells in the spinal cord. Support Matrices for use in cell therapy must be able to provide structural and microenvironmental support to ensure the viability of the transplanted cells and to facilitate integration in the target tissue.

Biocompatible polymeric films composed of polylactic acid-co-acid (PLGA) polymer nanofiber polypyrrole (PPy) were used polypyrrole nanofibers and films made containing 10% (W/W) PLGA in PPy by solvent evaporation method were synthesized. The PPy nanofibers showed electrical conductivity of semiconductor and the dispersion of the nanofibers in PLGA resulted in PPy films with fibrous topographical morphology with suitable for use as scaffolds for cell growth driven by PPy nanofiber voids. Cell toxicity test method of extraction was performed. Samples of the polymers were maintained in DMEM culture medium obeying the proportions established by ISO 10993 (2013) by 24, 48, 72 hours, 7 and 14 days. After each time period, NIH3T3 fibroblasts were cultured for 24 hours with the film exposed to the environment, and then was held cellular toxicity test by MTT assay. Wistar rats were anesthetized and underwent laminectomy of the eighth thoracic vertebra. On the local display of the spinal cord was placed a cut polymer approximately 3 mm wide and 8 mm long. The motor recovery of the animals 24 hours and 7, 14, and 28 days after injury was assessed. To assess the degree of inflammation generated by the polymer in tissues other than the spinal cord, a 1 cm incision in the flank and placement polymer was performed. In the region against lateral incision was performed only. Histological evaluation of the spinal cord and the fabric flank was held.

The electrical conductivity of PPy fibers showed values of 8.10 to 4 S/cm, lying within the range of semiconductors. The molecular structure of PPy was evaluated in the range of 400 to 4,000/cm and all spectra were similar. There was no change in cell viability after exposure of the cells to the conditioned medium with the polymer in both seasons. Cell viability was maintained at 100% when compared with the control. The motor functional assessment of mice showed no alteration in any evaluation period are because of the surgical procedure or a possible effect of inflammatory irritation of the polymer on the spinal nerve tissue. Histological evaluation showed no changes suggestive of inflammation or infection of the marrow tissue adjacent to the polymer or the flank of the animal tissues.

PLGA/PPy polymer has conductivity expected for semiconductors and structural heterogeneity, without any type of cell toxicity in periods. The polymer is safe to be used as a scaffold in the TRM model because it does not cause any functional, structural, or inflammatory change.

Type B3 thoracic and lumbar fractures are often found in spines with previous hyperossification processes. They occur most frequently because of the high-energy trauma in a healthy spine and as fall-related domestic injury in a spine affected by hyperossification. They are less frequent than type B3 cervical spine fractures.

Between March 2003 and March 2014, 39 patients with type B3 injuries (Magerl classification) were treated in our centers. The thoracic spine was involved in 28 and the lumbar spine in 11 patients. The patients' average age was 64.5 years, with a range of 33 to 87 years. There were 6 women and 33 men. Overall, 10 fractures occurred in previously healthy spines, 9 and 20 were in AS- and DISH-affected spines, respectively.

All nine patients with AS suffered low-energy fractures while patients with previously healthy spines had high-energy injuries in eight cases and low-energy in two. The patients with DISH had both low-energy (12) and high-energy (8) fractures. Type B3.1.1 fractures were diagnosed in 4 patients with AS and 10 patients with DISH, and 2 in previously healthy patients. Type B3.1.2 fractures were found in one patient with AS, four patients with DISH, and three previously healthy patients. Type B3.2 fracture occurred in two patients with a previously healthy spine, in three patients with AS, and three patients with DISH. Type B3.3 fractures were in five patients with previously healthy spines and in to with DISH. Neurological deficit was found in nine injured patients. Overall, 38 patients had an elevated BMI, ranging from 25.1 to 42.2; the average value was 31.1, which is within grade 1 obesity. Only one patient had BMI 24.7 kg/m². Associated injuries were found in 18 patients, mostly in those with high-energy trauma, one of them suffered with traumatic aneurysma dissecans of aorta. A total of 33 patients were treated surgically, 6 conservatively. Posterior long stabilization was performed in 22 patients who had either AS or DISH conditions; 11 patients had a short spinal stabilization. Three patients with short instrumentation were operated from anterior as well. Complications included early infection in three patients, cerebrospinal fluid fistula in one, urinary tract infection in three, and confused state of mind in two patients. We also found multiorgan failure (three), respiratory insufficiency (one), sespis (one), and three patients died. Survived patients healed well.

In the majority of publications, these injuries are reported in patients suffering from hyperossification disorders such as AS or DISH. In patients with healthy spines, they occur less frequently and the traumatic hyperextension mechanism must have great intensity. Fractures of a hyperossified spine are related to obesity and this was also confirmed by our study in which all patients were overweight or obese. This factor plays an important role in the hyperextension mechanism that produces a sudden overcoming of the resistance of a spinal segment to force, resulting in a type B3 fracture.

In patients with AS and DISH, the diagnosis may be delayed because these patients suffer from chronic spine pain and the pain due to fracture may be attributed to an accelerated chronic condition.

Degenerative spondylolisthesis refers to slip of one vertebral body over the one below as a result of degenerative changes in the spine. Mild-to-moderate symptoms are initially treated by conservative means such as NSAIDs, epidural injections, physiotherapy, and so on. But once patient suffers from severe neurological symptoms such as intermittent claudication or vesicorectal disorder because of the spinal stenosis, it leads the patients to experience surgical procedures. There is no uniform agreement among surgeons about the optimal treatment. But our experience along with several high-quality studies indicate that surgery provides better clinical outcome for degenerative spondylolisthesis and that fusion provides better outcome than decompression alone.

A prospective study was designed over 82 patients who had degenerative lumbar spondylolisthesis with severe neurological symptoms. The study time was from January 2003 to July 2014 in NITOR and BSOH, Dhaka. We selected the patients for surgery depending on two major following criteria: (1) The patient has clinically important and significant pain or neurological symptoms. (2) The patient has not shown sufficient clinical improvement despite conservative care at least for 3 months. We tried to manage those having significant osteoporosis and infection through conservative treatment despite fulfilling the aforementioned criteria. Our choice of surgery was TLIF for each patient. The steps included laminectomy, insertion of cage in the disc space, interbody strut bone graft surrounding the cage, and posterolateral bone grafting with fixation of spine by transpedicular screws and rods. Total follow-up time was 11 years and the minimum time was 6 months. Evaluation was done comparing their pre- and postoperative states which included clinical evaluation, X-ray showing gradual fusion with special investigation including CT scan and MRI.

A total of 82 patients (51 females and 31 males) with an average age of 59 years (range, 41–76 years.) having degenerative lumbar spondylolisthesis with severe neurological symptoms met the inclusion criteria. Among the patients, 57 had osteoarthritis. Total follow-up time was 11 years and minimum 6 months. The potential side effects included bleeding, postoperative infection, nonunion, residual deformity with spinal stenosis, and malposition of screws and rods. The mean anterior slip was 26.1% (range, 0–50%) before surgery and 24.8% at the final follow-up. The longer was the duration of preoperative insult to the spinal cord, the slower was the rate of recovery. According to these, the excellent outcome was seen in 69 patients (84% of cases), fair result was seen in 4 (5%), good in 5 (6%), and poor result in 4 (5%) cases. Nonunion after surgery was observed in three patients. Neurological symptoms improved in 1 month to 1 year. The Oswestry Disability Index Scores averages 11.1% (range, 0–62%) in at least 6 months' follow-up time.

Although surgical procedures cannot confirm lifelong recovery of the patients with symptoms, but does ensure a better and comfortable lifestyle with potential improvement of leg symptoms in case of degenerative spondylolisthesis. In spite successful fusion is achieved, better outcome will be ensured if any kind of activity that may overload the back is avoided.

The use of bone cement in orthopedic surgery has been quite current for many years. In spine surgery, it has been used first for replacing defects after corpectomy. Then, vertebroplasty and kyphoplasty got used worldwide. Sporadically, some surgeons used cement to refill the intervertebral space after discectomy, combined with dorsal stabilization and fusion. Most recently in our institution, we started to perform routinely percutaneous cement discoplasty, for elderly patients. We also use PMMA as a spacer in TLIF. In a previous retrospective analysis, we reviewed results with this kind of surgeries. The aim of this study was to validate the use of custom-made PMMA spacer in TLIF with a high level of evidence in a randomized, prospective study.

In our study, we planned to collect 100 consecutive patients to whom we perform one level TLIF in the lumbar spine. The patients are randomized in three groups by the GraphPad QuickCalcs software. Group A is standard TLIF with PEEK spacer positioned in the anterior part of the intervertebral space. Group B is standard TLIF with PMMA spacer placed in the anterior part of the intervertebral space. Group C is standard TLIF with PMMA spacer positioned in the posterior part of the intervertebral space. Patients between the age of 18 and 65 years were included. Patients with a high-grade spondylolisthesis, metabolic bone disease, spinal infection, cancer, and severe scoliosis (Cobb over 30 degrees) were excluded. We evaluate the clinical results with standard questioners. Radiological evaluation focuses on bony fusion, loosening of any instrument implanted (PMMA spacer or screws), osteolysis around the cement, subsidence, changes in segmental, and overall lordosis according to the position of the spacer.

Until today, 40 patients have a minimum of 1-year follow-up. We present these early results. On CT scan 6 months after surgery, we could observe completed fusion in 78.5% of the operated segments. The fusion rate was higher in the PMMA spacer groups (B + C), but the difference is not significant. We found six subsidence (15%), from four was in the PEEK spacer group (A) meaning, that the subsidence rate was significantly higher in this group. We found radiolucent zone around the implant (loosening) in only two cases (5%), one in the group A and one in group B. The overall clinical result was very good in 61%, good in 28%, and poor in 11% of the cases without significant difference between the groups.

With this preliminary results, we can estimate that the use of custom-made PMMA spacer in TLIF even in younger population provides good results noninferior to preformed PEEK spacer, and it even has some following advantages on preformed cages: (1) It fits better to irregularity of the end plates than preformed spacers, which can correlate with the difference in subsidence rate. (2) It requires smaller annular window to implant.

Surgical indications are not always clear cut and patients need to participate in the process of making an informed decision, weighing the potential risks, and benefits to have surgery or not. This decision is likely heavily influenced based on their pain level, work, and activity limitations. There is much information available on the outcomes and complications of surgery for lumbar disc herniation. The purpose of this study was to determine for which indications spine surgeons would have surgery themselves.

A survey was designed using Survey Monkey, which ensures responses are anonymous. The survey was sent to the ISASS surgeon membership. The survey collected basic demographics. The scenario for seeking treatment was that if you had sciatica with a 5 mm disc herniation identified on MRI and pain at the confirmed level, when would you consider some form of direct decompressive surgery? The second set of questions addressed if in the same circumstances and having failed nonoperative care, separately assessed pain level, work limitation level, and nonwork activity limitation level for which the surgeon would have spine surgery to treat the herniated disc.

There were 67 responses to the survey. The majority of those completing the survey were in the age ranges of 45 to 54 years (40.3%) and 55 to 64 years (35.8%). The most frequent response selected to the question about the number of years in practice was 21 to 30 years (43.3%). More than half selected one of the two categories indicating performing between 100 and 300 spine surgeries a year. The majority of responses came from members in the United States, but there were participants from Canada, Australia, Europe, and Asia. Responses to the question about having surgery for a 5 mm herniation indicated that 75.8% of surgeons would have surgery if they had buttock and leg pain below the knee that limited work activities 2 of 5 days so that on those 2 days you had to stop after half day of work. Less than 20% would have surgery if symptoms interfered with nonwork activities, but not work. Of note, 18.2% indicated that they would not have surgery for the herniated disc regardless of the symptoms experienced. The second series of questions separately assessed pain, work, and nonwork activities. With respect to pain intensity, on a 0 to 10 scale, 63.6% would have surgery for scores of 7 to 10. With respect to work, 39.4% indicated they would have surgery if experiencing continual pain at work, 34.8% would have surgery if able to work only half days, and 19.7% would have surgery only if they were unable to work at all. Partial limitation of activities would lead 28.4% of respondents to have surgery, while 68.7% would have surgery if their activities were severely limited.

The results of this survey found that many spine surgeons would have surgery if the pain was 7 or greater on a scale of 10, they continually experienced pain during work or had severely limited activities. Interestingly, 18.2% indicated they would not have surgery regardless of symptoms.

Back pain is an important socioeconomic problem, and the results of the surgical management of lumbar degenerative disorders have a wide variation throughout the literature, possibly because of the several factors affecting pain level and perception in this group of patients. This study aims to evaluate the influence of nonorganic signs on the outcomes of lumbar fusion for degenerative pathologies. The secondary aim is to evaluate the capacity of physicians to identify patients at risk for poor results secondary to nonorganic signs.

Material and Method: Prospective clinical study, with independent data collection and analysis pre- and postoperatively (6 months). Patient selection included those with indication for lumbar surgery secondary to lumbar degenerative pathology up to three levels, failure of conservative treatment for at least 6 months and capability to understand the questionnaires and the informed consent. Staff physicians evaluated patients subjectively regarding the presence of depressive and/or nonorganic signs; if the physician suspected that the patient had signs of depression or nonorganic signs, the patient would be excluded from the study. Overall, 60 patients were followed with DRAM, Zung, Oswestry disability questionnaire, presence of nonorganic signs, and VAS pre- and postoperatively. Data regarding spine pathology and patient's medical history were also collected.

There were no significant differences regarding pain levels and surgical results between patients with (n = 26) and without (n = 30) nonorganic signs. The same happened with high (50% of the patients) and low scores using the DRAM and Zung evaluation of depressive symptoms.

Although results were similar in the subset of patients, this study showed that subjective analysis was not able to correctly identify patients with risk factors for depression, and that the application of specific questionnaires such as the ones in this study help to improve patient selection for lumbar spine procedures.

Degenerative spinal changes are often accompanied by osteoporosis in elderly patients. In these cases, traditional interbody devices can strongly subside into the irregular deformed end plates and vertebrae during or after the surgical stabilization. To avoid implant subsidence, a new technique is developed where PMMA bone cement is applied as interbody device providing better contact and even more load transfer along the vertebra–implant interface. In this study, the results of in vitro mechanical compression tests are presented comparing a traditional PEEK spacer and the new PMMA cement spacer.

Overall, 22 human cadaveric lumbar segments were prepared and included in the final analysis (group C: cement; N = 12, group S: spacer; N = 10). Preparation included the following: (1) isolation of a human cadaveric lumbar segment, (2) parallel embedding of cranial and caudal free end plates, (3) CT scanning before applying interbody device, (4) introducing either a D-shaped PEEK spacer (Sanatmetal) or a custom-made PMMA (Cemex) spacer as interbody device, (5) CT scanning after applying interbody device, (6) performing uniaxial compression tests (Instron 8872), and (7) CT scanning after the compression test. Measurement of geometrical parameters and bone mineral density were performed on CT images.

Comparison of geometry and BMD of “C” and “S” groups showed no significant difference, specimens were selected for the two groups to be as similar as possible. Failure load was also similar (group C mean: 1,929 N, 95% CI: 1,732–2,126 N; group S mean: 1,914 N, 95% CI: 1,316–2,512 N), although standard deviation was higher in the PEEK spacer group (group C SD: 309 N; group “S” 836 N). Stiffness was significantly higher in the PMMA cement group (group C mean: 1,144 N/mm, 95% CI: 913–1,375 N/mm, SD: 363 N/mm; Group S mean: 525 N/mm, 95% CI: 396–654 N/mm, SD: 180 N/mm). Implant subsidence was significantly smaller in the PMMA cement group (Group C mean: 3,525 N/mm, 95% CI: 2.81–4.24 mm and group S mean: 5.64 N/mm, 95% CI: 4.89–6.39 mm). There was another important difference between groups in the relationship of failure load and BMD. In group S, the BMD correlated strongly with failure load (R₂ = 0.53), while in group C, there was no correlation (R₂ = 0.0019).

Analysis of mechanical test results showed that using PMMA cement spacer compared with PEEK spacer yields a significantly stiffer construct with smaller subsidence, although loads that cause irreversible mechanical failure of the segments are similar. In the case of PEEK spacer, the failure load depends greatly on bone quality, whereas in the case of PMMA cement spacer such correlation was not observed, as PMMA can penetrate into the irregular osteoporotic bone yielding a massive vertebra–implant interface. From these results, we can conclude that the use of PMMA cement spacer may be mechanically superior to traditional PEEK spacer in the elderly population.

The authors gratefully acknowledge the Hungarian Scientific Research Fund OTKA for providing financial support in the frame of the grant K-075018.

There have been a limited number of small case series reporting improvement in patients' function and pain scores following removal of pedicle screw metalwork for nontraumatic lumbar fusion surgery. The investigators' aim was to determine the degree of satisfaction from a patient cohort; and improvement in pain status after removal of pedicle screw instrumentation and factors that may influence the outcome.

