The American Journal of Sports Medicine

The tibial tubercle to trochlear groove (TT-TG) distance is often utilized for determining the surgical treatment for patients with patellar instability (PI). It is thought to directly represent the position of the TT on the tibia. Recent work has shown that the measurement of the TT-TG distance is multifactorial.

To investigate the relationship between relative tibial external rotation (rTER) and trochlear dysplasia (TD), as well as the location of the TG and TT in patients with and without PI, and to correlate these and other anatomic measurements with the TT-TG distance.

Cross-sectional study; Level of evidence, 3.

A total of 89 patients with PI who underwent magnetic resonance imaging were identified with 92 matched control patients. A standardized measurement protocol on axial magnetic resonance imaging determined rTER, the proximal and distal TG lateralization (pTGL and dTGL, respectively) ratios, and the TT lateralization (TTL) ratio. Other measures of interest included the lateral trochlear inclination angle, sulcus angle, and lateral patellar inclination angle. Univariate regression was used to determine the associations of TD (lateral trochlear inclination angle, sulcus angle) with rTER and the TG position, and multivariate regression was used to model associations among all the variables with the proximal and distal TT-TG distances.

rTER was significantly higher in the study group (P < .001), and univariate regression showed a significant association between dysplasia measures and rTER (P < .001). The pTGL ratio was lower in the study group (P = .025), but there was no difference in the dTGL ratio (P = .090) or the TTL ratio (P = .098) between the groups. There were no associations between dysplasia measures and the pTGL and dTGL ratios (P > .05). Multivariate regression showed that the proximal TT-TG distance is predicted by the sulcus angle, pTGL ratio, rTER, and TTL ratio (P < .05) and that the distal TT-TG distance is predicted by the lateral patellar inclination angle, dTGL ratio, sulcus angle, rTER, and TTL ratio (P < .05).

rTER had a significant association with TD. The position of the proximal TG was more medial in patients with PI. There was no significant difference in the TTL ratio between patients with and without PI. The TT-TG distance was associated with multiple anatomic measures and was not solely predicated on the position of the TT.

Tibial tubercle–trochlear groove (TT-TG) distance is a risk factor for recurrent patellar dislocation and is often included in algorithmic treatment of instability. The underlying factors that determine TT-TG have yet to be clearly described in orthopaedic literature.

The purpose of our study was to determine the underlying anatomic factors contributing to TT-TG distance. We hypothesized that degree of tubercle lateralization and knee rotation angle may substantially predict TT-TG.

Cross-sectional study; Level of evidence, 3.

All patients evaluated for patellar instability at a single institution between 2013 and 2021 were included. Patients with previous knee osseous procedures were excluded. TT-TG and its anatomic relationship to patellofemoral measures, including dysplasia, femoral anteversion, tibial tubercle lateralization, knee rotation angle, and tibial torsion, were measured and subsequently quantified using univariate and multivariable analysis.

In total, 76 patients met the inclusion criteria (46 female, 30 male; mean ± SD age, 20.6 ± 8.6 years) and were evaluated. Mean TT-TG was 16.2 ± 5.4 mm. On univariate analysis, increasing knee rotation angle (P < .01), tibial tubercle lateralization (P = .02), and tibial torsion (P = .01) were associated with increased TT-TG. In dysplastic cases, patients without medial hypoplasia (Dejour A or B) demonstrated significantly increased TT-TG (18.1 ± 5.4 mm) as compared with those with medial hypoplasia (Dejour C or D; TT-TG: 14.9 ± 5.2 mm; P = .02). Multivariable analysis revealed that increased knee rotation angle (+0.43-mm TT-TG per degree; P < .01) and tubercle lateralization (+0.19-mm TT-TG per percentage lateralization; P < .01) were statistically significant determinants of increased TT-TG distance. Upon accounting for these factors, tibial torsion, trochlear width, and medial hypoplasia were no longer significant components in predicting TT-TG (P≥ .54). Of note, all patients with TT-TG ≥20 mm had tibial tubercle lateralization ≥68%, a knee rotation angle ≥5.8°, or both factors concurrently.

TT-TG distance is most influenced by knee rotation angle and tibial tubercle lateralization.

