Global Spine Journal

Retrospective review.

Large compressive pseudomeningocele causing a major neurologic deficit is a very rare complication that is not well described in the existing literature.

Institutional review board consent was obtained to study 2552 consecutive extradural spinal surgical cases performed by a single senior spinal surgeon during a 10-year period. The surgeon’s database for the decade was retrospectively reviewed and 3 cases involving postoperative major neurologic deficits caused by large compressive pseudomeningocele were identified.

The incidence of postoperative compressive pseudomeningocele causing major neurologic deficit was 0.12% (3/2552) per decade of spinal surgery with approximately 1.3% of cases incurring incidental durotomy. Average age of the patients was 57 years (range 45-78). One patient had posterior cervical spine surgery, and 2 patients had posterior lumbar surgery. All 3 patients had intraoperative incidental durotomy repaired during their index procedure. Large compressive pseudomeningocele causing major neurologic deficit occurred in the early 2-week postoperative period in all patients and was clearly identified on postoperative magnetic resonance imaging. All 3 patients were treated with emergent decompression and repair of the dural defect. All patients recovered neurologic function after revision surgery.

Incidental durotomy and repair causing a large compressive pseudomeningocele after spine surgery is a rare and potentially devastating event. Early postoperative magnetic resonance imaging assists in the diagnosis. Emergent decompression combined with revision dural repair surgery may result in improved outcomes. Surgeons should be cognizant of this rare cause of early postoperative major neurologic deficit in patients who had previous dural repair.

Retrospective database analysis.

The impact of the 2008-2009 economic downtown on elective lumbar spine surgery is unknown. Our objective was to investigate the effect of the economic downturn on the overall trends of elective lumbar spine surgery in the United States.

The Nationwide Inpatient Sample (NIS) was used in conjunction with US Census and macroeconomic data to determine historical trends. The economic downturn was defined as 2008 to 2009. Codes from the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), were used in order to identify appropriate procedures. Confidence intervals were determined using subgroup analysis techniques.

From 2003 to 2012, there was a 19.8% and 26.1% decrease in the number of lumbar discectomies and laminectomies, respectively. Over the same time period, there was a 56.4% increase in the number of lumbar spinal fusions. The trend of elective lumbar spine surgeries per 100 000 persons in the US population remained consistent from 2008 to 2009. The number of procedures decreased by 4.5% from 2010 to 2011, 7.6% from 2011 to 2012, and 3.1% from 2012 to 2013. The R ² value between the number of surgeries and the S&P 500 Index was statistically significant (P ≤ .05).

The economic downturn did not affect elective lumbar fusions, which increased in total from 2003 to 2013. The relationship between the S&P 500 Index and surgical trends suggests that during recessions, individuals may utilize other means, such as insurance, to cover procedural costs and reduce out-of-pocket expenditures, accounting for no impact of the economic downturn on surgical trends. These findings can assist multiple stakeholders in better understanding the interconnectedness of macroeconomics, policy, and elective lumbar spine surgery trends.

Retrospective cohort study.

To describe the readmission rate and identify risk factors associated with 30-day readmission after transforaminal lumbar interbody fusion (TLIF) surgery.

Patients who underwent elective single level TLIF surgery from 2011 to 2013 were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Emergency or trauma cases were excluded. Preoperative, intraoperative, and postoperative variables were extracted. A multivariate binary regression identified predictors correlated with 30-day readmission.

A total of 4992 patients were included in the analysis. The overall 30-day readmission rate was 5.51% (275/4992) for readmissions reported between 2011 to 2013. The mean age of patients readmitted was 62.40 years (standard error [SE] = 0.78) and 60.92 years (SE = 0.20) among those whom were not readmitted (P = .05). The top three causes for readmission included postoperative pain control, deep or superficial surgical site infections. Predictors associated with 30-day readmission in a multivariate analysis included female gender (odds ratio [OR] = 1.27, 95% CI = 0.97-1.65), history of severe chronic obstructive pulmonary disease (OR = 1.81, 95% CI = 1.11-2.96), and in the postoperative period, American Society of Anesthesiologists class (OR = 1.30, 95% CI = 1.04-1.63), presence of superficial surgical site infection (OR= 18.23, 95% CI = 10.36-32.08), or urinary tract infection (OR = 4.93, 95% CI = 2.84-8.58).