Patients who had removal of pedicle screw instrumentation for posterolateral lumbar fusion in the preceding 2 years were identified from the database of a single spinal surgeon's case series. All patients completed pre- and postoperative Oswestry Low Back Pain Disability Questionnaire (ODI). Patient inclusion criteria were persistent axial low back pain imaging confirmed solid fusion, nonradicular symptoms and no other cause found for pain, for example, infection. Exclusion criteria included exchange of metal work, revision fusion, or other additional therapeutic procedures. Following removal of metal work via previous incisions, all patients had debridement of fibromuscular tissue and adhesiolysis, thorough saline lavage, and local bone grafting to the site of metal removal.

A total of 21 patients were identified from the database with a mean follow-up of 14 months (range, 3–24 months). There were two postoperative hematomas requiring aspiration but no additional complications such infections, reoperations, or deterioration of neurological deficits. The former two patients did not record improvement in VAS and both were neutral in satisfaction. Treatment success as assessed from the ODI analysis was rated as excellent in 6 of 21, good in 7 of 21, fair in 5 of 21, and poor in 2 of 21. Reduced class II opioids, benzodiazepines, or neuromodulator use was reduced in 7of 21, no different in 11of 21, and increased in 3 of 21. The proportion of patients with an improvement in VAS was 13 of 21 (62%) with an improvement of at least 2 or more being (43%) 9 of 21 of patients surveyed. The visual analog scores were the only component of the ODI able to be assessed for all of the patients with mean scores of 5.9 preoperatively to 4.2 postoperatively (p = 0.04). The proportion of patients with an improvement in VAS was 13 of 21 (62%) with an improvement of 2 or more being 9 of 21 (43%) of patients surveyed. Patients who did not receive analgesic benefit and/or had lower satisfaction from the removal of instrumentation procedure tended to be male, compensable, had experienced more years of symptoms, shorter times to metal wear removal, and an increased prevalence of preoperative class II opioid requirements. There was, however, no trend to a difference with regards to number or location of levels fused, number of procedures, presence of pseudoarthrosis or broken/loose metal wear and method of preoperative fusion confirmation. Of the 21 patients, 14 (67%) patients indicated that they would undergo the same treatment again given their experience and outcome.

In our series, removal of pedicle screw implants in individuals with ongoing low back pain following solid fusion lead to good or excellent results in two-third of patients and did not lead to any adverse effects and/or complications.

Patients with lumbar spinal stenosis who do not respond satisfactorily to nonoperative measures may require decompression. Laminectomies/decompression without instrumentation may cause instability and associated symptoms. Fusion often involves multiple segments potentially increasing the risk of proximal junctional kyphosis (PJK), adjacent segment disease (ASD), and surgical morbidity of lateral exposure to prepare fusion bed. We have therefore been using the TRANSITION Stabilization System (Globus Medical, Inc., Audubon, Pennsylvania, United States) to provide stability without fusion at the operated levels. Following insertion of pedicle screws, to which the rod is attached, a semirigid rod is custom built along a central cord using a combination of rigid screw head attachments, flexible spacers, and a compressible bumper. Biomechanical studies have indicated superior performance to other similar systems. We report our clinical results.

A retrospective analysis of prospectively collected data was performed for patients who underwent surgery between September 2011 and December 2013. Outcome measures included Oswestry Disability Index (ODI), Visual Analog Scale (VAS) back/leg pain, Hospital Anxiety and Depression Scale, and complications. Statistical analysis was performed with paired and unpaired tests.

Demographics: Data were available for 24 patients; 8 females and 16 males. Mean age at surgery was 66.8 years. Mean body mass index was 30.4 kg/m². Mean length of follow-up was 44 (range, 10–109) weeks. Mean postoperative length of stay was 7.2 days, and when those patients requiring reoperation for complications were excluded it was 4.4 days. Surgery: A total of 10 L3–S1, 4 L4–S1, 1 L4–L5, 3 L2–L5, 4 L3–L5, 1 L1–L5, and 1 L2–S1 stabilizations were performed with a variety of combined central and foraminal decompressions. Mean blood loss was 648 mL and surgical time 176 minutes. Eight patients sustained intraoperative dural tears that were sealed with fibrin sealant. Outcomes: Mean ODI improved from 45.1 to 31.3 (p = 0.001), VAS back from 6.7 to 3.7 (p ≤ 0.01), VAS legs from 6.7 to 2 (p ≤ 0.01), anxiety from 6.1 to 5.4 (p = 0.37), and depression from 7.3 to 3.7 (p = 0.033). There was no statistical correlation between pre- and postoperative ODI, VAS back or legs, depression/anxiety scores, and demographics. Reoperations: There were three early reoperations: one patient for discharging wound with positive microbiology and for revision of a screw, one patient for discharging wound with negative microbiology, and one patient for revision of a screw. There were no implant failures or revisions for PJK or ASD to date.

Our results using the TRANSITION Stabilization System suggests that pedicle-based semirigid posterior stabilization systems warrant further consideration as a potential tool in providing satisfactory early postoperative results while potentially reducing the long-term morbidity associated with fusions for lumbar stenosis. We would encourage further research to assess longer term results and radiographic outcomes.

There is much literature addressing back pain and pregnancy, often attributing the pain to changing loads and stresses on the spine. There is much less information available on pregnancy after lumbar spinal surgery. Many women considering surgery or who have undergone surgery are of child-bearing age. They may have concerns about the safety of pregnancy after surgery. This may be particularly true of procedures performed through an anterior approach, such as lumbar total disc replacement (TDR). The purpose of this study was to evaluate the course of back pain and safety of pregnancy after lumbar TDR.

From a single center, 18 patients were identified who became pregnant after lumbar TDR surgery. Data were recorded from clinic records and mailed questionnaires. Questionnaire data were collected for 15 of 18 patients, although not all patients responded to all questions. For the remaining three patients, as much data as possible were collected from charts. The mean patient age at the time of surgery was 28.2 years, ranging from 25 to 35 years. The majority of patients (77.8%) had a single level operation with L5–S1 being the most common.

Information related to back pain during pregnancy was available for 16 patients. Eight (50%) reported no increase in back pain during pregnancy, while the remaining eight did report increased back pain. Among the eight patients with increased back pain, it resolved postdelivery in all but one. There were no pregnancy-related complications. The mean time from surgery to delivery was 38.7 months (range, 9–102 months). Of the 15 patients for whom delivery method information was available, 10 (66.7%) had caesarian delivery while 5 (33.3%) had vaginal delivery. Of the 15 patients, 13 carried to term. The remaining two patients delivered twins prematurely. The mean birth weight was 7.4 pounds with the exception of the two sets of twins who had a mean weight of 4.4 pounds (range, 3.9–4.9 pounds). Three patients experienced two pregnancies post-TDR. Data for the first pregnancy are included earlier. In all the three patients, the second pregnancy was carried to term; one had a cesarean delivery, and the other two had vaginal delivery. One of the three had increased back pain during pregnancy which resolved after delivery.

Although based on a small patient sample, this study found that pregnancy after lumbar TDR surgery followed a typical course with no spine-related complications. The percentage of women delivering via cesarean delivery was greater than the 32.8% reported in the Center for Disease Control and Prevention's National Center for Health Statistics for 2012. It is hoped that this study may provide reassurance to women who were pregnant after TDR surgery that they should not be unduly concern about the safety of pregnancy and delivery because of their spine surgery.

Decompressive surgery for symptomatic lumbar spinal stenosis is associated with good outcomes provided that appropriate patient selection is undertaken, which has proven critical (Aalto et al 2006). It has previously been proposed that the MRI appearance of multifidus is correlated to leg and back pain symptoms (Ali et al 2011 and Kader et al 2000). Therefore, our aim was to assess whether the preoperative MRI appearance of multifidus was predictive of outcomes for lumbar spinal stenosis surgery and could be used in patient selection. Our hypothesis was that patients with fatty atrophy on MRI would have significantly poorer clinical outcomes than those without.

A review of patients who had undergone lumbar spinal stenosis surgery in the previous 2 years (minimum 1-year follow-up) and had completed spine tango outcomes was undertaken. Exclusion criteria were additional procedures, for example, fusion and patients without MRI scans. Individual patient comorbidities and complication profiles were also assessed. The multifidus caliber was measured for each patient on MRI using a DICOM viewer by two assessors blinded to the outcome scores. In addition to the Kader et al (2000) classification, elliptical cross-sectional area mapping of multifidus was taken as an average measurement at the axial L4/5 level. Also, measured were the posterior adipose tissue layer and dimensions of the L5 vertebral body, areas of critical stenosis and psoas muscles, respectively.

A total of 66 patients (41 females and 25 males) met the inclusion criteria and underwent analysis. There was a significant improvement for the cohort in ODI and COMI scores following surgical intervention and 89% of patients had improvement in ODI and COMI scores. The mean age was 67 years (range, 29–86 years). Overall, 44 patients had single level decompressions while for 2 level and 3 level decompressions; there were 16 and 6 patients, respectively. Overall, 44 (84%) of single levels involved either L4/5 or L5/S1 (37/44) with L3/4 and L2/3 involved in five and two patients, respectively. Moderate or severe fatty degenerative changes (Kader grades II or III) were noted in 71% of patients while a mean CSA (cm²) of 8.4 cm² or less for multifidus at the measured level was noted in 71% of patients. The proportions of the cohort who improved more than 40% in their COMI and ODI when comparing the cohorts of patients with CSA < 8.5 cm² compared with ≥ 8.5 cm² were significantly different (47 vs. 79% [p = 0.02] and 32 vs. 68% [p = 0.006]). For patients with a Kader grade of 0 to 2 and CSA ≥ 8.5 cm², there was significantly more percentage improvement with ODI/COMI (mean 84, 75) compared with Kader 2 to 3 and CSA < 8.5 cm² (mean 28, 23) (p = 0.05).

The appearance of lumbar multifidus on preoperative MRI is predictive of outcomes of lumbar spinal stenosis surgery with better results at a minimum of 1 year in patients with less fatty degenerative changes and higher cross-sectional area. This has implications for use in the perioperative setting and further research on the value of preoperative imaging for other spinal surgery is indicated.

Surgical decompression is the gold standard in the treatment of symptomatic lumbar spinal canal stenosis (LSCS) without clinically significant instability. With the advent of microsurgical techniques and better accessories such as the tubular retractor system (TRS), unilateral approach bilateral decompression (UABD) has been advocated as the decompressive technique of choice because of the preservation of anatomically important stabilizing structures. This retrospective study evaluates the midterm results of UABD performed with and without the TRS in a regional hospital.

From April 2008 till November 2013, 89 patients with symptomatic LSCS without clinical instability had UABD performed. On the basis of the surgeons' preference, 56 cases were operated with the TRS employed. The mean follow-up was 30.8 months. Clinical outcomes were evaluated by the Visual Analogue Scale (VAS), Japanese Orthopaedic Association lumbar spine score (JOA score), Oswestry Disability Index (ODI), and Roland Morris Disability Quotient (RMDQ). Complications, rate of reoperation, and patient's subjective satisfaction were also evaluated.

A total of 150 levels were decompressed (average, 1.7 levels per patient). The average operation time and blood loss per level was 99.4 minutes and 67.9 mL, respectively. The mean postoperative hospital stay was 4.5 days. The average leg VAS, JOA score, ODI, and RMDQ improved from 7.1, 15.5, 48.3% and 13.1 to 3.3, 22.1, 35.4% and 11.5, respectively, at final follow-up. The subjective satisfaction was 64%. Given the choice, 92% of these patients would choose to have the same procedure again. There were no statistical significant difference between the TRS and no TRS group in age; sex; side of approach; the preoperative, postoperative, and improvement in leg VAS, JOA score, ODI, and RMDQ; follow-up duration; operation time; and subjective satisfaction. Blood loss (67 vs. 178.4 mL, p = 0.09) and postoperation hospital stay (3.9 vs. 5.7 days, p = 0.003) were both in favor of the TRS. Overall, five incidental durotomies in the TRS group (8.9%) and 3 (9%) in non-TRS group were registered, giving rise to a total 9% of the incidental durotomy rate. All of these eight cases were treated conservatively and none of them needed any further procedures as a remedy. Otherwise, no remarkable perioperative morbidities had been recorded. Within the evaluation period, two cases from the TRS group need re-decompression with instrumented fusion because of symptomatic recurrence, equivalent to an overall 2.2% reoperation rate.

Microsurgical UABD generates satisfactory clinical outcomes in selected patients with symptomatic LSCS without clinical instability. No apparent clinical benefit was found in employing the TRS other than an average 1.8 day short postoperative hospital stay.

Lumbar disc herniation is one of the major factors leading to lumbar radiculopathy. Both operative and nonoperative treatments have been shown to be effective in treating patients with lumbar herniated disc and radiculopathy. Even though both approaches can provide a rapid improvement, there are potential adverse events and rising costs associated with both, surgical and nonsurgical procedures. The aim of our study was to better understand the procedural trends, cost, and re-operative incidence in patients with lumbar herniated discs and radiculopathy.

Patients with lumbar herniated disc and radiculopathy from 2007 to 2010 were identified in the United healthcare database using ICD-9 and CPT codes. Treatment procedure were recorded and classified in the following three groups: surgical group, including discectomy, microdiscectomy, and endoscopic direct visualization discectomy procedures; minimally invasive group, including endoscopic assistance indirect visualization discectomy, intervertebral chemonucleolysis, and disc aspiration; and nonsurgical group, including bed rest, analgesics, nonsteroidal anti-inflammatory drugs, exercise, physical therapy, or epidural steroid injection. Data were collected and analyzed based on the patient age (< 40, 40–65, and > 65 years) and regional distribution (Midwest, Northeast, South, and West).

A total of 162,682 patients were diagnosed with lumbar disc herniation with sciatica. There were 10,183 patients within the surgical group, 235 in the minimally invasive group, and 152,337 patients in nonsurgical group. There was a significant difference in procedure type based on the age and region. In < 40 years of age subgroup, there was an increase in the operation rates, 5.99, 6.15, 6.32, and 6.51%, from 2007 through 2010. The operation rates decreased with age, 6.95% (< 40 years), 5.65% (40–65 years), and 4.28% in > 65 years group. On the other hand, number of nonsurgical procedures increased with age and was 92.57, 93.99, and 95.32%, respectively. Surgical rates were the highest in the West region (7.58%) and the lowest in the Northeast (3.67%). Nonsurgical procedures had the opposite trends with the Northeast (96.18%) having the highest and West (92.31%) the lowest rate.

There was a difference in the operation rate based on the age and region distribution, with the subgroup < 40 years having the highest operation rate and the > 65 years of age subgroup having the lowest operation rate. The West region has the highest and the Northeast region has the lowest operational rate. Within the nonsurgical group, we observed opposite trends. Our next steps include cost analyzes and defining the surgical likelihood of patient having nonoperative procedures.

Adjacent segment degeneration or disease (ASD or ASDs) has been one of the most concerned issues after fusion of the lumbar spine. To investigate the radiographical and clinical outcome of adjacent segment degeneration after topping-off (posterior lumbar interbody fusion + above segment interspinous implant) procedure, a retrospective study was conducted.

All lumbar spinal stenosis cases from the department of orthopedics of Beijing Chaoyang hospital that received PLIF + above segment Coflex between August 2008 and October 2012 were analyzed retrospectively. Analysis the gender, age, body mass index of all the patients was done. The X-ray films before and after surgery were measured and got some data (total lordosis, the height of disc, range of motion, lordosis, and olithesis). One-year follow-up were examined by MRI, observed the degeneration of intervertebral disc. All data used SPSS 12.0 for analysis.

There were 32 patients in topping-off (males 21 and females 11), including (L4/5 PLIF + L5–S1 Coflex) 12 patients in group 1 and (L3/4 PLIF +  L4/5 Coflex) 20 patients in group 2. Age averaged 61.5 years (range, 30–79 years) and follow-up averaged 24.6 months (range, 14–63 months). The average surgery time was 110 ± 21 minutes. The average blood loss was 401 ± 110 mL. Postoperation the ODI, JOA, and VAS score improved. There was no significant difference in the height of disc of the Coflex segment and above segment between before and after surgery. Segmental lordosis of Coflex and total lordosis were all increased significantly (t = −1.9 and −2.0, p < 0.05). There was no significant difference in the number of the disc change of Modic grade of end plate (p > 0.05).

Topping-off surgery is fit for the patients who have serious stenosis of lumbar spinal cord with mild and moderate stenosis of adjacent segment, which can restrict the adjacent segment's range of motion and prevent excessive olisthesis of adjacent segment in both extension and flexion, also can sustain the height of Coflex segment. It shows a good result after short-term follow-up. Topping-off surgery plays an active role in preventing the adjacent segmental degeneration.

Lumbar disc herniation has been recognized as an important cause of low back pain. Intervertebral disc prolapse occurs predominately in L4–L5 and L5–S1 level. It includes three stages mainly protrusion, extrusion, and sequestration. Results of operative treatment for disc lesion vary depending on the level of lesion and duration of symptoms, this study aims to assess the outcome of discectomy in the different stages of disc lesion.