Tibial eminence fractures are bony avulsions of the anterior cruciate ligament from its insertion on the intercondylar eminence. Numerous anatomic factors have been associated with anterior cruciate ligament injuries, such as posterior tibial slope, but there are few studies evaluating the association with tibial eminence fracture.

To compare posterior tibial slope of pediatric patients with and without tibial eminence fractures. We hypothesized that a steeper posterior tibial slope would be associated with tibial eminence fracture.

Cohort study; Level of evidence, 3.

Patients who underwent surgical treatment of tibial eminence fracture were retrospectively identified between January 2000 and July 2021. Adults aged >20 years and those without adequate imaging were excluded. Controls without gross ligamentous or osseous pathology were identified. Descriptive information and Meyers and McKeever classification were recorded. Posterior tibial slope measurements were obtained by 2 independent orthopaedic surgeons twice, with measurements separated by 3 weeks. Chi-square tests and independent-samples t tests were used to compare posterior tibial slope and patient characteristics. Inter- and intrareviewer variability was determined via the intraclass correlation coefficient.

A total of 51 patients with tibial eminence fractures and 57 controls were included. By sex, tibial eminence fractures occurred among 34 male and 17 female patients with a mean age of 10.9 years. The posterior tibial slope among those with tibial eminence fractures (9.7°) was not significantly greater than that of controls (8.8°; P = .07). Male patients with a tibial eminence fracture had significantly steeper slopes compared with controls (10.0° vs 8.4°; P = .006); this difference was not observed between female patients and female controls. Patients with a slope ≥1 SD above the mean (12.0°) had 3.8 times greater odds (95% CI, 1.3-11.6; P = .017) of having a tibial eminence fracture. Male patients with a posterior tibial slope >12° had 5.8 times greater odds (95% CI, 1.1-29.1; P = .034) of having a tibial eminence fracture compared with male controls.

Male patients undergoing surgical fixation of a tibial eminence fracture had an increased posterior tibial slope as compared with case-controls. Increased posterior tibial slope may be a risk factor for sustaining a tibial eminence fracture, although the clinical significance of this deserves further investigation.

Elevated posterior tibial slope (PTS) has been identified as an important risk factor in anterior cruciate ligament (ACL) injuries and ACL graft failures. The cutoff value to recommend treatment with slope-reducing osteotomy remains unclear and is based on expert opinion and small case series.

(1) To determine whether there is a difference in PTS shown on lateral knee radiographs and magnetic resonance imaging (MRI) scans in a group of patients who experienced revision ACL graft failure versus a control group of patients who underwent successful revision ACL reconstruction, (2) to identify cutoff values of PTS measurements that predict risk of revision ACL graft failure, and (3) to examine whether there is a correlation between radiographic and MRI measurements of PTS.

Case-control study; Level of evidence, 3.

A total of 38 patients who experienced revision ACL graft failure were identified from a revision ACL database. These patients were matched 1:1 by age, sex, and graft type to a group of 38 control patients who underwent revision ACL reconstruction with no evidence of graft failure at a minimum 2 years of follow-up. Medial and lateral PTS were measured by lateral knee radiographs and MRI scans of the affected limb. Demographics, surgical characteristics, and PTS were compared between the groups. The optimal cutoff values of medial and lateral PTS per radiographs and MRI scans for predicting increased risk of revision ACL graft failure were determined by receiver operating characteristic curves. Conditional multivariable logistic regression was used to assess the relative contribution of PTS cutoff values as a predictor of revision graft failure.

The mean PTS values in the failure group were significantly higher than those in the control group on radiographs (medial, 13.2°± 2.9° vs 10.3°± 2.9°; P < .001; lateral, 12.9°± 3.0° vs 9.8°± 2.8°; P < .001) and MRI scans (medial, 7.2°± 3.1° vs 4.8°± 2.9°; P < .001; lateral, 8.4 ± 3.1° vs 5.9 ± 3.0°; P < .001). A radiographic medial PTS ≥14° had the highest increased risk of revision ACL graft failure with sensitivity equal to 50% and specificity to 92.1% (odds ratio, 18.71; 95% CI, 2.0-174.9; P = .01).