The readmission rate, risk factors, and causes following TLIF surgery are comparable to other lumbar spinal procedures reported from the ACS-NSQIP database.

Retrospective analysis of consecutive case series.

To introduce a novel method of stabilizing the cranium using bivector traction in posterior cervical fusions.

A retrospective review of 50 consecutive patients undergoing instrumented posterior cervical arthrodesis was performed. All patients had at least 3 levels of subaxial fusion using the bivector traction apparatus. Patients’ demographic data was recorded for the following: pre- and postoperative cervical lordosis, pre- and postoperative cervical sagittal vertical alignment (cSVA), and intraoperative complications from pin placements.

A total of 50 patients were studied. There were 31 females and 19 males. The mean age at the time of surgery was 49 years (range 35-79). A mean 5.8 levels were fused. The most common levels fused were C2-T3 in 14 patients followed by C2-T2 in 7 patients. In no case did the surgeon or assistant have to scrub out to adjust the alignment. The mean pre- and postoperative cervical lordosis was −6.0° and −10°, respectively (P = .04). The mean pre-and postoperative cSVA was 30.5 mm and 32 mm, respectively (P = .6). There were no complications related to placement of the Gardner-Well tongs.

The bivector traction is an easy, safe, and effective method of stabilizing the head and obtaining adequate cervical sagittal alignment.

Prospective cohort study.

Endplate lesions though have been implicated in the genesis of lumbar disc herniation (LDH), very little is known regarding their clinical course. Thus, the present study is aimed to investigate the incidence and types of endplate failure (EPF) in LDH and its correlation with the clinical symptoms and prognosis.

Clinical and magnetic resonance imaging (MRI) features of 66 patients with isolated single level LDH were studied. Three-dimensional fast spoiled gradient (3D FSPGR) MRI and computed tomography scans were used to identify the bony and cartilaginous EPF. Twenty-five patients were operated on and 41 patients were treated conservatively. Changes in the pain score, function and neurology were noted at 3, 6, 12, 24, and 36 weeks.

Endplate lesions were observed in 64 patients (96.9%), including bony endplate failure (bony failure) in 47 patients (71.2%) and isolated cartilaginous endplate lesions in 17 patients (25.7%). Bony failure group had similar pain and functional scores but more severe neurological deficit at the initial evaluation. Clinical parameters improved in all groups, but the recovery was lesser in conservatively treated bony failure patients.

Endplate lesions are commonly associated with symptomatic LDH. Presence of bony failure can increase neurological deficit and reduce the chance of recovery with conservative management. The 3D FSPGR sequence of MRI can be successfully used for detection of the endplate lesions in the herniated disc.

Biomechanical, cadaveric study.

To compare the relative stiffness of unilateral C1 lateral mass-C2 intralaminar fixation to intact specimens and bilateral C1 lateral mass-C2 intralaminar constructs.

The biomechanical integrity of a unilateral C1 lateral mass-C2 intralaminar screw construct was compared to intact specimens and bilateral C1 lateral mass-C2 intralaminar screw constructs. Five human cadaveric specimens were used. Range of motion and stiffness were tested to determine the stiffness of the constructs.

Unilateral fixation significantly decreased flexion/extension range of motion compared to intact (P < .001) but did not significantly affect axial rotation (P = .3) or bending range of motion (P = .3). There was a significant decrease in stiffness in extension for both unilateral and bilateral fixation techniques compared to intact (P = .04 and P = .03, respectively). There was also a significant decrease in stiffness for ipsilateral rotation for the unilateral construct compared to intact (P = .007) whereas the bilateral construct significantly increased ipsilateral rotation stiffness compared to both intact and unilateral fixation (P < .001).

Bilateral constructs did show improved biomechanical properties compared to the unilateral constructs. However, unilateral C1-C2 fixation using a C1 lateral mass and C2 intralaminar screw-rod construct decreased range of motion and improved stiffness compared to the intact state with the exception of extension and ipsilateral rotation. Hence, a unilateral construct may be acceptable in clinical situations in which bilateral fixation is not possible, but an external orthosis may be necessary to achieve a fusion.

Prospective study.