A prospective study was done in 40 patients diagnosed with lumbar intervertebral disc prolapse. Demographic data, history, clinical examination, and details of investigations and intervention in the form of open lumbar discectomy/fenestration were recorded in the study proforma. Clinical follow-up was done at 2 weeks, 3 months, 6 months, and 1 year intervals regarding pain, disability, and the functional outcome were evaluated with VAS, Modified ODI score, and SF-36 questionnaire.

In our series of 40 patients, 8 (20%) were in 21 to 30 years, 18 (45%) in 31 to 40 years, 5 (12.5%) in 41 to 50 years, 8 (20%) in 51 to 60 years, 1 (2.5%) in 61 to 70 years age groups. Overall, 47.5% of patients had disc protrusion, 40% had extrusion, and 12.5% had sequestration. Overall, 60% were males and 40% were females. Overall, 75% of patients had L4–L5 disc lesion, 12.5% had L5–S1 lesion, 10% had both L4–L5, L5–S1 lesion, and 2.5% had L3–L4 lesion. Fenestration was done in 82.5% patients and laminectomy done in 17.5%. Postoperatively, neurological deficits and SLRT improved. There were statistically significant reduction of pain, improvement in disability, and a better functional outcome at the end of 1 year as assessed by VAS, modified ODI score, and SF-36 questionnaire in all the three stages of disc lesion; however, the improvement was better in stage 1 and stage 2 compared with stage 3. Complications included superficial wound infection, neurological deficit, and failed back syndrome.

Open lumbar discectomy by fenestration/laminectomy is a safe, effective and reliable surgical procedure in all stages of intervertebral disc prolapse, the outcome is better in stage 1 and stage 2 lesions than in stage 3 lesions.

Management of tuberculosis spine still possesses many challenges. Availability of antitubercular drugs has changed the outcome. However, present recommendation by the WHO of Directly Observed Treatment Short course (DOTS) has sound scientific basis, but the optimum duration is still controversial. We conducted a prospective study on a consecutive series of patients with spinal tuberculosis treated with Category I Revised National Tuberculosis Control Program (RNTCP) regime based on DOTS strategy from January 2011 to June 2014 to evaluate the efficacy and to come to a conclusion regarding optimum duration of treatment.

A prospective study of 60 consecutive patients of spinal tuberculosis treated with Category I RNTCP based on DOTS strategy. All the patients were followed for a minimum of 1 year. Surgical intervention was done in patients presenting with significant neurological deficits. Patients diagnosed clinicoradiologically and histopathologically (n = 8) were enrolled in the study. The outcome was graded into excellent, good, fair, and poor based on clinical, laboratory including return of ESR to normal and correction of lymphocytosis and radiological like a return to normal bone density and sclerosis, bony ankylosis, and disappearance of marrow edema on MRI.

In 60 cases, 63.4% (n = 34) males and 36.7% (n = 26) females. Overall, 10% (n = 6) were with predestructive lesion, 53.3% (n = 32) were in the early destructive phase, 30% (n = 18) with mild angular kyphosis and 6.67% (n = 4) with moderate angular kyphosis. Outcome of our study were excellent in 46.67% (n = 28), good in 36.67% (n = 22), fair in 10% (n = 6), and poor in 6.67% (n = 4). Duration to cure spinal tuberculosis 6 months 30% (n = 18), 9 months 56.67% (n = 34), and 12 months 13.33% (n = 8).

The duration of treatment for cure of spinal tuberculosis was 100% (n = 6) in predestructive and 37.5% (n = 12) in early destructive phases was 6 months, 62.5% (n = 20) early destructive, and 77.76% (n = 14) mild kyphotic phases were 9 months and 22.2% (n = 4) mild destructive and 100% (n = 4) moderate kyphotic phases was 12 months. Favorable outcome and short duration of chemotherapy is needed in patients treated early.

This study aims to evaluate and compare the outcomes of two antitubercular chemotherapy regimen prescribed for 9 months (group A) and 12 months (group B) on patients with Potts spine without neurological deficit.

A prospective study in which 59 patients were included, who were prescribed either of the regimes. The outcome measures were noted immediately after the completion of the treatment, at 6 and 12 months. The variables were evaluated on the basis of clinical, hematological, and radiological criteria, which included pain, Hb, ESR, CRP, and kyphotic angle. A mixed model ANOVA was used to compare group A and group B across different times of assessment (0, 6, and 12 months posttreatment) for each variable separately. The level of significance was p < 0.05. Also, the differences from baseline at 6 and 12 months were compared across groups. As the data were not normally distributed, Mann Whitney U test was used. The p value was adjusted for multiple comparisons to be less than 0.05/2 or 0.025.

Both the groups were demographically comparable. Pain (ODI) was found to be improved in both the groups, but on comparison 12-month regime was found to have reduced pain scores than 9-month regime during 6-month follow-up (ODI: group A 19.2 and group B 17.3) but in the 12-month follow-up showed no statistical difference in pain score (ODI: group A 13.9 and group B 12.6). There was no neurological deterioration in both groups. CRP improved in both the groups (group A 7.31 and group B 7.03) and no statistical significant difference was found between the two regimes. There was an increment in Hb levels and kyphotic angle in both the groups, but the comparison could not be drawn between the two groups for both the variables as baseline values were not comparable whereas ESR reduced in both the groups but because of the significant difference at baseline, none of the groups could be compared. To make the groups comparable, a nonparametric analysis was used which showed a statistically significant deterioration of kyphotic angle in group A (0.6 degree) than in group B (0.2 degree) at the end of 1-year follow-up, but it was not found to be significant clinically. Also, statistically significant results were obtained for Pain scores with better improvement of pain with –group A than group B (group A 14 and group B 10) but again the improvement was clinically nonsignificant.

After 1-year follow-up of patients who had completed their antitubercular treatment, we can conclude that there was no additional benefit of prescribing antitubercular therapy for 12 months over 9 months in patients of Potts spine (1 or 2 level) without any neurological deficit. Long-term follow-up is needed to further establish the advantage of 9-month regime over 12-month regime.

Tuberculosis is the leading cause of death in third world countries, from a single infectious disease. It paralyses the society when it affects the spine because of its resultant neurological deficit in the form of quadriplegia, paraplegia, loss of bladder and bowel control, bed sores, and continuous financial burden on family and whole society. Early spinal decompression and stabilization with standalone cage have dramatic results in terms of improvement in neurology, relief of pain, and correction of deformity. The objective of the study is to determine outcome of anterior decompression and stabilization with locally made standalone cage and bone graft in caries spine in terms of improvement of neurology, relief of pain, and improvement of kyphotic angle.

It is a prospective case series study including 850 cases who were treated at GTTH from 2003 to 2010. After preoperative assessment of pain, neurology, and measurement of angle of deformity, all patients were treated with anterior decompression and then stabilization was achieved with bone graft and standalone locally made cage. After surgery, patients were followed at 6 weeks, 3 months, 6 months, and 1 year to assess neurology, relief of pain, and kyphotic angle.

Neurology improved in 92% of patients, pain relieved in 95% of cases, and there was mean correction of 18 degrees in kyphotic angle at the end of 1-year follow-up.

Early diagnosis and early intervention give excellent results. After anterior decompression, stabilization with cage and bone graft results in significant improvement of neurology, relief of pain, and correction of kyphotic deformity. There is no need for added instrumentation.

Tuberculosis of spine being an anterior disease, anterior decompression, and fixation has been long considered as the gold standard. Recently, the posterior approach surgery has gained popularity, based on the principle of adequate debridement and stable fixation with much lower complication rates. This retrospective study aims at evaluating the role of a posterior stabilization with transpedicular posterior alone decompression for tuberculosis of spine.

A total of 55 patients surgically treated with posterior pedicle screw fixation and transpedicular decompression along with chemotherapy for tuberculosis of spine between January 2009 and May 2013 and had a minimum of 12 months' follow-up were included in the study. Their functional outcome (VAS score), neurological outcome (ASIA grading) and radiological outcome (X-ray and MRI) were assessed. Patients with kyphotic angle > 30 degrees, more than three contiguous discal involvement and multifocal lesions were excluded from the study.

Mean age of patients was 47.2 years. Thoracic spine was involved in 29, thoracolumbar in 16, and lumbar in 10 patients. Mean follow-up was of 23.2 months. Most common indication for surgery was instability pain. VAS score improved from an average of 9.2 to 2.4 in postoperative period and 3.2 at follow-up. Neurological improvement was seen in all patients with neurological deficits preoperatively. Mean kyphosis angle was 20.6 ± 4.8 degrees and was corrected postoperatively to 7.4 ± 3.2 degrees (> 50%). At the latest follow-up, there was a mean loss of correction of 3.1 degrees resulting in 6.1 degrees of final correction. Bony fusion was achieved in 73% patients with no patient having any clinical signs of pseudoarthrosis.

Posterior stabilization and transpedicular decompression have shown an improvement in the functional outcome and the neurological status in most of the patients without the need of an anterior decompression and fusion. Good maintenance of spinal alignment and fusion along with resolution of the inflammatory process on MRI can be satisfactorily attained through posterior stabilization and transpedicular decompression when accompanied by chemotherapy. However, further follow-up is necessary to monitor for possible disease recurrence or implant failure.

Surgical outcome, complications, and safety/efficacy of various types of surgery in active dorsal spine tuberculosis with myelopathy have been extensively studied. The objective of this study is to find out the prognostic factors that determine neurological recovery including onset and progression of pain/neurological deficit, spinal cord level involved, type of material compressing the cord, (pus/granulation tissue/caseous material). The time frame required for postoperative recovery in motor, sensory, and bladder functions were also studied.

A total of 21 patients, with strict inclusion criteria were recruited from January to December 2010 were studied prospectively. In preoperative assessment, onset and progression of pain and neurological deficits and level of affection were noted. On the basis of ASIA classification, we have classified our patients by considering the predominant MRC grade in more than half of key muscles below the level of lesion as the motor function grade. For sensory assessment, we classified sensory loss into the following four categories: (1) when there is a complete loss, (2) when posterior column sensations were present but anterior column was lost, (3) when both anterior and posterior column sensations were impaired, and (4) when normal. Bladder dysfunction was scored using JOA score for bladder dysfunction. All patients underwent spinal stabilization and transpedicular/extracavitary decompression with posterior spinal fusion. During surgery, the nature of the compressing tissue (pus/granulation tissue/caseous material) was noted. Assessments were done at 48 hours, 7 days, 1 month, 3 months, 6 months, 1 year, and 2 years.

Duration from onset of pain to diagnosis, 4 months; from onset of pain to onset of neurology, 3.7 months; from onset of neurology to surgery, 1.39 months. Nine had acute neurological deterioration. Average preoperative motor grade was 2.05 which improved postoperative 48 hours, 2.90; 7 days, 3.38; 1 month, 3.76; 3 months, 4.33; and 1 year, 4.76. Overall 14 of 18 (77.8%) improved 1 grade within 48 hours. Everyone regained normal sensation by 1 month. At 3 months 7of 8 (87.5%) with preoperative catheter were out of it. The average preoperative power was 1.83, granulation; 1.67, caseous material; and 2.83, pus group, at 48 hours post-op; they improved to 2.5 (p = 0.0873), 2.55 (p = 0.101), 3.83 (p = 0.054), respectively. Lesion above D9 deteriorated from normal power to motor grade of 1.67 (mean) in 1.04 months, whereas, those below D9 took 1.86 months to deteriorate to 2.55 (mean). Postoperatively, above D9 improved to 2.41 in 48 hours, 2.83 in 7 days; and below D9 improved to 3.55 in 48 hours, and 4.11 in 7 days. Those who had sudden onset neurological deterioration showed improvement of 20% (p = 0.0014) motor and 37% (p = 0.0002) sensory in 48 hours when compared with slow deterioration, who showed 12.5% (p = 0.005) in motor and 11.33% (p = 0.085) sensory.

Sudden onset severe preoperative neurological deterioration is associated with faster postoperative recovery. Lesions above D9 show rapid onset and dense neurology with poorer surgical outcome. Compressing material does not influence recovery. 80% show motor recovery 1 grade,7 days; 2 to 3 grades, 3 months; 4 grades, 1 year. Complete sensory recovery, 1 month and 80% out of catheter, 3 months.

The rate of hematogenous infections of the intervertebral disc is increasing as mostly elderly and immunocompromised patients are affected. Surgery is indicated if the disease is progressive with destruction of the local with instability and/or neurological impairment. Debridement of intervertebral abscess, decompression of the spinal canal, and stabilization of the segment is necessary. At the lumbar spine, the ventral approach allows a radical debridement of the abscess but is less suited for stabilization, especially, in cases with poor bone quality. Therefore, often a two-stage intervention with additional decompression and stabilization from posterior is performed. In this study, we report on the midterm to long-term outcome of a single stage strategy with debridement, cement-interposition, and stabilization from posterior for progressive, erosive spondylodiscitis.

In a retrospective, single center case series, patients were evaluated who were surgically treated for progressive, erosive spondylodiscitis. The single stage strategy consists of a lamino- and recessotomy for decompression, debridement of the disc space, and the affected bone through annulotomy, filling of the resulting defect with an antibiotic containing cement spacer and monosegmental to bisegmental stabilization with transpedicular screw fixation.

From 1997 to 2012, 62 patients (34 males, 28 females, mean age 70 years [range, 32–92 years]) were treated with this technique. Overall, 54 patients were available for a minimal follow-up of 1 year (mean FU, 23.2 months; six died in the first year, two lost). Overall, two patients required additional debridement from ventral for persisting infection in all other the infection was treated successfully with the posterior intervention alone. Mean operation time was 164 (range, 120–347) minutes, blood loss 812 (range, 100–2,500) mL, length of hospital stay 11.7 (range, 2–42) days. Overall, 2 patients died during initial hospitalization, 12 patients during follow-up; in 4 cases, the cause of death was unknown in the other cases not related to the infection. Of the 14 patients, 8 with neurological impairment recovered completely. Three other patients needed a second intervention during the initial hospital stay (one hematoma, one revision of a dural tear, and one decompression for foraminal cement leakage). Nine patients required a secondary intervention of the spine during the first year (three implant loosening/failure, two adjacent segment disease, two spondylodiscitis with a different germ, and two persisting infection with debridement of the psoas abscess from anterior).

The single stage strategy with debridement, cement-interposition, and stabilization from posterior is a valid option for the treatment of progressive, erosive spondylodiscitis of the lumbar spine. The complication rate is relatively low and the rate of persisting infection with 3.2% comparable with the results of two-stage procedures.

Tuberculosis of the spine is the most common and dangerous form of TB infection accounting 50 to 60% of osseous tuberculosis. Although uncommon, spinal TB still occurs even in both developed and developing countries. The diagnosis of spinal tuberculosis is difficult and it commonly presents at an advanced stage. Delay in establishing diagnosis and management cause spinal cord compression and spinal deformity. Patients mostly present with lower limb weakness, Gibbus, pain, palpable mass, and kyphotic deformity in long standing cases.

To evaluate the efficacy and clinical outcome of surgical treatment of spinal tuberculosis treated by different approaches consisting decompression surgery, autogenous bone grafting and anti-TB chemotherapy. Before that a strong evidence-based diagnosis must be established which can be done by clinical features, MT test, and MRI of spine. Because vertebral body collapse from TB may be misdiagnosed as compression fracture. A total of 582 patients who had tuberculosis of the cervical, thoracic, and lumbar spine with moderate-to-severe cord compression were studied. Variable degrees of neurological deficit with deformity were treated at NITOR and BSOH, Dhaka, in the period from January 2003 to July 2014. Anterolateral decompression and autogenous strut bone grafting with simultaneous fixation by screws and rods were done. Posterior decompression, posterior interbody, and posterolateral fusion by bone graft with stabilization by transpedicular screws and rods. Appropriate anti-TB drugs were given to all patients for 18 to 24 months. The postoperative follow-up period was 12 months (range, 3–21 months).

Overall, 427 (73.4%) cases with neurological deficits recovered totally or partially. No neurological improvement had occurred in 69 (11.9%) cases with paraplegia. Overall, 56 (9.6%) cases were lost from follow-up. X-ray showing bony fusion was achieved in all cases for mean of 6 months (range, 4–8 months). There was no recurrence. Seven (5.1%) cases developed bed sore postoperatively. Excellent result was seen in 70% cases, fair in 15%, good in 10%, and poor in 5% cases.

For patients with spinal tuberculosis anterior debridement, auto graft bone fusion, anterior or posterior fixation appears to be effective in arresting disease, correcting kyphotic deformity and maintaining correction until solid spinal fusion.

As a chronic condition, the degenerative disc disease is a significant health problem. Several factors, such as genetics, mechanical stress, inflammatory and biochemical changes, vascular aspects, as well as infection may initiate degenerative processes, most commonly affecting the nucleus pulposus. It has been proposed that disc degeneration might be initiated by possible long-lasting low-grade infection.