Elevated PTS was a significant risk factor for revision ACL graft failure. Patients with radiographic medial PTS ≥14° had 18.7-times increased risk of revision ACL failure.

Anterior cruciate ligament (ACL) revision surgery is challenging for both patients and surgeons. Understanding the risk factors for failure after bridge-enhanced ACL restoration (BEAR) may help with patient selection for ACL restoration versus ACL reconstruction.

To identify the preoperative risk factors for ACL revision surgery within the first 2 years after BEAR.

Case-control study; Level of evidence, 3.

Data from the prospective BEAR I, II, and III trials were used to determine the preoperative risk factors for ACL revision surgery. All patients with a complete ACL tear (aged 13-47 years, depending on the trial), who met all other inclusion/exclusion criteria and underwent a primary BEAR procedure within 30 to 50 days from the injury (dependent on the trial), were included. Demographic data (age, sex, body mass index), baseline patient-reported outcomes (International Knee Documentation Committee [IKDC] subjective score, Marx activity score), preoperative imaging results (ACL stump length, notch size, tibial slope), and intraoperative findings (knee hyperextension, meniscal status) were evaluated to determine their contribution to the risk of ipsilateral ACL revision surgery.

A total of 123 patients, with a median age of 17.6 years (interquartile range, 16-23 years), including 67 (54%) female patients, met study criteria. Overall, 18 (15%) patients required ACL revision surgery in the first 2 years after the BEAR procedure. On bivariate analyses, younger age (P = .011), having a contact injury at the time of the initial tear (P = .048), and increased medial tibial slope (MTS; P = .029) were associated with a higher risk of ipsilateral revision surgery. Multivariable logistic regression analyses identified 2 independent predictors of revision: patient age and MTS. The odds of ipsilateral revision surgery were decreased by 32% for each 1-year increase in age (odds ratio, 0.684 [95% CI, 0.517-0.905]; P = .008) and increased by 28% for each 1° increase in MTS (odds ratio, 1.280 [95% CI, 1.024-1.601]; P = .030). Sex, baseline IKDC or Marx score, knee hyperextension, and meniscal status were not significant predictors of revision.

Younger age and higher MTS were predictors of ipsilateral ACL revision surgery after the BEAR procedure. Younger patients with higher tibial slopes should be aware of the increased risk for revision surgery when deciding to undergo ACL restoration.

Bone bruises observed on magnetic resonance imaging (MRI) can provide insight into the mechanisms of noncontact anterior cruciate ligament (ACL) injury. However, it remains unclear whether the position of the knee near the time of injury differs between patients evaluated with different patterns of bone bruising, particularly with regard to valgus angles.

The position of the knee near the time of injury is similar between patients evaluated with 2 commonly occurring patterns of bone bruising.

Descriptive laboratory study.

Clinical T2- and T1-weighted MRI scans obtained within 6 weeks of noncontact ACL rupture were reviewed. Patients had either 3 (n = 20) or 4 (n = 30) bone bruises. Patients in the 4–bone bruise group had bruising of the medial and lateral compartments of the femur and tibia, whereas patients in the 3–bone bruise group did not have a bruise on the medial femoral condyle. The outer contours of the bones and associated bruises were segmented from the MRI scans and used to create 3-dimensional surface models. For each patient, the position of the knee near the time of injury was predicted by moving the tibial model relative to the femoral model to maximize the overlap of the tibiofemoral bone bruises. Logistic regressions (adjusted for sex, age, and presence of medial collateral ligament injury) were used to assess relationships between predicted injury position (quantified in terms of knee flexion angle, valgus angle, internal rotation angle, and anterior tibial translation) and bone bruise group.

The predicted injury position for patients in both groups involved a flexion angle <20°, anterior translation >20 mm, valgus angle <10°, and internal rotation angle <10°. The injury position for the 3–bone bruise group involved less flexion (odds ratio [OR], 0.914; 95% CI, 0.846-0.987; P = .02) and internal rotation (OR, 0.832; 95% CI, 0.739-0.937; P = .002) as compared with patients with 4 bone bruises.