Investigate factors associated with preoperative motor paresis, recovery, ambulatory status, and intraoperative neurophysiological monitoring (IONM) among patients with no preoperative paresis (N group), complete preoperative motor recovery (CR group), and no complete recovery (NCR group) in patients with intramedullary spinal cavernous hemangioma to determine the optimal timing of surgery.

The study evaluated 41 surgical cases in our institute. Disease duration, tumor lesion, manual muscle testing (MMT), and gait at onset, just before surgery, and final follow-up (FU), tumor and lesion volume, IONM, extent of tumor resection, and tumor recurrence were evaluated among N, CR, and NCR groups.

Motor paresis at onset was found in 26 patients (63%), with 42% of those in CR group. Disease duration from onset negatively affected stable gait just before surgery and FU as well as lower preoperative MMT (P < .05). Thoracic tumors were associated with patients with unstable gait before surgery (P < .05). Tumor volume was larger in NCR group (P < .05). IONM significantly decreased in NCR and CR groups than in N group (P < .05). The NCR group had residual mild motor paresis at FU (P < .05). Stable gait at FU was similar in N group and CR group, though lower in NCR group (P < .05).

Early surgery is generally recommended for thoracic tumors and large tumors during stable gait without motor paresis before long disease duration. Surgery may be postponed until patients recover from preoperative motor paresis to allow optimal surgical outcome. IONM should be carefully monitored in patients with a history of preoperative paresis even with preoperative complete motor recovery.

Retrospective study.

To compare 2 methods of selecting the lowest instrumented vertebra (LIV) on the rates of revision surgery for distal junctional kyphosis (DJK) following treatment for Scheuermann’s kyphosis (SK).

A retrospective review of patients who have undergone surgical treatment for SK was performed. Forty-four patients were divided into 2 groups based on intervention: Group 1 (n = 26) included patients who had an LIV distal to or at the sagittal stable vertebrae (SSV), and Group 2 (n = 18) included patients who had an LIV proximal to the SSV. For each group, demographic, radiographic, and revision surgery data was analyzed.

The average follow-up was 3.1 years. There were no differences among demographic variables between the groups. Preoperative and postoperative thoracic kyphosis, lumbar lordosis, and sagittal balance were not different between groups. Postoperatively, Group 1 demonstrated a significantly greater average lordotic disc angle below the LIV compared with Group 2 (Group 1, −6.2 ± 4.3° vs Group 2, −2.9 ± 5.8°; P = .02). In a subgroup analysis, extending fusions to the sagittal stable vertebra rather than the first lordotic disc resulted in fewer distal LIV complications necessitating revision surgery compared with fusing short of the SSV (5% vs 36.3%, P = .04).

The SSV method may reduce complications secondary to distal junctional failure, but at the expense of incorporating additional motion segments in a typically young population.

Retrospective study.

Spinal metastasis can produce pain, deformity, neurological compromise and can decrease life expectancy. Surgical management is usually indicated for pain control, neurological decompression, and to avoid deformity progression. Tokuhashi et al created a scoring system to estimate survival and stratify surgical treatment based on established parameters. Our objective was to evaluate the usefulness of Tokuhashi scoring (TS) system by comparing the predicted and real survival times and analyze the survival time according to the type of tumor.

From 2004 to 2014, 105 patients with vertebral metastasis who underwent surgical treatment were enrolled and retrospectively analyzed. Preoperative TS was performed in all cases. Patients were classified into 3 groups according to TS; group 1 (TS 0-8), group 2 (TS 9-11), and group 3 (TS 12-15). Patients’ average age was 61.5 years, main primary tumor site were as follows: kidney (23%), lung (19%), and breast (18%).

The Tokuhashi general concordance was 67.6%. Per group concordance was as follows: group 1 80%, in group 2, only 33% of concordance was observed. In group 3, 100% of concordance was observed. In group 2, the most common primary sites were breast and kidney and the mean survival was 20 and 22.3 months, respectively, both longer than that expected for this group.

Tokuhashi concordance was acceptable in our study, particularly in lower and higher scores. The lesser concordance observed in group 2 (33.3%) was observed in almost all tumors. For our practice, TS constitutes an acceptable tool to define survival, particularly in lower and higher scores.

Retrospective radiographic study.