The aim of the study was to assess the incidence of bacterial infection in the lumbar intervertebral disc specimens obtained from patients with disc herniation. In a prospective study, 62 patients were included (49% women and 51% men, average age 56 years, range 22–83 years). No experience of previous invasive spinal diagnostic procedures was reported. Disc specimens from levels L1 to S1 were collected during discectomies and microbiologically tested on blood, thioglycolate, and nutrient agars. MRI and CT were used as diagnostic methods and comparison of microbiological results to clinical signs and imaging was done.

In included patients, affected discs were removed. All microbiological cultures of disc specimens remained sterile after 1 week. Clinically, no signs of discitis were observed. The absence of an acute infection was confirmed by routine laboratory tests. Although clinical signs corresponded well to the MRI and CT imaging results, no connection with microbiological tests was found.

The exact pathobiology of degenerative disc disease is unknown. According to some studies, intradiscal bacteria may initiate a low-grade infection, playing a role in intervertebral disc degeneration. Our observations do not support this fact. Microbiological samples remained sterile in all patients, meaning that intervertebral disc is a sterile environment and bacterial infection is unlikely the cause of degeneration. Positive disc cultures in other studies may have resulted from specimen contamination after disc removal. However, the hypothesis of disc infection cannot completely be excluded because of slow growing and special growth conditions requiring bacteria that were not tested in our study. The potential role of low-grade bacterial infection contributing to the pathogenesis of degenerative disc disease thus remains uncertain. The genesis of disc degeneration might originate in the immune system and repeated episodes of injury and reparation that could culminate to progressive tissue damage.

Drug therapy still remains the main stay in the treatment of TB spine. However, surgery is indicated in some patients. According to the MRC guidelines, radical ventral debridement, fusion, and the reconstruction of the spinal column remain the gold standard of surgical treatment for tuberculous spondylitis as popularized by Hodgson and his coworkers as the “Hong Kong” procedure. The lack of resources such as theater time, and the dual impact of HIV disease and TB pandemic led to the development of other surgical management techniques. Thus, the anterior debridement and anterior column reconstruction has evolved as a method of surgical intervention. The aim of this study is to report on the adequacy and outcome of patients treated with this surgical technique.

This is a retrospective study of 54 TB spine patients (25 males and 29 females) who had anterior decompression and interbody fusion over a 3-year period (from 2012 to 2014). The indications for surgery were essentially the same as for 360 degrees decompression and fusion. The average age of our patients was 38.6 years and the disease was thoracic in 49 cases and thoracolumbar in only 5 cases. Except for six cases of single vertebral body involvement, all of our cases have two contiguous vertebral bodies involvement and required a four-body fusion. In four cases, we used fibular strut graft, while the titanium mesh cage with a mixture of allograft and autograft (the cut rib) was used in majority of the cases. The mean follow-up period was 13 months (ranging from 6 to 30 months).

The average preoperative kyphosis was 30 degrees; this improved to an average of 21 degrees postoperatively but falls to 27 degrees on the last follow-up (overall 10% improvement in the kyphosis angle). The mean Frankel neurology grading at the last follow-up was D (improvement from B to E). No loosening or breakage of implants occurs and no graft/mesh displacement recorded.

Early results of the anterior decompression and interbody fusion indicates that the method is adequate and the outcome gratifying. We therefore conclude that the procedure is an effective and adequate surgical technique for treating TB spine, but with possible risk of major complications.

Deep wound infections are one of the most common and serious complications of spinal surgery. The impact of such infections on long-term outcomes is not well understood. The purpose of this study was to evaluate the functional status and satisfaction in patients who suffered a deep wound infection after undergoing lumbar arthrodesis for symptomatic degenerative disc disease.

The authors conducted a prospective study in 13 patients with a clinical and radiological diagnosis of symptomatic degenerative lumbar stenosis and instability; after undergoing decompression and instrumentation–augmented arthrodesis, the patients suffered a deep wound infection (infection group). A 3:1 (39 patients) matched cohort was selected for comparison (control group). All surgeries were performed during the same period and by a single surgeon. The postoperative infections were all treated in a similar manner and the instrumentation was not removed. Both groups were followed up and assessed with validated following outcome instruments: Numerical Rating Scale of pain, Oswestry Disability Index, 36-Item Short Form Health Survey, Beck Depression Inventory, and Hospital Anxiety and Depression Scale. Patient satisfaction was also determined.

The median follow-up duration was 22 months (range, 6–108 months). The mean patient age was 62 ± 10 years, and 59.6% of the patients were female. There was no significant difference between the groups in pain, functional disability, quality of life, or depression and anxiety. However, 53.8% of the patients with infection were not satisfied with the procedure at the final evaluation, compared with 15.4% of the patients without a deep wound infection (p = 0.003).

Patients with successfully treated postoperative deep wound infections do not have a difference in functional outcome compared with patients who underwent an identical operation but did not suffer a complicating infection. Patients who suffered an infection were more likely to be unsatisfied with the procedure than patients who did not.

Anterior debridement and fusion using bone graft or cage is an accepted way of treatment of spinal infections. This can be achieved either through anterior or posterior or two-stage (anterior then posterior) surgery. In last few years, several research works reported good results with use of single posterior surgical approach for treatment of spinal infections. Spinal column shortening may be used in spinal fractures, deformities, and tumors. Since 2004, posterolateral exposure for debridement of thoracic and lumbosacral spinal infections and limited spinal shortening for anterior spinal reconstruction have been used.

A total of 32 patients with spinal infections (10 patients with infection of the thoracic spine and 22 patients with infections of the lumbar spine) were treated by this technique. Patients included 20 males and 12 females with a mean age of 56.3 (range, 20–72) years. Overall, 10 patients had neurological compromise (two Frankel grade A, three Frankel grade B, three Frankel grade C, and two Frankel grade D). Patients are operated under general anesthesia in the prone position through a single posterior exposure. Posterior stabilization by transpedicular screw fixation is performed. A rod is inserted in one side (usually the right side) while the rod in the other side is not inserted to give space sufficient for laminectomy and debridement. For full exposure of the anterior aspect of the vertebral bodies in the thoracic spine, excision of the medial 5 cm of one or two ribs may be performed. In the lumbar spine, dissection around the vertebral body is not needed as retraction of the cauda equine usually gives good space sufficient for curettage of the disc and debridement of the infected tissues and the technique is posterior lumbar interbody fusion (PLIF). Infected material is curetted and the second rod is inserted. Reconstruction of the anterior column is achieved by limited spinal shortening while carefully observing the dura for kinking. Then, posterior fusion is performed using local bone graft obtained from the laminae and ribs.

Patients were followed up for a mean of 33 (range, 6–80) months. Causative organisms were TB in 20 patients, Staph aureus in 4 patients, salmonella typhi, 1 patient, brucella in 1 patient, and bacteriologic testing of intraoperative samples did not find germs in 6 patients. Operative time ranged between 100 and 190 (mean 135) minutes. Successful fusion was achieved in all patients 3 to 6 months postoperatively. Neurological recovery to Frankel grade E was obtained in all but four patients (three Frankel grade D and one Frankel grade B). Five complications were encountered; malpositioned pedicle screw, deep venous thrombosis (DVT), delayed wound healing, kyphosis progression, and temporary neurological deterioration. No active infection occurred till the end of follow-up.

Posterolateral debridement and anterior reconstruction by limited spinal shortening is an alternative method for surgical treatment of spinal infections. Advantages of this technique include a wide cancellous surface for bone healing, good stability, avoid the morbidity of bone graft harvesting, short operative time, and less morbidity.

Primary infection of spine disc is a pathology that we see more frequently, mainly because of the decompensated diabetes mellitus, and whose treatment is with antibiotics and limited physical activity for a long time.

Describe the outcome of surgical treatment of surgical debridement, culture/biopsy, and fusion with pedicle fixation in the same surgical procedure in a group of patients with intractable and/or clinical/radiographic instability with infectious discitis of thoracolumbar spine pain, trying to improve pain and functional limitation time.

A group of 15 adult patients from January 2010 to December 2013 with infectious discitis, detected with laboratory tests, imaging (X-ray, CT, and MRI) with a history of diabetes mellitus with thoracolumbar pain with various treatment regimens were studied with visual analog scale of 7 to 10/10, limited functional scale (Oswestry 70–80%), severe limitation of travel (within 100 m), to surgical debridement + culture/biopsy + pedicle fixation was performed and a clinical/radiographical follow-up of 6 months to 3 years.

A significant decrease in pain intensity (60% of the initial pain intensity in the visual analog scale) was found, achieving a progressive improvement in functional scale in a period of time average of 6 to 8 months without detecting recurrence of infection, nor have major complications or deaths registered in monitoring patients with clinical and radiographical stability during the follow-up.

In this study, the results encourage aggressive treatment with instrumentation to improve intractable cases of pain and/or instability to shorten the period of immobility and inactivity of patients.

Traumatic quadriplegia is one of most serious conditions of cervical spine trauma, in almost all cases where the spinal cord is transected there is instability in three columns of vertebral column. Thus, 360-degree fusion is needed.

A total of 12 patients with traumatic cervical spine fracture with transected spinal cord were operated only by anterior cervical fusion with anterior plating during the period from July 2011 to December 2013. Intraoperative cervical traction was done, 11 patients iliac bone graft was used after anterior decompression.

All cases were reduced adequately and posterior fusion was not done, only Philadelphia neck collar kept for 3 months. Time of surgery was reduced. Three months' follow-up showed that there was no recent obvious radiological instability. Hospital stay was reduced and consequently bed-ridden hospital acquired infections were reduced.

Anterior fusion in traumatic cervical fractures with transected spinal cord is time saving and suitable for patients with complete quadriplegia and if spinal shock is present. Provided that, it was reduced with intraoperative cervical traction. But long-term follow-up is necessary.

Spine classification systems have been used for years to create a universal language for describing injuries to the spinal column, as well as guiding clinical management. These classification systems were developed for use with blunt force trauma, but it is unknown whether they can be used for injuries to the spine caused by a gunshot wound.

This study aims to investigate whether classification systems such as the Thoracolumbar Injury Classification and Severity Score (TLICS) and the Denis Classification can be applied to spinal injuries as a result of gunshot wounds in addition to blunt force trauma.

A retrospective analysis of the trauma patient database registry from the University of Alabama at Birmingham was undertaken for gunshot and spine fracture ICD-9 codes. A total of 32 patients had sustained spinal injuries caused by a gunshot wound. Each patient was evaluated for location of spine fracture and vertebral structures involved, neurological involvement, stability, treatment, and follow-up status. We then applied the TLICS and Denis classification system to evaluate ease of application and usefulness.

A total of 32 patients were evaluated and found to have gunshot wounds that resulted in injury to the spinal vertebra, vertebral ligaments, intervertebral disk, or the spinal cord. The location of injuries ranged from C1 to L5 and varied in the type of fracture. Injuries that had neurological involvement correlated with injury to the posterior column (as per the Denis Classification). There was little correlation with the anterior or middle columns with neurological involvement. Of 32 patients, only 1 had received surgical treatment. This patient had a disruption of all three columns, but similarly, there were nine other patients whose injuries involved all three columns, and yet they did not receive surgery.

TLICS was very difficult to apply to gunshot wounds and the Denis system provided no prognostic information despite a relative ease of use. It is our opinion that a new classification system needs to be designed to specifically include the injury patterns seen from a gunshot wound. Also, there was a little evidence that abstaining from a surgical treatment would cause any significant short- or long-term problems for the patient. Involvement of the posterior column correlated with neurological involvement but does not implicate the need for surgery or debridement.

A rare subset of lateral mass fractures is the floating lateral mass fracture with fractures of the adjacent pedicle and lamina, which involves injury to two adjacent motion segments. Our objective is to describe this important subset in regards to the mechanism of injury, anatomical injury pattern, associated vascular injuries, neurological deficits, key radiographic features, and the type of stabilization required.

A retrospective study of all floating lateral mass fractures treated at two level I trauma centers from 2007 to 2012 was performed. All medical records and spinal imaging studies were reviewed to identify patient demographics, mechanism of injury, associated spinal and skeletal injuries, vascular injuries, neurological deficits, the radiographical injury pattern, surgical treatment perioperative complications, and postoperative results. Plain radiographs and CT scans were used to assess axial alignment, degree of rotational instability, segmental kyphosis, and sagittal displacement. CT angiography was used to evaluate and grade vertebral artery injuries. When available, MRI evaluation was used to evaluate soft tissue injuries.

Following institutional review board approval, 60 consecutive cases were identified from the trauma registry at two level I trauma institutes. The mean follow-up was 9 months (range, 0–42 months). Mean age was 36 years (range, 16–69 years). The most common levels were C6 (45%) and C5 (30%). The most common mechanisms of injury were high-speed motor vehicle accident (58%) and sports injury (18%). Rotational displacement manifested as anterolisthesis in 80% at the level below the lateral mass injury,13% at the level above, and 7% at both. Facet joint widening occurred at the level above and below in 63%, below only in 17%, above only in 12%, and no widening in 7%. Vertebral artery injuries occurred in 22%. MR (31 patients) demonstrated injury to the lower disc in 74%, above 10%, and a herniation in 32%. Neurological deficits occurred as radiculopathy in 60% and spinal cord injury in 31% (ASIA A2, B3, C2, and D4). External immobilization was initially chosen in eight patients (13%). All patients, who were treated nonoperatively, developed subluxation of greater than 3 mm in less than 3 weeks, and six of the eight underwent surgery. Ultimately, operative treatment was performed in 58 of the 60 patients. A single level ACDF was performed in nine (15%) patients. Six of the nine were followed at a minimum of 6 months, and five (83%) patients developed 3 mm of subluxation at the level above the fusion. A two-level anterior fusion alone was performed in 33 (57%) patients. Posterior fusion alone was performed in six (10%) patients. A combined anterior and posterior fusion was performed in seven (9%) patients. There were no wound infections or postoperative neurological deteriorations.

A floating lateral mass fracture results from a high-energy injury and involves two motion segments. Vertebral artery injuries and neurological deficits are common. Two-level anterior or posterior fusions are effective means of treatment, as conservative management or single level fusions are ineffective at providing anatomical alignment.

To the best of our knowledge, there is not an optimal classification for vertebral fracture nonunion (VFNU), this study is to investigate the value of establishment of the novel therapy-oriented classification of VFNU based on the manifestation of extended CT reconstruction images.

All of the senior patients suffered from thoracolumbar spine fracture (December 2009 to March 2013) were retrospectively reviewed, 36 cases of VFNU were included in this study according to inclusion criteria. The reducibility and stability of index vertebrae were evaluated with extended CT reconstruction images, and all patients with VFNU were divided into three subgroups, type A owns the reducibility and stability, which is recommended to treat by percutaneous vertebroplasty in extension posture, type B owns the reducibility, but lacks stability, which should be treated by in situ fixation and fusion in extension posture, type C loses the reducibility, which is eligible for the spine deformity correction by osteotomy or canal decompression. Whether the patients were treated according to this classification and the perioperative complication were recorded. The clinical outcome was investigated by the comparison of VAS and ODI in preoperation, 3 months after surgery and last follow-up, the transformation of profile of index vertebrae was evaluated radiographically with the local kyphotic Cobb angle and anterior height of VFNU vertebrae in the above time points.

Overall, 39 level of VFNU vertebrae in 36 patients were located in the region of T9 to L4, in which the thoracolumbar segments were compromised frequently, and 16 level of VFNU existed in L1. According to extended CT reconstruction images, 25 level of type A, 7 level of type B, 7 level of type C VFNU were identified. Overall, 24 cases of type A VFNU accepted percutaneous vertebroplasty in extension posture, 4 cases of type B VFNU were treated by in situ fixation and fusion in extension posture, but 2 of them also accepted percutaneous vertebroplasty in extension posture like type A patients, 6 cases of type C VFNU were treated by spinal deformity correction by osteotomy or decompression, no severe complication occurred in both of type A and type B patients, except that 2 patients of type B VFNU, who accepted PVP, had notable but asymptomatic bone cement leakage, however, 1 case of type C VFNU had a deep wound infection, and 1 case got heart function failure during perioperative period. The different treatment oriented by this novel classification could be effective in the corresponding types of VFNU, by which the VAS, ODI could be improved, local kyphotic angle, and anterior height of VFNU could be corrected significantly (p < 0.05).

The validity of this novel therapy–oriented classification has been investigated by clinical and finite element study, which is beneficial to make more accurate evaluation and select the eligible surgery procedure before operation, and decrease the rate of usage of aggressive operations, like spinal osteotomy and decompression, in the older patients.

There is no specific measure available for patients with spinal trauma to apply in comparative effectiveness analyses, which contributes to the present lack of consensus and ongoing controversies regarding the optimal treatment and evaluation of many types of spinal injuries. Therefore, the AOSpine Knowledge Forum on Spinal Cord Injury and Trauma initiated a project to develop and validate such an instrument, which includes both the patients' and health professionals' perspective. The International Classification of Functioning, Disability and Health (ICF) is used as the basis. The preparatory phase of this project focused on identifying all potentially meaningful ICF categories for patients with spinal trauma, excluding patients with complete paralysis and patients with polytrauma, from three different perspectives: research, expert, and patient perspective. The results of these studies created the necessary background for a consensus meeting during which a selection of core categories was decided.