The predicted position of injury for patients displaying both 3 and 4 bone bruises involved substantial anterior tibial translation (>20 mm), with the knee in a straight position in both the sagittal (<20°) and the coronal (<10°) planes.

Landing on a straight knee with subsequent anterior tibial translation is a potential mechanism of noncontact ACL injury.

Stem cell sheets provide a scaffold-free option for the promotion of graft healing after anterior cruciate ligament reconstruction (ACLR). However, cell viability, stability, and potential uncontrolled actions create challenges for clinical translation. The decellularization of cell sheets may overcome these problems as studies have shown that the natural extracellular matrix of stem cells is bioactive and can promote tissue repair.

The decellularized tendon-derived stem cell (dTDSC) sheet can promote graft healing after ACLR.

Controlled laboratory study.

An optimized decellularization protocol was developed to decellularize the TDSC sheets. A total of 64 Sprague-Dawley rats underwent ACLR with or without the dTDSC sheet wrapping the tendon graft (n = 32/group). At 2 and 6 weeks after surgery, graft healing was assessed by micro–computed tomography, histology, and biomechanical testing. The accumulation of iNOS⁺ and CD206⁺ cells and the expression of metalloproteinase 1 (MMP-1), MMP-13, and tissue inhibitor of metalloprotease 1 (TIMP-1) were assessed by immunohistochemistry.

The decellularization was successful, with the removal of 98.4% nucleic acid while preserving the collagenous proteins and bioactive factors. The expression of bone morphogenetic protein 2 (BMP-2) and VEGF in the dTDSC sheet was comparable with the TDSC sheet (P > .05). Micro–computed tomography showed significantly more tunnel bone formation in the dTDSC sheet group. The dTDSC sheet group demonstrated better graft osteointegration and higher integrity of graft midsubstance with significantly higher ultimate failure load (16.58 ± 7.24 vs 8.93 ± 2.45 N; P = .002) and stiffness (11.97 ± 5.21 vs 6.73 ± 2.20 N/mm; P = .027). Significantly fewer iNOS⁺ cells but more CD206⁺ cells, as well as lower MMP-1 and MMP-13 but higher TIMP-1 expression, were detected at the tendon-bone interface and graft midsubstance in the dTDSC sheet group.

An optimized decellularization protocol for producing bioactive dTDSC sheets was developed. Wrapping tendon graft with a dTDSC sheet promoted graft healing after ACLR, likely via enhancing bone formation and angiogenesis by BMP-2 and VEGF, modulating macrophage polarization and MMP/TIMP expression, and physically protecting the tendon graft.

dTDSC sheets alleviate the quality control and safety concerns of cell transplantation and can be used as a cell-free alternative for the promotion of graft healing in ACLR.

Anterior cruciate ligament (ACL) tear (ACLT) leads to protracted quadriceps muscle atrophy. Protein turnover largely dictates muscle size and is highly responsive to injury and loading. Regulation of quadriceps molecular protein synthetic machinery after ACLT has largely been unexplored, limiting development of targeted therapies.

To define the effect of ACLT on (1) the activation of protein synthetic and catabolic signaling within quadriceps biopsy specimens from human participants and (2) the time course of alterations to protein synthesis and its molecular regulation in a mouse ACL injury model.

Descriptive laboratory study.

Muscle biopsy specimens were obtained from the ACL-injured and noninjured vastus lateralis of young adult humans after an overnight fast (N = 21; mean ± SD, 19 ± 5 years). Mice had their limbs assigned to ACLT or control, and whole quadriceps were collected 6 hours or 1, 3, or 7 days after injury with puromycin injected before tissue collection for assessment of relative protein synthesis. Muscle fiber size and expression and phosphorylation of protein anabolic and catabolic signaling proteins were assessed at the protein and transcript levels (RNA sequencing).

Human quadriceps showed reduced phosphorylation of ribosomal protein S6 (–41%) in the ACL-injured limb (P = .008), in addition to elevated phosphorylation of eukaryotic initiation factor 2α (+98%; P = .006), indicative of depressed protein anabolic signaling in the injured limb. No differences in E3 ubiquitin ligase expression were noted. Protein synthesis was lower at 1 day (P = .01 vs control limb) and 3 days (P = .002 vs control limb) after ACLT in mice. Pathway analyses revealed shared molecular alterations between human and mouse quadriceps after ACLT.