The optimal radiographic modality for assessing cervical foraminal stenosis is unclear. Determination on conventional axial cuts is made difficult due in part to the complex, oblique orientation of the cervical neuroforamen. The utility of 3-dimensonal (3D) computed tomography (CT) reconstruction in improving neuroforaminal assessment is not well understood. The objective of this study is to determine inter-rater variability in grading cervical foraminal stenosis using 3 different CT imaging modalities: 3D CT surface reconstructions (3DSR), 2D sagittal oblique multiplanar reformations (2D-SOMPR), and conventional 2D axial CT imaging.

Pretreatment CT scans of 25 patients undergoing surgery for cervical spondylotic radiculopathy were analyzed at 2 levels: C5-C6 and C6-C7. Simple interrater agreement and kappa-Fleiss coefficients were calculated for each imaging modality and stenosis grade. Image reviewers (attending spine surgeon, attending neuroradiologist, spine fellow) interpreted each CT scan in 3 different formats: axial, 2D-SOMPR, and 3DSR. Four cervical foramina at 2 spinal levels were graded as normal (no stenosis), mild (≤25% stenosis), moderate (25%-50% stenosis), or severe (>50% stenosis).

Across all imaging modalities, interrater reliability was fair when grading foraminal stenosis (κ < 0.4). Agreement was lowest for the axial images (κ = 0.119) and highest for the 3D CT reconstructions (κ = 0.334). 2D-SOMPR images also led to improved interrater reliability when compared with axial images (κ = 0.255).

Grading cervical foraminal stenosis using conventional axial CT imaging is difficult with low interrater reliability. CT modalities that provide a circumferential view of the cervical foramen, such as 2D-SOMPR and 3D CT reconstruction, had higher rates of interobserver reliability in grading foraminal stenosis than conventional axial cuts, with 3D having the highest. As these 3D reconstructions can be obtained at no additional cost or radiation exposure over a conventional CT scan, and because they can provide useful information in determining levels being considered for surgical decompression, we recommend they be utilized when evaluating cervical foramina.

Narrative review.

Metastatic spinal cord compression (MSCC) is a very frequent complication among cancer patients. Presenting commonly as nocturnal back pain, MSCC typically progresses to lower extremity paresis, loss of ambulatory capabilities, and paraplegia. In addition to standard treatment modalities, corticosteroid administration has been utilized in preclinical and clinical settings as adjunctive therapy to reduce local spinal cord edema and improve clinical symptoms. This article serves as a review of existing literature regarding corticosteroid management of MSCC and seeks to provide potential avenues of research on the topic.

A literature search was performed using PubMed in order to consolidate existing information regarding dexamethasone treatment of MSCC. Of all search results, 7 articles are reviewed, establishing the current understanding of metastatic spine disease and dexamethasone treatment in both animal models and in clinical trials.

Treatment with high-dose corticosteroids is associated with an increased rate of potentially serious systemic side effects. For this reason, definitive guidelines for the use of dexamethasone in the management of MSCC are unavailable.

It is still unclear what role dexamethasone plays in the treatment of MSCC. It is evident that new, more localizable therapies may provide more acceptable treatment strategies using corticosteroids. Looking forward, the potential for more targeted, localized application of the steroid through the use of nanotechnology would decrease the incidence of adverse effects while maintaining the drug’s efficacy.

Broad narrative review.

To review the evolution, operative technique, outcomes, and complications associated with posterior vertebral column resection.

A literature review of posterior vertebral column resection was performed. The authors’ surgical technique is outlined in detail. The authors’ experience and the literature regarding vertebral column resection are discussed at length.

Treatment of severe, rigid coronal and/or sagittal malalignment with posterior vertebral column resection results in approximately 50–70% correction depending on the type of deformity. Surgical site infection rates range from 2.9% to 9.7%. Transient and permanent neurologic injury rates range from 0% to 13.8% and 0% to 6.3%, respectively. Although there are significant variations in EBL throughout the literature, it can be minimized by utilizing tranexamic acid intraoperatively.

The ability to correct a rigid deformity in the spine relies on osteotomies. Each osteotomy is associated with a particular magnitude of correction at a single level. Posterior vertebral column resection is the most powerful posterior osteotomy method providing a successful correction of fixed complex deformities. Despite meticulous surgical technique and precision, this robust osteotomy technique can be associated with significant morbidity even in the most experienced hands.