The research perspective was covered by a systematic literature review, from 2000 to June 2013, identifying outcome measures focusing on the functioning and health of patients with spinal trauma. The content of these outcome measures was linked to the ICF using established linking rules. The expert perspective was explored through an international cross-sectional web-based survey among spine surgeons from the five AOSpine International world regions. The surgeons were asked to give their opinion on the relevance of a compilation of 143 ICF categories for patients with spinal trauma. The patient perspective was investigated in an international empirical cross-sectional multicenter study, using the general ICF Checklist of 128 categories as a reference.

Of 6,415 screened references, 217 were included in the systematic review, and 15 frequently used outcome measures were identified. The content of these measures was linked to 57 different ICF categories. A total of 150 AOSpine International members participated in the expert survey. Of 143 ICF categories included in the survey, 13 were identified as “definitely relevant” by ≥ 80% of the participants. The empirical study, including 187 patients from nine trauma centers in seven countries, yielded 38 ICF categories as the most important for ≥ 20% of the patients. Combining these results, the list of ICF categories presented at the consensus meeting included 157 different ICF categories at the first or second level (44 on the component body functions, 16 on body structures, 64 on activities and participation, and 33 on environmental factors). Overall, 11 experts from six countries attended the consensus meeting. Ultimately, a total of 25 ICF categories were selected for outcome measurement in adult spinal trauma patients. This core set included 9 categories from the component body functions, 14 from activities and participation, and 2 from environmental factors.

A formal consensus process integrating evidence and expert opinion led to a core set of ICF categories for outcome measurement in patients with spinal trauma. In future studies, the Patient Reported Outcome under development will be subjected to further validation and cross-cultural adaptation.

The AOSpine Thoracolumbar Spine Injury Classification System was recently published, but before establishing a treatment algorithm to accompany the classification, further investigation on the cause of current regional treatment variations is required. The objective of this study is to determine if the ability of a surgeon to correctly classify A3 (burst fractures with a single endplate involved) and A4 (burst fractures with both end plates involved) fractures were affected by either the region or the experience of the surgeon.

A survey was sent to 100 AOSpine members from all six AO regions of the world (North America, South America, Europe, Africa, Asia, and the Middle East) that had no prior knowledge of the new AOSpine Thoracolumbar Spine Injury Classification System. Respondents were asked to classify 25 cases, including 6 thoracolumbar burst fractures (A3 or A4). The current analysis focuses on the effect of region and experience on surgeons' ability to properly classify these controversial fractures.

All 100 surveyed surgeons completed the survey, and no significant regional variability in the ability to correctly classify burst fractures was identified (p > 0.50). Further analysis demonstrated that no region predisposed surgeons increasing the severity of burst fractures. Similarly, experience did not affect surgeons' ability to correctly classify burst fracture (p > 0.21).

Regional variation in the treatment of thoracolumbar burst fractures (A3 and A4) is not because of the differing radiographic interpretation of the fractures.

The purpose of this project is to describe a morphology-based subaxial cervical traumatic injury classification system. Similar to the effort put toward the thoracolumbar system, the goal was to develop a comprehensive yet simple classification system with high intra and interobserver reliability to be used for clinical and research purposes.

A subaxial cervical spine injury classification system was developed using a consensus process. All investigators were required to successfully grade 10 cases to demonstrate comprehension of the system before grading 30 additional cases on two occasions, 1 month apart. Kappa coefficients (κ) were calculated for interobserver and intraobserver reliability.

The classification system is based on the following three injury types: compression injuries (A), tension band injuries (B), and translational injuries (C), with additional descriptions for facet injuries, as well as patient-specific modifiers and neurologic status. Interobserver and intraobserver reliability was substantial for all injury subtypes (κ = 0.64 and 0.75, respectively).

The AOSpine subaxial cervical spine injury classification system demonstrated substantial reliability in this initial assessment, and could be a valuable tool for patient care and for research purposes.

While the majority of C1 fractures are treated nonoperatively with external immobilization, there is a subset of C1 fractures known to be unstable. In addition, current literature-based outcomes of nonoperatively managed C1 ring fractures have not been completely favorable, and therefore, leave room for treatment alternatives. Our goal was to evaluate a series of unstable C1 fractures treated with primary internal fixation without fusion (ORIF) to assess clinical and radiographical outcomes.

A retrospective review of all patients with C1 fractures between September 2002 and November 2012 identified 10 consecutive patients from a level I trauma center (Harborview Medical Center, Seattle, Washington United States) who were treated with primary internal fixation without fusion. EMR charts and radiographs were reviewed. The surgical technique consisted of a posterior cervical approach to C1 arch and open reduction utilizing bilateral C1 lateral mass screws connected transversely with a rod. Primary outcome measures included radiographical reduction, maintenance of reduction, ROM, and complications. Pre- and postoperative CT scans were utilized to assess reduction.

A total of 10 patients with mean age of 53 years were identified to have undergone primary C1 ORIF. The cohort consisted of eight males and two females of which eight unilateral sagittal split–type fractures and two Jefferson burst–type fractures were identified. Mean follow-up was 13 months. Of the 10 patients, there were 2 associated complications, 1 errant screw requiring return to the operating theater for reposition, and 1 osteonecrosis of the lateral mass though the fracture healed. Preoperative lateral mass displacement averaged 7.3 mm and postoperative displacement had a mean of 2.4 mm with a p value after reduction of < 0.002. No patient had serious complication resulting in neurologic deficit or vascular injury associated with the procedure. No patient went on to develop the previously described “cock-robin” deformity from subluxation of the lateral mass with settling of the occiput onto the C2 lateral mass and no patient had subsequent C1–C2 instability as defined by an ADI greater than 3 mm on flexion and extension films.

Patients with unstable C1 ring fractures can be successfully managed with primary open reduction and internal fixation with a transversely oriented construct using C1 lateral mass screws. Open reduction and internal fixation offers a viable treatment alternative to conservative management or fusion by restoring cervical alignment with C1 reduction and anatomical realignment. Internal fixation of the atlas without fusion prevents progressive, painful deformity, and the need for complex occipitocervical reconstruction procedures that have been reported with nonoperative management of these injuries.

There is a continued amount of controversy in the optimal treatment of unilateral cervical facet fractures. Historical data and previous studies have shown that nondisplaced unilateral facet fractures treated nonoperatively may have a potentially unacceptable high rate of displacement leading to failure (range, 20–80%). The goal of this study was to analyze the success rate of cervical facet fractures treated nonoperatively in either a hard collar or Halo immobilization; while secondarily identifying risk factors for failure of nonoperative treatment that lead to delayed surgical intervention.

Retrospective review of 65 patients diagnosed with isolated, unilateral cervical facet fractures without dislocation, or spinal cord injury that were treated either a hard collar (n = 58) or halo vest (n = 7). Outcomes were analyzed with end points radiographic healing, clearance of collar in clinic, or failure of nonoperative management as measured by subluxation, new onset of neurologic deficits, or debilitating pain leading to delayed surgical intervention. The nonoperative failure group was further radiographically analyzed for risk factors of failure.

A total of 65 patients at a single Level I trauma center over the time period of 2005 to 2012 were included. Five spine surgeons at one institution participated in the care of these patients.

Retrospective review of injury computed tomography and plain films of patients diagnosed with unilateral cervical facet fractures were evaluated and included based on presence of an isolated or primary facet fracture pattern, absence of facet dislocation or perch, and documented clinical follow-up.

Of the 65 facet fractures treated nonoperatively, 7 patients failed (10.8%), as measured by subluxation, persistent or increased radiculopathy, and/or continued pain requiring operative intervention. There were 58 facets (89%) successfully treated nonoperatively in this study as deemed by clearance of collar and radiographic stability at the time of final follow-up. In the failure group, 85% of these patients had an absolute fracture height of greater than 0.9 mm and greater than 60% of the intact lateral mass; with the one outlier less than 0.9 mm having a previous ACDF.

Several published articles in the available literature on unilateral cervical facet fractures support operative intervention with relatively few advocating nonoperative treatment. At this time, our study has found a significantly lower observed failure rate in the nonoperative group when compared with historical data.

To our knowledge, this is the single largest collection of nonoperatively treated cervical facet fractures in published literature. On the basis of this data, nondisplaced cervical facet fractures in the neurologically intact patient warrant a trial period of nonoperative management. Although continued investigation of risk factors for failure of nonoperatively treated fractures is needed, patients should be educated about the potential risks and complications of each treatment modality. Consistent with previous work by Spector et al, all the nonoperative failures demonstrated fracture height approaching 1 cm and at least 40% of the intact lateral mass. A larger prospective study would be beneficial to correlate exact radiographic predisposition of facet fractures for failure with long-term patient outcomes.

When C1 arch displaced laterally in C1 bursting fracture, anatomical change between displaced bone and surrounding neurovascular structures can make placing C1 screw more challenging. This study was to describe the effect of the C1 bursting fracture on the location of the internal carotid artery (ICA) around the atlas.

The authors analyzed the morphology of the atlas and the ICA in 15 patients with C1 bursting fracture and compared the anatomical parameters with control group (77 patients) without any bone fractures or pathologies. All patients were evaluated with CT angiography for the assessment of anatomical parameter. The laterality of the ICA was classified into the following four groups: group 1 (lateral to the C1 lateral mass), group 2 (lateral half of the lateral mass), group 3 (medial half of the lateral mass), and group 4 (medial to the lateral mass). The distances of the ICA from the midline, anterior tubercle, and ventral surface of the C1 lateral mass were compared between two groups. The distance between the lateral margin of the longus capitis muscle and the inner edge of the transverse foramen was also measured.

Medially located ICA (laterality groups 2 and 3) was more common in the C1 bursting fracture group than control group (76.7 vs. 42.8%). There were no significant differences between two groups for the distance from the midline, the distance from the anterior tubercle, and the distance from the ventral surface of the C1 lateral mass, respectively. The distance of the longus capitis muscle to transverse foramen was 2.52 ± 2.09 and 4.15 ± 3.09 mm in each group, and there was statistically significant difference (p < 0.01).

Lateral displacement of the bony structure of C1 bursting fracture changes the relative location of the ICA medially, which increase the injury risk during the bicortical C1 screw insertion. These data suggest that CT angiography or enhanced CT scans may be essential study for C1 bursting fracture. These preoperative imaging studies can give information to choose the ideal fixation technique and the proper trajectory of the screws.

The AOSpine Thoracolumbar Spine Injury Classification System was recently published and combines elements of both the Magerl system and the Thoracolumbar Injury Classification System (TLICS); however, the worldwide applicability has yet to be established.

A previously described classification system of thoracolumbar injuries which consists of a morphologic classification of the fracture, a grading system for the neurologic status and relevant patient-specific modifiers was applied to 25 cases by 100 spinal surgeons from across the world twice independently, in grading sessions 1 month apart. The results were analyzed for classification reliability using the Kappa coefficient (κ).

The overall Kappa coefficient for all cases was 0.56 which represents moderate reliability. Kappa values describing interobserver agreement were 0.80 for type A injuries, 0.68 for type B injuries, and 0.72 for type C injuries, all representing substantial reliability. The lowest level of agreement for specific subtypes was for fracture subtype A4 (Kappa = 0.19). Intraobserver analysis demonstrated overall average Kappa statistic for subtype grading of 0.68 also representing substantial reproducibility.

In a worldwide sample of spinal surgeons without previous exposure to the recently described AOSpine Thoracolumbar Spine Injury Classification System, we demonstrated moderate interobserver and substantial intraobserver reliability. These results suggest that most spine surgeons can reliably apply this system to spine trauma patients as or more reliably than previously described systems.

Cervical spine injury is the common missed finding during the head injury. As the victims of the same will be unconscious in most occasions, clinical evaluation is difficult and we need to rely on investigation as well as clinical examination. It is important to rule out and manage appropriately to attain the proper outcome.

Patients with head injury who were less than GCS 8 and clinical evidence of spinal injuries were added in this study at a tertiary trauma care center at South India for past 4 years. Patients were screened with CT C spine along with CT head on initial evaluation. Any evidence of cervical spinal injury in both imaging and/or clinical examination underwent MRI spine. Treatment initiated appropriately. In a series of 524 patients with GCS less than 8 from May 2010 to May 2014, 74 patients underwent MRI spine based on CT C spine and clinical examination pertaining to cervical spine injury. Patients with thoracic and lumbar spinal injuries were excluded from the study. Follow-up made through clinical visits and telephonic enquiry.

A total of 47 patients had evidence of cervical spine injury in the form of contusions, altered signal changes, spinal stable and unstable fractures, and ligamentous injury. All patients received appropriate treatment including spinal fixation and continuous rehabilitation. Overall, 19 patients presented with unstable spinal fracture which needs stabilization. Overall, eight patients had extensive spinal cord contusions or altered signal changes. Overall, 17 patients had disc bulges or ligamentous injuries with cord signal changes. Overall, two patients had epidural hematoma.

Assessment and diagnosing the cervical spine injury is a real challenge in severe head injury victims. Strict protocol and appropriate management are the key to the success for the proper outcome. CT C spine and clinical examination during the initial evaluation help in attaining the goal and in early decision making.

Spinal dural arteriovenous fistulas (SDAVFs) are rare but most common form of spinal vascular malformations, accounting for approximately 70% of all such lesions. They are low-flow vascular shunts fed by radicular arteries. Patients most often present with myelopathy. The presumed pathophysiological mechanism is venous hypertension and congestion of the cord with edema. We present our experiences and results in combined endovascular and surgical treatment of type I SDAVFs.

We conducted a retrospective review of prospectively collected data from patients with a diagnosis of SDAVFs who underwent treatment at University Hospital Centre Rebro Zagreb between January 2012 and June 2014. The complication and recurrence rates from clinical and imaging follow-up in these patients are analyzed.

A total of 14 patients with a diagnosis of SDAVFs were treated in our institution during the analyzed period. Of these, 12 patients underwent endovascular embolization as first-line therapy. Onyx was used in 1 patient and NBCA in 11 patients. Two patients underwent surgical ligation as the initial therapeutic procedure. Patients in both groups showed significant improvement in clinical status after treatment on the Aminoff-Logue Scale. One patient in the endovascular group developed spinal infarction because of the accidental embolization of posterior spinal artery. Six patients in embolization group had recurrence of the fistula during the course of follow-up requiring surgical ligation. Two patients in the surgical group had recurrence of fistula during the course of follow-up and were reoperated.

Although most type I SDAFs are amenable to endovascular embolization, microsurgical obliteration as first option is indicated in specific anatomic situations and usually the only solution for recurrent cases. The combined endovascular and microsurgical approach offers best results after careful selection of patients based on imaging.

Intradural extramedullary spinal tumors are rare lesions, with a prevalence of 3 to 10 per 100,000 in general population. Open bilateral laminectomy with partial or total facet removal is the standard surgical access for gross total resection (GTR) of such tumors. Studies in patients operated with laminectomy, the risk of developing postoperative deformity, particularly in the cervical spine, is still significant, accounting of 20 to 60% of patients treated with laminectomy. In addition, ventrolateral or ventrally placed tumors are often not easily accessible through a standard translaminar approach. In the present series, preoperative MRI data and intraoperative three-dimensional (3D) fluoroscopic images are manually merged in the operating room. Minimally invasive surgical techniques through a tubular retractor system are then used to resect the tumor. The merged images are used to plan the ideal trajectory to the lesion, thus, facilitating tumor access while minimizing bone and soft tissue resection in these patients.

A retrospective chart review of 45 consecutive surgical cases of intradural tumors over a 7-year period was performed. Eight patients operated for intradural extramedullary tumors using the image merge technique. Preoperative MRI and intraoperative 3D fluoroscopic data were manually merged using Synergy Cranial 2.2 software and Stealth Merge 1.2. Accuracy of manual image merging was verified with anatomic landmarks as references. Using these merged images, a trajectory from skin to tumor is planned to facilitate microsurgical tumor resection. The trajectory chosen defines the skin incision, and the type and extent of bone resection. Following 3 to 4 cm skin incision, a transmuscular expandable retractor is “docked” onto the spine. Bone drilling is tailored to the tumor margins using the merged images. From this point on, standard microsurgical resection is performed, followed by dural closure.

From December 2012 to September 2014, five male and three female patients underwent tubular resection of intradural extramedullary spine tumors with the image merge assistance. Preoperative Nurick score was 3 in three patients, 1 in two patients, and 0 in remaining three patients. Follow-up neurological Nurick scores recording reveal a favorable neurological outcome with a score of 0 in seven patients. Follow-up ranges from 2 to 14 months (average, 5.8 months). No patient showed postoperative neurological deterioration. Only one patient with a resected L1 Schwannoma complains of postoperative radicular pain, which is responsive to medical treatment. MRI confirmed GTR in all cases.

In this small series, image merge assisted minimally invasive resection of intradural extramedullary lesions achieves maximum tumor resection while minimizing spinal cord manipulation and tailoring bone resection to reduce the risk of postoperative instability. This appears to be a safe and feasible procedure for such lesions.