(1) Global protein synthesis and anabolic signaling deficits occur in the quadriceps in response to ACL injury, without notable changes in measured markers of muscle protein catabolism. (2) Importantly, these deficits occur before the onset of significant atrophy, underscoring the need for early intervention.

These findings suggest that blunted protein anabolism as opposed to increased catabolism likely mediates quadriceps atrophy after ACL injury. Thus, future interventions should aim to restore muscle protein anabolism rapidly after ACLT.

Anterior cruciate ligament reconstruction (ACLR) is a commonly performed orthopaedic procedure. The volume and cost of ACLR procedures are increasing annually, but the drivers of these cost increases are not well described.

To analyze the modifiable drivers of total health care utilization (THU), immediate procedure reimbursement, and surgeon reimbursement for patients undergoing ACLR using a large national commercial insurance database from 2013 to 2017.

Descriptive epidemiology study.

For this study, the cohort consisted of patients identified in the MarketScan Commercial Claims and Encounters database who underwent outpatient arthroscopic ACLR in the United States from 2013 to 2017. Patients with Current Procedural Terminology code 29888 were included. THU was defined as the sum of any payment related to the ACLR procedure from 90 days preoperatively to 180 days postoperatively. A multivariable model was utilized to describe the patient- and procedure-related drivers of THU, immediate procedure reimbursement, and surgeon reimbursement.

There were 34,862 patients identified. On multivariable analysis, the main driver of THU and immediate procedure reimbursement was an outpatient hospital as the surgical setting (US$6789 increase in THU). The main driver of surgeon reimbursement was an out-of-network surgeon (US$1337 increase). Health maintenance organization as the insurance plan type decreased THU, immediate procedure reimbursement, and surgeon reimbursement (US$955, US$108, and US$38 decrease, respectively, compared with preferred provider organization; P < .05 for all).

Performing procedures in more cost-efficient ambulatory surgery centers had the largest effect on decreasing health care expenditures for ACLR. Health maintenance organizations aided in cost-optimization efforts as well, but had a minor effect on surgeon reimbursement. Overall, this study increases transparency into what drives reimbursement and serves as a foundation for how to decrease health care expenditures related to ACLR.

Peripheral tears of the posterior horn of the medial meniscus, known as “ramp lesions,” are commonly found in anterior cruciate ligament (ACL)–deficient knees but are frequently missed on routine evaluation.

To predict the presence of ramp lesions in ACL-deficient knees using machine learning methods with associated risk factors.

Cohort study (Diagnosis); Level of evidence, 2.

This study included 362 patients who underwent ACL reconstruction between June 2010 and March 2019. The exclusion criteria were combined fractures and multiple ligament injuries, except for medial collateral ligament injuries. Patients were grouped according to the presence of ramp lesions on arthroscopic surgery. Binary logistic regression was used to analyze risk factors including age, sex, body mass index, time from injury to surgery (≥3 or <3 months), mechanism of injury (contact or noncontact), side-to-side laxity, pivot-shift grade, medial and lateral tibial/meniscal slope, location of bone contusion, mechanical axis angle, and lateral femoral condyle (LFC) ratio. The receiver operating characteristic curve and area under the curve were also evaluated.

Ramp lesions were identified in 112 patients (30.9%). The risk for ramp lesions increased with steeper medial tibial and meniscal slopes, higher knee laxity, and an increased LFC ratio. Comparing the final performance of all models, the random forest model yielded the best performance (area under the curve: 0.944), although there were no significant differences among the models (P > .05). The cut-off values for the presence of ramp lesions on receiver operating characteristic analysis were as follows: medial tibial slope >5.5° (P < .001), medial meniscal slope >5.0° (P < .001), and LFC ratio >71.3% (P = .033).

Steep medial tibial and meniscal slopes, an increased LFC ratio, and higher knee rotatory laxity were observed risk factors for ramp lesions in patients with an ACL injury. The prediction model of this study could be used as a supplementary diagnostic tool for ramp lesions in ACL-injured knees. In general, care should be taken in patients with ramp lesions and its risk factors during ACL reconstruction.

Meniscal allograft transplant (MAT) is an effective treatment for relieving symptoms and improving knee function in patients who experience symptomatic unicompartmental knee pain after a previous meniscectomy. However, the literature contains a paucity of studies assessing the survival rate and prognostic factors of soft tissue MAT.

To report the survivorship of a large, single-center cohort of consecutive patients treated with arthroscopic MAT using soft tissue technique and to investigate variables that could potentially influence failures and outcomes.

Case series; Level of evidence, 4.

Consecutive MAT procedures totaling 364 performed in a single institution between June 2004 and April 2019 were screened and assessed for eligibility. Subjective clinical scores (Lysholm score, Tegner activity scale, and visual analog score) were collected preoperatively and at 2, 5, 7, and 10 years of follow-up. Two survival analyses were performed using Kaplan-Meier curves, with surgical failure (defined as any graft revision) and clinical failure (defined as a Lysholm score <65 points) used as endpoints. Univariate analyses were performed using reoperations, surgical failure, clinical failure, and different demographic and surgical characteristics as endpoints.

A total of 324 consecutive patients were evaluated at a mean follow-up 5.7 ± 3.0 years. Of these, 189 (58%) underwent an associated surgical procedure. A total of 22 patients (6.8%) were considered to have experienced surgical failure, and no predictors of surgical failure were identified based on the relevant variables. When all patients were considered, a significant improvement in all of the patient-reported outcome measures was present between the preoperative assessment and the last follow-up (P < .001), with no significant decrease over time. Moreover, 70 (21.6%) patients were considered to have experienced clinical failure; the need for concurrent cartilage procedures (odds ratio, 0.16; P = .001) and anterior cruciate ligament (ACL) reconstruction (odds ratio, 0.40; P = .059) were predictors of failure. Finally, a lower survival rate was reported in female patients compared with male patients (49% vs 69%, respectively; P = .007) and in patients who required cartilage surgery (P = .014). In particular, patients who required cartilage surgery showed nearly half the survival rate compared with those with required no cartilage procedures at 10-year follow-up (36.4% vs 71%, respectively; P = .029).

Female sex and the need to combine MAT with a cartilage procedure or ACL reconstruction could result in an increased rate of clinical failure at midterm follow-up.

Identification of morphological risk factors associated with the knee that threaten ligaments is important for understanding injury mechanisms and prevention. However, the morphological risk factors for posterior cruciate ligament (PCL) lesions are not clearly understood.

To investigate whether the medial tibial depth (MTD), medial and lateral posterior tibial slope, asymmetry of the medial and lateral slopes, radius of the sagittal plane medial femoral condyle, coronal tibial slope, and notch width index (NWI) were risk factors for PCL intrasubstance tearing (PCLIT) and tibial avulsion fractures (PCLAF).

Cross-sectional study; Level of evidence, 3.

Between January 2015 and March 2022, 82 patients with isolated PCLIT, 68 patients with isolated PCLAF, and 82 controls without any ligamentous or meniscal pathologic findings as determined via physical examination and magnetic resonance imaging were included. Values were compared among the 3 groups. Logistic regression analysis was performed to confirm the risk factors. Receiver operating characteristic curves were defined for the morphological indicators and combination of risk factors.

Logistic regression analysis revealed (1) MTD, lateral minus medial posterior tibial slope, radius of the posterior circle of the medial femoral condyle, and NWI as significant independent predictors for PCLIT and (2) MTD and NWI for PCLAF. The areas under the curve combining the 4 indicators for PCLIT and noncontact PCLIT were 0.79 (95% CI, 0.72-0.86) and 0.90 (95% CI, 0.85-0.96), respectively. The area under the curve for the combination of MTD and NWI for PCLAF was 0.78 (95% CI, 0.70-0.86).

Decreased MTD and NWI were associated with an increased incidence of PCLIT and PCLAF. Increased asymmetry of the medial and lateral slopes and the radius of the posterior circle of the medial femoral condyle were associated with the presence of PCLIT. In addition, the model of a combination of risk factors showed good predictive ability for noncontact PCLIT. These findings may aid clinicians in identifying patients at risk for PCL lesions. Further studies are warranted for identifying the effect of these factors on biomechanical mechanisms.

Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life.

To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome.

Cohort study; Level of evidence, 2.

Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change.

A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (β = −0.82; P = .034), access to private health care (β = 12.91; P = .013), and worse baseline iHOT-33 score (β = −0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (β = −24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively).

No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

Previous studies have demonstrated various groin-related nerve and soft tissue complications in patients undergoing hip arthroscopy with a perineal post.

To prospectively compare groin-related nerve and soft tissue complications between patients undergoing hip arthroscopy with and without the use of a perineal post.

Cohort study; Level of evidence, 2.

A prospective single-surgeon cohort study was performed on all patients undergoing hip arthroscopy by the senior author between January 2020 and March 2022. A post-free hip distraction system was used at 1 center in which the senior author operates, and a system with a large padded perineal post was used at another surgical location. Patients completed a survey at the first postoperative visit (7-10 days) to determine if they had experienced any groin-related complications after surgery (groin numbness, sexual/urinary dysfunction, skin tears). Patients with a positive survey response repeated the survey at each follow-up visit (6 weeks, 3 months, 6 months) until the symptoms resolved. The rate and duration of groin-related complications were then compared between the groups.

A total of 87 patients were included in the study who underwent hip arthroscopy: 53 with a perineal post and 34 without. No differences were found between the post and postless groups in terms of age at surgery, sex, body mass index, or traction time. We found that 16 patients (30%) in the perineal post group experienced groin numbness versus 0 (0%) in the postless group (P < .0001). On average, groin numbness lasted 5 ± 3 days (mean ± SD) in the perineal post group. Three patients in the perineal post group experienced sexual dysfunction for a mean 7 days, as compared with none in the postless group. Seventeen patients (32%) in the perineal post group experienced foot numbness versus 4 (12%) in the postless group (P = .04). One patient in the perineal post group reported a superficial skin tear.

Postless hip arthroscopy resulted in no risk of groin-related complications as compared with traditional hip arthroscopy with a perineal post.

The best treatment of degenerative hip abductor tendon lesions remains largely unknown, as the natural course of the disease has not yet been reported. The aim of the present study was to investigate the natural history of symptomatic degenerative hip abductor lesions.

Nonoperatively treated hip abductor lesions progress over time, resulting in refractory hip pain and low functional outcomes.

Case series (prognosis); Level of evidence, 4.

Consecutive patients with greater trochanteric pain syndrome and degenerative changes on magnetic resonance imaging (MRI) of the symptomatic hip were included. Bilateral hip MRI scans and a clinical examination were performed at a minimum follow-up of 36 months to study the type and location of hip abductor lesion. Progression of a lesion was defined as a more severe lesion as compared with the initial MRI results or if the lesion extended to another, initially not involved, trochanteric facet. The muscle’s fatty infiltration (FI) was also described.

From 106 patients identified, 58 patients (64 hips) aged 66 ± 14 years (mean ± SD) agreed to return to the clinic for follow-up MRI and met the inclusion criteria. At a mean 71-month follow-up, an overall 34% (22/64) of lesions had progressed over time: from trochanteric bursitis to tendinopathy (9/64, 14%) or partial tear (5/64, 8%), from tendinopathy to partial tear (4/64, 6%), from a partial to complete tear (3/64, 4.5%), and with 1 complete tear (1/64, 1.5%) extending to another trochanteric facet. Interestingly, 90% of partial tears remained stable or transformed into a scar. Although patients with a progressive lesion experienced more trochanteric pain (visual analog scale, 4.6 vs 2.8; P = .001), the functional outcomes were comparable with patients with a stable lesion. The majority of hips with a partial tear (64%) demonstrated a progression of gluteus minimus FI from a median grade of 1 to 2, whereas only 1 hip (3%) progressed from grade 2 to 3. Only 3 hips (9%) with a partial tear had a progression of gluteus medius FI, which did not differ significantly from the contralateral unaffected side.

Nonoperative treatment might be a valid long-term option for degenerative hip abductor lesions, especially for partial tears, which demonstrated a low risk of clinically relevant progression or muscle FI and similar clinical outcomes to those reported in the literature for operatively treated hip abductor tendon lesions.