In cervical spine surgery, it is essential to use the magnification, however, the surgical operating microscope can be expensive, cumbersome, and difficult to set up. Whereas the use of no magnification may lead to failure in removing the disc completely with no improvement of the patient condition. VITOM is an exoscope, which is used in place of operation microscope. It is easy to use and it gives same size magnification as operation microscope. This is a prospective cohort study form July 2013 to February 2014 at Helen Joseph Hospital. This study aims to evaluate the efficacy of video telescope operating microscope (VITOM) as an alternative to operative microscope (OM) in cervical spinal surgery.

Patients undergoing spinal surgery were enrolled in a prospective cohort study between July 2013 to February 2014 at Helen Joseph Hospital. The age, sex, and operation-matched patients undergoing surgery using the standard OM served as the control group. During surgery, the VITOM system was used in place of the OM in 20 patients. Operative time, length of postoperative hospital stay, and intraoperative complications were assessed.

A total of 10 patients were studied in two equal cohorts of 10 patients each. Within each cohort, patients underwent single-level and two-level cervical spine surgery. There were no significant differences in age or sex between cohorts. There were no statistically significant differences in mean operative room time for single-level decompressions and two-level decompressions. Postoperative length of hospital stay averaged 4 days for the VITOM group versus 5 days for the traditional OM group. Subjectively, surgeon opinion was the quality of image was much higher as compared with operating microscope.

The VITOM system provides as good a result as compared with operating microscope. However, there was no statically difference in the duration of patient stay in hospital and length of operation and interoperative complications. However, VITOM provide good visualization and better picture quality because of the high-resolution image. It is convenient also for teaching the purpose as well.

Since the introduction of vertebroplasty to clinical practice, the cement leak is considered the most frequent and hazardous complication. In literature, the cement extravasation ranged from 26 to 97% of the time. This study discussed a new technique for injecting cement in the affected vertebra.

A total of 123 patients were treated by vertebroplasty using the current technique. The package of the cement powder and the solvent was divided into five equal parts. Each part of the powder and the solvent was mixed as a single dose and injected to the affected vertebra. The duration between subsequent injections was 10 minutes. Each injection is formed of 1 to 1.5 mL of cement.

This new technique gives the surgeon enough time to make multiple separate injections with the same package. The time interval between injections makes cement harden enough and makes it not pushed by the next cement injection. This technique of injection gives time to the injected cement to seal off the cracks and cavities in the vertebra and subsequently leads to a highly significant decreased in cement leak (p < 0.001) compared with the literature.

This study demonstrates a previously unreported technique for vertebroplasty that adds more safety to the procedure by significantly decreasing cement leak. It also gives the surgeon much more relaxation time and self-confidence during performing the procedure.

Intraoperative computed tomography (CT) and navigation systems have several potential uses in instrumented spine surgery and may decrease patient morbidity and complications leading to very significant cost-effectiveness implications. Despite these proposed advantages, its adaptation in centers across Canada, New Zealand, and Australia is not ubiquitous. The goal of this study is to identify facilitators and barriers to the adoption of intraoperative CT and navigation systems technology by spine surgeons.

A web-based survey was designed to explore spine surgeons' perceived advantages and disadvantages of the use of intraoperative CT and navigation systems, the learning curve of the technology, its teaching utility, and surgeon comfort level with the technology. Questions were based on the unified theory of acceptance and use of technology (UTAUT) model, which explores four main constructs that directly determine user acceptance and usage behavior: performance expectancy, effort expectancy, social influence, and facilitating conditions. The survey was distributed to surgeon members of the Canadian, New Zealand, and Australian Spine Societies. Participants were stratified into 2 groups: users and non-users of intra-operative CT and navigation, with a slight variability in questions answered by both groups based on applicability.

A total of 53 surgeons completed the survey (34 Canadians, 16 New Zealanders, and 4 Australians). Overall, 24 of them are users of an intraoperative CT and navigation systems, and 29 are nonusers. The top three advantages identified by both users and nonusers in order of importance were more accurate screw placement, safer screw placement, and reassurance and confirmation of optimal screw placement. The top two disadvantages identified by both users and nonusers were the expense to purchase and maintain the equipment and the exposure of patient to radiation. The third main concern for nonusers is the time consumption associated with the use of this technology, whereas for surgeons who do use it, a disadvantage was that the use of intraoperative CT and navigation is technician dependent. Another concern revealed by the survey is after intra-operative CT and navigation use is implemented at an institution, surgeons think that the use of this technology may present an increased risk of infection (58.3% of surgeons who use it are concerned about this). Surgeons who have adopted this technology have done so primarily due to its clinical efficacy with screw placement, whereas surgeons who have not adopted intra-operative CT and navigation identify the cost of this technology as a limiting factor.

Spine surgeons recognize the benefit of using intraoperative CT and navigation systems to improve screw placement accuracy and safety. The cost associated with this new technology is the biggest deterrent to its widespread adoption in spine surgery centers in Canada, New Zealand, and Australia. Cost-benefit analysis evaluating the use of this technology would be useful in helping surgeons and health care centers make informed decisions about whether or not this investment is warranted.

Pedicle screw instrumentation in revision spinal surgery can be challenging because of the altered anatomy and existing instrumentation. Malpositioned pedicle screws can result in surgical complications that may lead to persistent pain, dysfunction, and morbidity. Robotic-guided screw placement has been shown to be accurate in the setting of primary surgery, however, less is known about its accuracy in revision situations. The purpose of this study was to identify the accuracy rate of pedicle screws placed via robotic guidance in revision spine surgery.

Patients who underwent revision spinal instrumentation with robotic guidance during a 3-year period (2011–2014) at our institution were identified and included in the study if they had postoperative CT scans of the operated levels. Screw insertion was identified in revision levels and included for analysis if they were categorized as screw redirection, prior fusion without instrumentation, prior laminectomy, or a spinal level adjacent to a previously operated level. Postoperative CT scans were reviewed for pedicle screw accuracy by independent radiologists.

A total of 36 patients met inclusion criteria (average age 61.6 years, 13 males and 26 females). Of the 682 total pedicle screws placed, 229 were placed in revision levels. Overall, 220 (96.1%) of the 229 revision screws were confirmed to be accurate by postoperative CT. Of the nine screws that were malpositioned, none were clinically significant nor required revision surgery. Of the nine malpositioned screws, there were five lateral breaches, and four medial breaches. One patient required revision surgery for cage migration at a similar level as a misplaced screw, however, pedicle screws were not revised.

Robotic-assisted pedicle screw placement in revision spinal surgery provides accuracy similar to other techniques in primary cases. In cases of previous laminectomy or fusion, robotic guidance can provide benefit to surgeons in navigating altered bony anatomy. Larger studies are needed to confirm these findings.

Determining optimal treatment of metastatic disease of the spine is difficult. Decision making revolves around neurological status, stability, and patient factors; histology the most important as specifically linked to life expectancy. Traditionally, limited life expectancy eliminated surgery as an option, but with minimally invasive techniques this paradigm is changing. Metastatic lung cancer generally has poor life expectancy and most patients are not offered surgery; but are there some patients with lung cancer who would benefit from surgery? Recently, molecular sequencing has led to better specificity than the traditional small cell, non-small cell (NSCLC) dichotomy and thus betters prediction of life expectancy. The purpose of this study is to identify histopathological and clinical parameters related to life expectancy that would help guide optimal surgical decision making for metastatic disease of the spine secondary to lung cancer.

A systematic review was conducted to answer the following questions: Q1. Determine the current survival patterns in the lung Ca population. Q2. Identify prognostic factors influencing survival and outcome in patients with lung Ca.

A total of 20 studies met the preset inclusion criteria. All included studies were retrospective series with a level of evidence of IV. The overall survival of patients with metastatic lung carcinoma is poor ranging from 5 to 17.8 months. Included studies consistently showed a better prognosis for patients with adenocarcinoma. The presence of EGFR mutation was also associated with a mild increase in life expectancy compared with the other histological subtypes.

Although life expectancy in patients with metastatic lung Ca is still in general not good, a subset of patients with adenocarcinoma and patients with EGFR mutations seem to have a better overall survival. Previously identified clinical and imagiological prognostic factors are still valid, but histology and specific mutations should be factored in the decision making when dealing with patients with lung Ca and MESSC.

Spinal hemangiomas are the most common tumor of the spine, being identified in 2 to 27% of patients at autopsy and on radiographic and magnetic resonance imaging studies. The majority of spinal hemangiomas are identified incidentally with only 1% presenting with symptoms, including pain, pathologic fracture, or neurologic compromise. Because of the rarity of symptomatic presentation, optimal surgical treatment of, and risk factors for local recurrence and mortality associated with, symptomatic spinal hemangiomas remain unclear. This multicenter cohort study aims to quantify rates of local recurrence and mortality following surgical treatment of symptomatic spinal hemangiomas and to identify prognostic variables for local disease control and death.

Patient and Methods: AOSpine knowledge forum tumor investigators created an ambispective database of surgically treated patients with symptomatic spinal hemangiomas. Patient data pertaining to demographics, clinical presentation, diagnosis, treatment, cross-sectional survival, local recurrence, and perioperative morbidity were collected. Tumors were classified according to Enneking and Weinstein–Boriani–Biagini. Descriptive statistics were summarized and Kaplan–Meier curves illustrated mortality and recurrence. Fisher exact and log-rank tests identified prognostic variables for recurrence and mortality.

Between 1996 and 2012, 68 patients (mean age = 51 years, SD = 16), 43 females and 25 males, underwent surgical treatment for a spinal hemangioma with 23% (n = 13) classified as benign aggressive. Epidural tumor extension was present in 55% of patients (n = 33). Pain was a presenting symptom in 82% (n = 54), 31% (n = 20) had a pathologic fracture, and 37% (n = 24) were neurologically compromised. Overall, 23 patients (35%) underwent preoperative embolization. Enneking appropriate surgery was performed in 79% of patients (n = 44). Adjuvant radiotherapy was employed in 10% of patients (n = 7). The local recurrence rate was 3% (n = 2) with no recurrences in patients undergoing marginal or wide resection. Mortality because of the spinal hemangioma was not observed during the study period (mean follow-up = 3.9 years, SD = 3.8). Prior subtotal intralesional resection was performed in one of the two patients who had a local recurrence.

This is the largest multicenter surgical cohort of spinal hemangiomas. Although symptomatic spinal hemangiomas frequently present with epidural disease and neurologic compromise, they remain a benign tumor. Thus, formal en bloc resection, with an associated risk and increased morbidity, is not required, and excellent rates of local control and long-term survival can be obtained when strict oncologic treatment principles are followed during the index surgery.

Primary spinal chondrosarcomas are rare. Best available evidence consists of small case series, making it difficult to determine optimal management and risk factors for local recurrence and mortality. The application of the Enneking classification in the treatment of primary bone tumors in the appendicular skeleton has led to a longer life expectancy, yet the application of the Enneking system in the treatment of primary bone tumors in the spine has not been widely accepted. Therefore, the aim of this multicenter cohort study was to determine prognostic variables, including application of the Enneking classification, for local recurrence and mortality following surgical intervention for spinal chondrosarcomas.

AOSpine knowledge forum tumor developed a multicenter ambispective database of surgically treated patients with spinal chondrosarcoma. Patient data pertaining to demographics, diagnosis, treatment, cross-sectional survival, and local recurrence were collected. Tumors were classified according to the Enneking classification. Patients were analyzed in the following two different cohorts; Enneking appropriate (EA) and Enneking inappropriate (EI). EA was defined by the final pathology margin matching the Enneking recommended surgical margin and EI by not matching.

Between 1987 and 2011, 112 patients (mean age at surgery = 47 ± 16 years) underwent surgical treatment for a primary spinal chondrosarcoma. EA surgery was performed in 61 (58%) patients. Overall, 15 patients (25%) suffered a local recurrence in the EA group and 21 (48%) in the EI group. EI approach significantly increased the risk for local recurrence (p = 0.009). Overall, 38 (34%) patients died during the study period (mean follow-up = 3.6 ± 3.2 years); factors associated with increased overall survival were absence of adjuvant therapy (p = 0.002), low-grade tumors (p = 0.051), and involvement of one or two vertebral levels (p = 0.038). Enneking appropriateness and surgical margin was not significantly associated with survival. Local recurrence was strongly related to mortality, with an odds ratio of 7.4.

This is the largest multicenter cohort of spinal chondrosarcomas. EI surgical management correlated with increased rates of local recurrence. This robust correlation strongly mandates to surgeons perform an EA resection with disease-free margins for spinal chondrosarcomas.

Primary spinal osteosarcomas are rare and aggressive neoplasms with poor outcomes. Enneking appropriate, en bloc resection is recommended for appendicular osteosarcomas. Obtaining even marginal margins is technically demanding in the spine, resulting in significant morbidity and possible functional sacrifice. The aim of this study was to identify prognostic variables on local recurrence and mortality, in surgically treated patients diagnosed with a primary osteosarcoma of the spine.

A multicenter ambispective database of surgically treated patients with primary spine osteosarcomas was developed by the AOSpine knowledge forum tumor. Patient demographic, diagnosis, treatment, perioperative morbidity, local recurrence, and cross-sectional survival data were collected. Tumors were classified according to Enneking principles and analyzed in the following two cohorts: Enneking appropriate (EA) and Enneking inappropriate (EI). EA was defined by the final pathology margin matching the Enneking recommended surgical margin and EI by not matching. Prognostic variables including age, previous spine tumor operation, biopsy type, spine level, tumor size, and chemotherapy timing were analyzed in reference to local recurrence and survival.

Between 1987 and 2012, 57 patients (31 females and 26 males) underwent surgical treatment for a primary spinal osteosarcoma at a mean age of 36 ± 16 years. Patients were followed for a mean period of 3.4 ± 3.5 years (range, 0.5 days–14.3 years). Median survival for the entire cohort was 6.7 years postoperative. Overall, 24 (42%) patients died and 17 (30%) patients suffered a local recurrence, 10 (59%) of which died. Overall, 28 (52%) patients underwent EA resection while 26 (48%) patients were treated by EI resection. Median survival for patients with EA was 6.8 years postoperative, whereas median survival for EI patients was 3.7 years postoperatively (p = 0.062). EI patients were at a higher risk of local recurrence than EA patients (p = 0.002). Patient age, previous spine tumor operation, tumor size, spine level, and chemotherapy timing did not significantly influence recurrence and survival.

Osteosarcoma of the spine presents a significant challenge and most patients die from their disease in spite of aggressive surgery. There is a significant decrease in recurrence with en bloc resection when compared with intralesional resection.

Primary Ewing sarcoma of the spine is a challenging tumor to treat because of a high rate of local recurrence. The optimum role of surgery in the treatment of Ewing sarcoma is not clearly defined. The objective of this study was to analyze factors relevant to survival and local control in surgically treated patients diagnosed with primary Ewing sarcoma of the spine.

A multi-institutional international ambispective with cross-sectional follow-up data was gathered about patients who underwent surgery for primary Ewing sarcoma of the spine. The primary outcomes assessed were 5-year survival and local recurrence. Multiple variables including the Enneking appropriateness of the surgery were evaluated for relationships to the primary outcomes. An Enneking appropriate procedure for Ewing sarcoma is an en bloc resection with negative margins. Survival and recurrence were analyzed using Kaplan–Meier curves and log-rank tests.

A total of 59 patients diagnosed with primary Ewing sarcoma of the spine underwent surgery. Enneking appropriateness of surgery was known for 55 patients; 30 treated Enneking appropriately (EA) and 25 treated Enneking inappropriately (EI). The 5-year survival was 73% (n = 22) for EA patients and 48% (n = 12) for EI patients. Median survival was not achieved within 5-year postoperative for EA patients and was 2.2 years for EI patients (p = 0.124). Local recurrence occurred in 20% (n = 6) of patients with an EA procedure versus 48% (n = 11) of patients with an EI procedure. The rate of local control was favorable for EA-treated patients compared with EI-treated patients (p = 0.046).

Primary spinal Ewing sarcoma requires multidisciplinary treatment. An Enneking appropriate surgical procedure is associated with longer survival and better local control. An Enneking appropriate procedure, when feasible, should be the surgical treatment of choice for primary spinal Ewing sarcoma.

Intraoperative blood loss is one of the major problems faced during the surgical management of metastatic spinal diseases. Presently, this is replenished by allogeneic blood transfusion, placing severe strain on the limited blood resource all over the world. We feel that this problem can be addressed by introducing the use of salvaged blood in spine tumor surgery. We conducted the study to evaluate the feasibility of using intraoperative cell salvage (IOCS) in combination with leukocyte depletion filter (LDF) in eliminating tumor cells from blood salvaged during metastatic spine tumor surgery (MSTS). This is with the view to pave the path for use of IOCS–LDF in musculoskeletal oncological surgery.

A total of 50 consecutive patients with known primary epithelial tumor, who were offered surgery for metastatic spinal disease at our university hospital, were recruited. Blood samples were collected at three different stages during surgery: stage A, from the operative field before IOCS processing, stage B, after IOCS processing, and stage C, after IOCS–LDF processing. Three separate 15 mL samples (5 mL each) were taken at each stage. The samples were examined by a cell block technique using immunohistochemical monoclonal antibodies to identify tumor cells of epithelial origin in the blood samples.

We hypothesized that the proportion of patients with tumor cells negative in stage C is much smaller or negligible than that in stage A. To test this hypothesis, the proportion of patients with tumor cell negative in stages A and C was compared using two-sample proportion test. The difference in that proportion between stages A and B was also compared.

Of the 50 patients, 10 were excluded for not fulfilling the inclusion criteria leaving 40 patients. Malignant cells of epithelial origin were detected in the samples taken from stage A, that is, the operative field before IOCS processing in 16 out of the 40 patients and in the samples from stage B, that is, the transfusion bag postcell-saver processing in 4 out of 40 patients. No viable malignant cells were detectable in any of the blood samples taken from stage C where the salvaged blood was filtered with LDF. Therefore, the proportion of patients with negative tumor cells in the samples taken from operative field was 60% (95% CI: 43–75%) and that in the samples taken from the transfusion bag post-IOCS processing was 90% (95% CI: 76–97%). All patients (100%) had negative tumor cells in the samples which were processed and filtered with both IOCS and LDF. Proportion test revealed that there was a significant difference between the proportion of patients with negative tumor cells in stages A and C (p < 0.01), providing the evidence that IOCS–LDF was able to eliminate all the tumor cells in salvaged blood. This significant difference was also observed between stages A and B (p < 0.01), indicating IOCS alone could be adequate for removing tumor cells.

The findings support the notion that IOCS–LDF combination works effectively in eliminating tumor cells from salvaged blood so this technique can possibly be applied successfully in spine tumor surgery and further be extended to the whole musculoskeletal tumor surgery.

Options for treating two-level symptomatic disc degeneration after failure of nonoperative care includes fusion, total disc replacement (TDR), or a hybrid with fusion at one level and TDR at the other. Often the hybrid procedure involved an instrumented 360 fusion. However, the option for a standalone ALIF in a hybrid has rarely been addressed. The purpose of this study was to compare the outcomes of hybrid TDR/fusion surgery for ALIF versus 360 at the fusion level.

The study group included 135 patients undergoing hybrid surgery using TDR at one level and either ALIF (n = 83) or instrumented 360 fusion (n = 52) at the adjacent segment. The majority of cases were performed with TDR at L4–L5 and fusion at L5–S1. Only patients who had surgery at least 12 months before this study were included. The mean length of follow-up was similar in the two groups (∼24 months in both groups). Outcome measures included Oswestry Disability Index (ODI), visual analog scales (VAS) assessing back and leg pain, and reoperations.

The mean operative blood loss was significantly less in the hybrid/ALIF group compared with the hybrid/360 group (71.7 vs. 142.1 mL; p < 0.01). The mean ODI scores before surgery were approximately 46 in both the groups. The scores improved significantly in both groups to the means of about 30 (p < 0.01) with no significant difference between the two groups (p > 0.40). Mean VAS back and leg pain scores also improved significantly in both groups with no significant differences between groups (Fig. 1).

Fig. 1

Mean VAS back and leg pain scores improved in both groups (p < 0.01) with no significant differences between groups. post-op, postoperative; pre-op, preoperative; VAS, visual analog scales.

The reoperation rate was significantly greater in the hybrid/360 group than in the hybrid/ALIF group (23.1 vs. 3.6%; p < 0.01). Reoperations in the hybrid/360 group included six reoperations for removal of painful posterior instrumentation, one to treat a wound infection, one decompression of the fusion level of the hybrid, three were for treatment of a symptomatic adjacent segment, and two were due to TDR malpositioning or displacement. Hybrid/ALIF reoperations included two patients undergoing decompression for stenosis and one underwent fusion two levels above the index surgery.

This study found that the outcomes are similar between hybrids performed with ALIF versus 360 fusion adjacent to the TDR level with the exceptions of a significantly greater reoperation rate and mean blood loss in the hybrid/360 group. These results support that unless there is a defined indication for the posterior procedure, standalone ALIF is a viable option for lumbar hybrid surgery.

The management of early-onset pediatric deformity has been revolutionized by the development of adjustable growing rods. These rods contain a rare-earth magnet that rotates when triggered by an externally applied magnetic field resulting in rod elongation. This patient group includes those with underlying neuromuscular conditions who occasionally require further MRI of the neuraxis during development and, given the magnetic properties of the rod, they are conventionally contraindicated for this imaging modality once implanted. We have investigated the behavior of the MAGEC (Ellipse Technology) rod to determine whether MRI adversely affects the elongation properties of the rod or indeed directly causes any detrimental consequences, including rod elongation, shortening, heating, or significant artifact to outline implications for this patient group.

We designed an in-vitro experiment using two MAGEC rods secured in an MRI compatible restraint system to investigate MRI behavior of magnetic growing rods during scanning. We used a 1.5T Philips MRI and a restraint system designed to secure the rods within this environment. Repeated gradient echo multiscan sequence MRI of the neuraxis was performed to evaluate whether the rods elongated, contracted, or rotated during scanning, while we used MRI compatible heat-sensors attached to the outer housing of the rods to assess temperature changes. We also assessed the ability of the rods to lengthen after completion of the MRI and a phantom model to evaluate the amount of artifact induced by the rare-earth magnet.

During repeated MRI of the neuraxis, the MAGEC rod mechanism was not triggered; however, the rods did rotate to bring the internal rare-earth magnet in line with the surrounding electromagnetic field, while only small forces were generated causing rod movement within the restraint system. The ability of the rods to lengthen after MRI was not enhanced or impaired and no significant heating effect on the external rod housing was demonstrated. The assessment of imaging with a phantom model did reveal a significant degree of artifact up to 30 cm because of the presence of the magnet within the electromagnetic field and, therefore, only MRI of the head and cervical spine could be interpreted with normal placement of MAGEC rods within the pediatric patient.

This study demonstrated that there are no detrimental effects of MRI on the MAGEC rod. In addition, while the degree of the artifact demonstrated prohibits imaging of the thoracolumbar spine, the MRI images of the head and cervical spine remain unimpaired. Finally, we did not demonstrate any significant force acting on the rod by the electromagnetic field that would cause implant dislodgement or loosening during MRI.

Debate continues about the relative merits of anterior versus posterior surgery for multilevel cervical stenosis causing myelopathy. Conclusions from previous studies were limited because one- or two-level anterior surgeries have been compared with multilevel posterior cases. The objective of this study was to compare outcomes and complications of anterior versus posterior-based cervical procedures (≥ 4 levels) for patients with multilevel disease.

Data from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. A subset of patients with myelopathy involving four or five vertebrae was analyzed in this study. The outcome measures included NDI, modified-Japanese Orthopaedic Association scores, SF36v2, and Nurick grades. Adverse events were also collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days–2 years following surgery) were tabulated and stratified based on clinical factors.

Of the 264 patients in the main study, 113 patients (42.8%) had four or more levels of surgery. There were 49 patients who underwent anterior cervical surgery (ACS, combination of anterior cervical decompression fusion ± corpectomy) and 64 patients who underwent posterior-based cervical surgeries (PCS, 45 laminectomy + fusion, 19 laminoplasty). There were statistically significant differences in age, cardiovascular comorbidities, and source of stenosis between these two groups. There was a statistically significant difference in baseline Nurick grades between groups (2.8 ACS vs. 3.3 PCS, p = 0.0075). There was no difference in any outcome measures at baseline. Outcome scores improved in both the ACS and PCS groups from baseline over a period of 2 years. There were no statistically significant differences between the anterior and posterior surgical procedures in terms of outcomes at 2 years (p > 0.05). This was true for NDI, mJOA, SF36v2, and Nurick scores for both unadjusted and adjusted analyses. There was no significant difference in complication rates between ACS and PCS groups. Each group had 14 reported complications (total 28). Both the groups reported two postoperative C5 radiculopathies. There was one reoperation in the ACS group. Worsening of neck pain was reported in one patient who had an anterior corpectomy/fusion procedure and there was one case of infection in the PCS group. Two patients in the ACS group had worsening of myelopathy.

In patients with four or five involved vertebral levels of pathology that require surgical intervention for cervical myelopathy, both anterior and posterior surgical procedures demonstrate improved outcomes. With this dataset, we found no evidence of difference between anterior versus posterior surgical procedures in outcomes or associated complication rates. Surgical decision-making related to approach and technique to address issues in these patients can be made by surgeons based on their judgment and experience with these procedures. The limitations of this study include (1) a nonrandomized study design and (2) the grouping together of different subtypes of anterior or posterior procedures.

Surgical site infections represent a major complication of spinal surgery. The application of lyophilized vancomycin into the wound is reported to significantly decrease infection rates. As concentrations applied locally can exceed the minimal bacterial inhibitory concentration for more than a 1000-fold, toxic side effects on local tissue may be possible.

Primary osteoblast cell cultures were generated from bone tissue samples of 10 patients. Samples were incubated in absence or presence of 3, 6, or 12 mg/cm² vancomycin according to a planned phase I clinical trial protocol. Changes in pH, osteoblast migration, proliferation, and viability were analyzed. Alkaline phosphatase and mineralization patterns were studied.

The application of more than 3 mg/cm² vancomycin induced a decline of pH toward the acidic range. The migration potential of osteoblasts was decreased from 100% (control samples) to zero (12 mg/cm² vancomycin) in a dose-dependent manner. Cell proliferation was significantly inhibited at dosages above 3 mg/cm². Significant cell death was observed if the dosage applied exceeded 6 mg/cm². The synthesis of alkaline phosphatase was markedly reduced in all dosages applied and calcium deposition was significantly decreased in dosages above 3 mg/cm².

As bone remodeling requires the immigration, proliferation, and differentiation of osteoblasts at the fusion site, high dosages of intrawound vancomycin might interfere with regenerative processes and increase the risk of nonunion. To allow an appropriate balance of infection risk and the risk of nonunion, the minimal local concentration required should be determined by controlled in vivo studies.

The current treatment of spinal metastasis consists of algorithms combining reconstructive surgical and radiation modalities. Recently, the concept of separation surgery followed by adjuvant stereotactic radiosurgery (SRS) was shown to be a safe and effective treatment to achieve long-term local tumor control. We examined the possibility of a minimally invasive approach to separation surgery first in a cadaveric feasibility study and then in a patient cohort with spinal metastasis in conjunction with intraoperative computer-assisted navigation.

A cadaveric study using standard minimally invasive access systems examined the feasibility of spinal cord decompression in the thoracic and lumbar spine. Subsequently, 10 patients (7 males and 3 females) with spinal metastasis underwent minimally invasive separation surgery (MISS) and percutaneous pedicle screw fixation using intraoperative navigation or standard fluoroscopy. The O-arm three-dimensional imaging with stereotactic navigation was used intraoperatively to localize and guide the resection of the metastatic spinal tumors. All patients were at least 3/5 strength in the lower extremities preoperatively. Pre- and postoperative CT scan and CT myelography were used to evaluate the degree of decompression. Endpoints included neurological function, operative time, estimated blood loss, incision length, hospital stay duration, and complications.

The cadaveric study demonstrated a proof of principle with a wide decompression of the spinal cord. For the operative cases, the postoperative imaging demonstrated excellent separation that meets the requirements for safe SRS. All patients remained at/or improved their neurological baseline with excellent pain control. One patient incurred a perioperative complication (pulmonary embolism). The mean estimated blood loss was 290 mL. The mean incision length was 4.9 cm. The operative time mean was 5.2 hours and the mean length of stay was 7.5 days.

MISS for spinal metastasis allows for a circumferential decompression of the spinal cord and safe postoperative SRS. In addition, we demonstrated the efficacy of intraoperative navigation in guiding the resection. Future prospective enrollment of patients can help to determine which patients would be ideal candidates for MISS and if the smaller incision and an enduring faster healing process can allow a faster start of radiation and chemotherapy.

The use of human adipose tissue-derived stem cells (hADSC) as therapy in spinal cord injury (SCI) is a promising approach for the recovery of motor function of injured patients. This study aims to evaluate the effects of hADSC, applied to the cauda equina in an animal model of blunt spinal trauma, on their motor function. A secondary aim is to analyze cell migration toward the injury site.

All samples were collected after an informed consent had been obtained in accordance with guidelines for research involving human subjects, and with the approval of the ethics committee (approval number 769). A total of 40 Wistar rats were anesthetized, injured at Th10 using the NYU impactor device and randomly divided into four groups: Group A, animals were submitted to one culture medium injection immediately after injury; group B, animals were submitted to two culture medium injections, immediately after and 7 days postlesion; group C, animals were submitted to one cell injection (1 × 10⁶ cells) immediately after injury and group D, animals were submitted to two cell injections, immediately after and 7 days postlesion. Standard animal care, according to the university's protocol was maintained for 40 days with motor analysis every 72 hours using the Basso, Beattie, and Bresnahan (BBB) scale. Some animals were transplanted with luc gene-transduced cells to evaluate cell migration, which was assessed by in vivo bioluminescence images of animals in groups C and D (IVIS Lumina II).

A statistically significant recovery of motor function was observed in animals transplanted with hADSC compared with the control group (p = 0.007 for one injection protocol, p = 0.005 for the two injection protocol). No differences were observed between one and two injection protocols (p = 0.13). Bioluminescence analysis revealed cell migration to the injury site after injection.

hADSC injected at the cauda equina migrate toward the injury site and promote significant motor recovery.

Due to their properties and characteristics, human mesenchymal stem cells (MSCs) appear to have great therapeutic potential, because they can contribute to the tissue regeneration. Many different populations of MSCs that differ for the embryonic origin and the anatomical localization have been described and to understand whether they have equivalent biological properties is a critical issue for their therapeutic application. Spine fusion is frequently used to treat traumatic, degenerative, and oncological spine diseases. Autologous bone graft has been considered the gold standard for spine fusion procedures because of its osteogenic, osteoinductive, and osteoconductive ability. However, its use is associated with significant disadvantages, including donor site pain, increased operative time, insufficient availability, and nonunion postlumbar fusion. Various bone substitutes have been developed to promote spinal fusion. Also, MSCs have been successfully tested for spinal fusion in several small and large animal models.

To define the properties of MSCs for the use in clinical applications, we proposed to analyze the cellular and molecular characteristics of human adult MSCs derived from different body locations, such as bone marrow from the iliac crest (Ic-MSCs), sternum (St-MSCs), and vertebrae (vMSCs), as well as colon (Co-MSCs) and dental pulp (DPSCs), to identify the cell population showing better biological properties for spine fusion clinical application.

MSCs from different sources presented very different growth kinetics. While iliac crest and sternum-derived MSCs could be maintained in culture for about 3 months, undergoing a limited expansion, mesenchymal cultures derived from dental pulp and colon grew much more rapidly, but could not be maintained longer. Strikingly, vMSCs continued to propagate at high rate even after 3.5 months ex vivo. MSCs from different sources were also induced to osteogenic, adipogenic, and chondrogenic differentiation following exposure to specific inducing agents. We observed that vMSCs generate mature cells of all mesenchymal lineages with greater efficiency, resulting into the best population both in terms of expansion and differentiation.

This finding could be very interesting and open new perspectives for the improvement of spine fusion, which is a mandatory step for the success of spinal surgical procedures. In the course of a surgical procedure for spinal fusion, vertebral bone marrow can be harvested simultaneously with the preparation of the site for pedicle screw insertion. Then multipotent MSCs can be isolated from vertebral bone marrow during the progress of the surgical procedure and reintroduced in the fusion site (using homologous or autologous bone tissue or biomaterials as scaffold), without any additional surgical time or any other donor site involvement.

Painful degenerating intact human intervertebral discs (IVDs) produce elevated levels of Toll-like receptors (TLRs), cytokines, and neuropeptides but events regulating their expression are poorly understood. Mechanical overload has been proposed as one potential initiating mechanism. The aim of this study was to investigate the cellular responses in IVDs and isolated disc cells exposed to mechanical overload or strain.

Lumbar spine segments were harvested from consenting donors via the Transplant Quebec organ donation program in Montreal, Quebec, Canada. A total of nine discs from six donors were used in this study. Intact IVDs were prepared and cells isolated using a standard technique. Intact discs with cartilaginous endplates were loaded with a single ramp compression peaking at either approximately 0.2 MPa (noninjurious) or about 1.5 MPa (injurious) stress applied at a rate of 30% strain per second. Injurious compression protocol consistently yields endplate fracture. Discs were immediately put in low serum containing media after loading. For isolated cell experiments, 2 × 10⁵ nucleus pulposus (NP) and annulus fibrosus (AF) cells were seeded on flexible or static silicone dishes. The flexible dishes were exposed to a 20% magnitude cyclic mechanical strain at 0.0001 Hz was applied to the cultures for 8 h/d over 2 days. Conditioned media was collected and RNA was isolated. Quantitative RT-PCR was performed to assess TLR, NGF, and TNF gene expression. Conditioned media from intact discs and isolated cells was applied to PC12 cells and neurite outgrowth was assessed. Commercially available cytokine arrays were used to investigate protein levels of cytokines released from intact discs and isolated cells.

Elevated levels of proteoglycan, inflammatory cytokines, and pain mediators were released from intact discs exposed to injurious loading. The highest levels were found 3 days postinjury and the conditioned media caused significantly induced neurite outgrowth in PC12 cells compared with that of the control group. About 50% of the cells in the IVDs died as a result of the inflicted trauma. Isolated NP and AF cells were exposed to a high-magnitude strain at low frequency to preserve cell attachments and maintain cell viability. The protocol was applied to evaluate if the adverse mechanical stimulation of the cells or the induced cell death caused by the injurious loading of the intact IVDs was responsible for the increased expression of inflammatory cytokines and pain mediators. Our data showed that high-magnitude low-frequency strain is sufficient to induce expression inflammatory cytokines and pain mediators in the absence of cell death. We also found a small but significant upregulation of TLR 2 and 4 in both NP and AF cells.

Cell death and cytokine production combined with loss of glycosaminoglycan indicate that mechanical injury to intact IVDs and isolated cells initiates cellular processes leading to disc degeneration. Once the proteoglycan content in the matrix has been degraded, elevated levels of NGF could lead to neuronal ingrowth directly causing pain. Increased TLR expression induced by high strain may prime cells toward a degenerate phenotype and could be a novel therapeutic target for degenerative disc disease.

Although a discectomy successfully relieves the neurological symptoms of a herniated intervertebral disc (IVD), it does not treat the underlying degenerative process; the annular defect remains unrepaired. Persistent annular defect is associated with an increased risk of recurrent herniation and progressive degenerative changes to the IVD. It may also be the primary cause of chronic low back pain following discectomy. To date, there is no established method for repairing annular defects in vivo. The presented study aims to determine whether injectable high-density collagen (HDC) gels can reduce further disc herniation and inhibit degenerative changes in a needle-punctured rat-tail model, and whether riboflavin (RF) cross-linking of injected collagen influences the repair process.

A total of 31 athymic rats were punctured with an 18-gauge needle in C3/4 of the caudal spine. They were divided into four groups: group 1 punctured and injected with HDC cross-linked with 0.5 mM (n = 6) or 0.75 mM (n = 7) RF; group 2 punctured and injected with noncross-linked collagen (n = 6); group 3 punctured and untreated (n = 8); group 4 punctured and injected with FITC-labeled cross-linked collagen (n = 4). Degenerative changes to punctured discs, NP size, and NP hydration were analyzed using X-ray, MRI), and histology. Functionality of repaired AF tissue was measured by mechanical tests, by comparing the hydraulic permeability of treated discs to that of healthy discs.

After 5 weeks, untreated discs showed signs of terminal degenerative changes on MRI and histological sections (Fig. 1). No NP tissue remained in the disc space. In contrast, discs treated with RF cross-linked collagen gels retained 63% of NP and 80% of disc height at 5 weeks, and showed minimal degenerative changes on histological section. Interestingly, a series of in vivo imaging showed that after 5 weeks, discs treated with cross-linked HDC demonstrated consistent improvement in both volume and hydration over time, while untreated discs and discs treated with noncross-linked HDC, lost volume, and water content. Injected collagen was seen to form a zipper-like adhesion to the host AF and connective tissue after 1 week and by 5 weeks a fibrous cap that persisted until 18 weeks. NP hydration and IVD functionality of treated discs were found to be similar to those of adjacent healthy discs at 18 weeks.

Fig. 1

An 18-week outcome examples from all punctured groups. Adjacent segments served as healthy controls. Specimen from noncross-linked and punctured, untreated groups showed degenerative changes on X-ray and MRI; these changes were attenuated in the RF cross-linked group. NP tissue from the RF cross-linked group appeared hyperintense on MRI and retained its ovular shape. MRI, magnetic resonance imaging; RF, riboflavin; NP, nucleus pulposus.

Injection of high-density collagen gel cross-linked with RF can repair annular defects, prevent the degenerative cascade, and maintain the functionality of IVDs in a rat-tail spine. Further studies will be performed to confirm the ability of HDC gels to repair annular defects in a large animal model.

COL6A1 and BMP-2 genes have been implicated in ossification of the posterior longitudinal ligament (OPLL) susceptibility in Japanese and Chinese Han populations. However, no study has yet investigated the DNA of unaffected family members of patients with OPLL. This study investigated differences in genetic polymorphisms of BMP-2 and COL6A1 between Korean patients with OPLL and their family members (with and without OPLL).

A total of 321 patients (110 patients with OPLL and 211 family members) were enrolled in the study. Associations between two single nucleotide polymorphisms (SNPs) of the BMP-2 gene (Ser37Ala and Ser87Ser) and two SNPs of COL6A1 (promoter [−572] and intron 33 [+20]) with susceptibility to OPLL of the cervical spine were investigated between the two groups (OPLL+ and OPLL − ).

Of the 321 patients, 162 had cervical OPLL (50.4%; 110 patients, 52 family members). There was a familial tendency of OPLL in 34 of the 110 families (30.9%). Allele and haplotype frequencies of the four SNPs in the BMP-2 and COL6A1 genes did not differ significantly between the OPLL+ and OPLL− groups, even when excluding participants over 50 years of age.

This is the first report identifying SNPs of COL6A1 and BMP-2 in Korean patients and family members with OPLL. Although allele and haplotype frequencies were similar to those of a previous study in Japanese and Chinese patients, unaffected family members also showed similar rates of these SNPs in the present study. These results suggest that these SNPs may not directly influence the expression of OPLL.

Discogenic low back pain (LBP) is generally caused by progressive intervertebral disc (IVD) degeneration associated with aging or trauma. Analgesic discography (discoblock) can be used to diagnose or treat discogenic LBP by injection of a small amount of local anesthetic. Lidocaine or bupivacaine is one of the most commonly used local anesthetics for discoblock. Several in vitro studies have reported dose- and time-dependent cytotoxic effects of these local anesthetics on IVD cells. In addition, a recent prospective, matched cohort clinical study showed that discography was associated with more extensive IVD degeneration at a 10-year follow-up. The present study aimed to investigate the deteriorating effects of lidocaine and bupivacaine on rabbit IVDs using an organotypic culture (ex vivo) model and an in vivo long-term follow-up model.

Ex vivo study: The IVDs were surgically harvested from rabbits. A 0.9% saline solution, 1% lidocaine, or 0.5% bupivacaine was intradiscally injected using a microsyringe with a 26-gauge needle. IVDs were divided into five groups: untreated control, puncture-only group, saline group, lidocaine group, and bupivacaine group. After 3 or 7 days of the injection NP tissues were stained with propidium iodide (dead cell) and Hoechst 33342 (live and dead cells). NP cell death was evaluated using a confocal laser scanning microscopy (n = 6). After 7 days of the injection histological analysis using hematoxylin and eosin (H&E) staining and TUNEL assays was performed on IVDs (n = 6). In vivo study: Rabbit lumbar IVDs were percutaneously punctured under a fluoroscopic guidance. Overall, 15 µL of 0.9% saline solution, 1% lidocaine, or 0.5% bupivacaine was injected into IVDs (L2/L3 and L4/L5). L3/L4 was left intact as a control. A sham procedure was performed by subjecting control animals to IVD needle puncture only. After 6 or 12 months of the injection, midsagittal images of the treated discs were analyzed qualitatively for evidence of degenerative changes using a 7.0 T MRI. After MRI analysis, histological analysis was performed on IVDs using Safranin-O fast green and H&E staining. Semiquantitative evaluation of disc degeneration was also performed.

Ex vivo study: Both anesthetic agents induced time-dependent NP cell death; when compared with an injected saline solution, significant effects were detected within 7 days. After 7 days, lidocaine and bupivacaine increased dead cells to 72 and 76%, respectively. The percentage of apoptotic NP cells in the lidocaine and bupivacaine groups was significantly higher than that in all other groups. In vivo study: MRI analysis showed no significant difference among the puncture, saline, and both anesthetic agent groups at 6 or 12 months. Histological assessment of IVDs revealed degenerative changes most severe in local anesthetic agent groups. However, there was no significant difference between the saline and anesthetic agent groups. After 12 months, there was a significant difference between anesthetic agent groups and untreated control groups in the number of NP cells.

Discoblock progressed IVD degeneration, but there was no strong evidence that the local anesthetics caused IVD degeneration in vivo rather than the initial mechanical damage of the pressurized injection.

While spinal fusion surgery has advanced over the past decade, a great deal is unknown regarding the underlying mechanisms that contribute to spinal fusion failure or pseudoarthrosis. Clinically, bone marrow aspirate has been successfully used alongside a variety of grafting materials to augment fusion (Neen et al. Spine (Phila Pa 1976). 2006;31(18):E636; Carter et al. Spine J. 2009;9(6):434). To date, studies evaluating these procedures have focused on radiographic monitoring and endpoint analysis. Little is known about the survival and proliferation of these transplanted mesenchymal cells or how much they contribute to bone formation compared with host cells from adjacent decorticated bone. Insights into these cell dynamics will give us a deeper understanding of the biological processes underlying spinal fusion and allow for evaluation and development of fusion therapies that reduce rates of pseudoarthrosis.

A total of 40 FVB/NJ mice underwent posterolateral lumbar spinal fusion surgery and were divided into four groups based upon the fusion graft employed: syngeneic iliac crest bone graft (n = 10), Vitoss bone-matrix alone (n = 10), Vitoss bone-matrix with syngeneic bone marrow cells (2.5 × 10⁶ cell/side) (n = 10), and Vitoss bone-matrix with transgenic luciferase-expressing syngeneic bone marrow cells (2.5 × 10⁶ cell/side) (n = 10). Bone marrow cells were isolated from the long bones of either syngeneic FVB/NJ mice or syngeneic FVB mice which constitutively express the luciferase gene (FVB-Tg (CAG-luc,-GFP) L2G85Chco/J mice). The in vivo survival, distribution, and proliferation of the luciferase-expressing bone marrow-derived cells were monitored via bioluminescence imaging over a period of 8 weeks. Spinal fusion was assessed 4, 6, and 8 weeks postsurgery via micro-CT imaging, as well as via manual palpation at 8 weeks. Immunohistochemistry was performed to assess fusion bone growth as well as determine the number of donor versus host cells within the fusion mass.

Bioluminescent imaging data demonstrated quantifiable cellular viability within the fusion mass as early as 24 hours following surgery, with increasing bioluminescent signal over the first 2 weeks postsurgery, thus indicating cellular proliferation. Bioluminescence decreased between weeks 4 and 8 suggesting a loss of transplanted mesenchymal progenitor cells within the fusion mass at later time points. Correlations with histology and micro-CT imaging of the developing fusion mass are currently under analysis.

We have demonstrated a novel murine model which enables noninvasive in vivo monitoring of implanted transgenic luciferase-expressing bone marrow cells following spinal fusion surgery. Future applications of this model will include the assessment of additional therapeutics for improving spinal fusion in translational research studies.

The human VANGL1 genes has been predicted to be associated with idiopathic scoliosis, as a mutation (c.676C > T, L226F) was identified in a family with dominant inheritance of the disease. A previous investigation of the gene revealed the candidate to segregate, with all but one family member (Sharma, et al. ASHG 2012 Annual Meeting Program Guide. 2012). Adolescent idiopathic scoliosis (AIS) is generally considered multigenetic, but the determining genes remain yet to be characterized. In this study, we have examined VANGL1 as a contributor to the phenotype of AIS.

We have conducted automated Sanger sequencing of the seven coding exons of VANGL1 gene in a disease cohort of 170 AIS patients (n = 340) and 177 controls (n = 354). Localization of mutated VANGL1 proteins was investigated in cell systems using immunofluorescence microscopy.

Two novel mutations, each in separate individuals within the considered disease cohort, were identified. One mutation is situated in the third coding exon, which encodes the transmembrane parts of the VANGL1 protein. This mutation is a c.407T > A (I136N) conversion, for which the patient is heterozygotes. Furthermore, this mutation was also identified in the dizygotic unaffected twin of the patient. The second mutation was found in the seventh coding exon, which encodes the C-terminal of the VANGL1 protein. This mutation is a c.1318T > G (F440V) conversion, for which the patient is also heterozygotes. Neither of the identified mutations was present in the sequenced controls or in 2000 Danish exomes (Lohmueller et al. Am J Hum Genet 2013;93:1072–1086). The F440V mutation results in altered localization of the VANGL1 protein, from very clear membrane association to a cytoplasmic distribution, with possible retainment in endoplasmic reticulum and the Golgi apparatus, near the cell nucleus.

Our results show that mutations in the VANGL1 gene can cause AIS and suggest that defects in planar cell polarity may be an underlying cause of AIS. Examination of the expression of VANGL1 in juvenile or adult stages of life is wanted, as well as examinations of effects on downstream targets of mutated VANGL1 and polarity in affected cells.

Sciatica caused by lumbar disc herniation is a frequent clinical condition. The development of the radicular pain is explained by mechanical and biological (inflammatory) factors. Spontaneous pain relief in the first weeks is not uncommon, but a significant part of the patients have got persistent (and/or recurrent) disabling pain requiring surgical intervention. The biological background of the alteration in clinical symptoms is still unknown.

The aim of this study was to investigate the protein and the mRNA expression of different cytokines in human herniated disc tissues.

A total of 24 patients who underwent lumbar microdiscectomy were included into the study. Sequestered disc tissue was collected during the surgery and analyzed using a Human Cytokine Array Panel (R&D Systems) and TaqMan Gene Expression Assays to determine the protein (n = 12) and mRNA expression (n = 12) of different cytokines. Cytokine expression levels were analyzed in relation to the duration of the symptoms (acute: less than 6 weeks, chronic: more than 3 months). Nonparametric statistical tests were used to determine significant differences in protein/mRNA expression. A minimum of 1.5-fold difference and p < 0.05 was considered significant.

IL-6, IL-8, and GRO-a were expressed significantly higher in acute disc herniations either in protein and mRNA levels. RANTES, IFN-g, and G-CSF proteins were found to be increased in chronic herniations and higher expression of RANTES and IFN-g were confirmed at mRNA level.

Cytokine profile in herniated disc tissue changes with time. It can be associated with an altered inflammation process and the consequent change of the clinical picture. New biological approach selectively modulating the inflammatory response can be one of the future developments in the nonsurgical management of intervertebral disc herniation.

The intervertebral disc (IVD) has a limited regenerative potential and low back pain represents a leading cause of disability.¹ IVD repair strategies require an appropriate cell source that is able to regenerate the damaged tissue such as progenitor stem cells. Recently, progenitor cells that are positive for the angiopoietin receptor (Tie2) in the nucleus pulposus were identified.² These cells, which express type II collagen and aggrecan, were shown to have progenitor-like multipotency. Here, we isolated primary cells from bovine IVD aged 1 year and sorted bovine nucleus pulposus progenitor cells (NPPC) for the marker Tie2. Furthermore, we demonstrate that in contrast to Tie2− cells, Tie2+ expressing cells can differentiate into osteogenic and adipogenic lineages in vitro.

NP cells were obtained from 1-year-old bovine tails by sequential digestion with Pronase for 1 hour and collagenase overnight. Sorted Tie2− and Tie2+ cells were cultured in osteogenic and adipogenic medium containing 5% fetal bovine serum for 3 weeks. The formed cell layers from both subpopulations were stained for calcium deposition and fat droplets using alizarin red and red oil staining, respectively. Colony forming units (CFU) were prepared for both cell suspensions (Tie2− and Tie2 + ) in methylcellulose-based medium. The formed colonies (> 10 cells) were analyzed macroscopically and counted after 8 days.

After 3 weeks of culture, sorted Tie2+ cells were able to differentiate into osteocytes and adipocytes as characterized by calcium deposition and fat droplet formation. By contrast, Tie2− cells generated a weak staining for calcium and no fat droplets were obtained (Fig. 1). Sorted Tie2− and Tie2+ subpopulations of cells, both the formed colonies, however with different morphologies. The colonies formed from Tie2+ cells were spheroid in shape, whereas those fromTie2− cells were spread and fibroblastic. In addition, the highest frequency of the formed colonies was obtained for the Tie2+ cells after 8 days of culture in the methylcellulose-based medium.

Fig. 1

Differentiation assays of Tie2+ and Tie2− bovine nucleus pulposus cells: Osteogenesis (top row) and adipogenesis (lower row).

Our data showed that Tie2+ cells of the nucleus pulposus cells are progenitor-like cells that are able to differentiate into osteogenic and adipogenic lineages. Sorting of NPPC for Tie2 may represent a promising strategy with the potential to be used in the clinics for treatment of intervertebral disc damage.

This project was funded by two projects of the Swiss National Science Foundation, grant numbers IZK0Z3_154384 and 310030_153411.

References

Freemont AJ. The cellular pathobiology of the degenerate intervertebral disc and discogenic back pain. Rheumatology (Oxford) 2009;48(1):5–10

Sakai D, Nakamura Y, Nakai T, et al. Exhaustion of nucleus pulposus progenitor cells with ageing and degeneration of the intervertebral disc. Nat Commun 2012;3:1264