Epidemiological studies of lateral ankle sprains in NCAA sports are important in appraising the burden of this injury and informing prevention efforts.

To describe the epidemiology of lateral ankle sprains in NCAA sports during the 2014-15 through 2018-19 seasons.

Descriptive epidemiology study.

Injury and exposure information collected within the NCAA Injury Surveillance Program (ISP) were examined. Counts, rates, and proportions of lateral ankle sprains were used to describe injury incidence by sport, event type (practices, competitions), season segment (preseason, regular season, postseason), injury mechanism (player contact, noncontact, and surface contact, injury history (new, recurrent), and time loss (time loss [≥1 day], non–time loss). Injury rate ratios (IRRs) were used to examine differential injury rates, and injury proportion ratios (IPRs) were used to examine differential distributions.

A total of 3910 lateral ankle sprains were reported (4.61 per 10,000 athlete exposures) during the study period, and the overall rate was highest in men’s basketball (11.82 per 10,000 athlete exposures). The competition-related injury rate was higher than the practice-related rate (IRR, 3.24; 95% CI, 3.04-3.45), and across season segments, the overall rate was highest in preseason (4.99 per 10,000 athlete exposures). Lateral ankle sprains were most often attributed to player-contact mechanisms in men’s (43.2%) and women’s sports (35.1%), although injuries were more prevalently attributed to player contact in men’s than in women’s sports (IPR, 1.23; 95% CI, 1.13-1.34). Overall, 49.7% of all lateral ankle sprains were time loss injuries.

The findings of this study are consistent with previous epidemiological investigations of lateral ankle sprains among NCAA athletes. Results offer additional context on differential injury mechanisms between men’s and women’s sports and on injury risk across the competitive season. Future research may examine the effectiveness of deploying injury prevention programs before the start of a season.

Perioperative education and socioeconomic factors influence patient behavior. Recent evidence has suggested that sling compliance is associated with improved outcomes after shoulder surgery; it is important to investigate factors that influence sling compliance.

To determine the associations between postoperative sling wear and patients’ understanding of sling necessity, postoperative home assistance, and social deprivation.

Cohort study; Level of evidence, 2.

A total of 66 patients were prospectively enrolled from 2018 to 2020 if they were ≥18 years of age and undergoing shoulder surgery requiring a sling for at least 1 month postoperatively. Sling wear was measured using a temperature-sensing device. At 6 weeks postoperatively, patients’ understanding for sling necessity was determined by their response to a question on the Medical Adherence Measure questionnaire, “Why did you have to wear a shoulder sling?” The Patient Understanding Grading Scale (PUGS) was developed to quantify patient responses. PUGS was graded 1 to 3, with grade 1 corresponding to the least technical knowledge. Patient characteristics, social deprivation (Area Deprivation Index [ADI]), and home assistance were additionally analyzed.

There were no significant differences in baseline characteristics between patients when stratified by PUGS grade. Multivariable linear regression analysis for total hours of sling wear per week showed that patients with PUGS grade 2 (β, 48.2 hours; P = .007) and grade 3 (β, 59.5 hours; P = .003) wore their slings significantly more than grade 1 patients. Patients with home assistance had significantly greater day hours (73.5 ± 33.0 vs 44.0 ± 24.5 hours; P = .037) of sling wear per week, but there was no difference in night sling hours. Patients older than 60 years wore their slings significantly more, while men and those with a higher body mass index (BMI) wore their slings significantly less. ADI was not significantly associated with sling wear.

This study demonstrates that patients with greater understanding for sling necessity, those with home assistance, and patients >60 years have greater sling wear, while male patients and those with a higher BMI have lower sling compliance. ADI was not a significant contributor.

As an alternative to the Latarjet procedure, the arthroscopic free bone block (FBB) procedure combined with dynamic anterior stabilization (DAS) has been recently proposed to provide both glenoid augmentation and a tendon sling effect for treating anterior shoulder instability (ASI) with glenoid bone loss.

To evaluate the clinical and radiological outcomes of FBB-DAS for ASI with glenoid bone loss.

Case series; Level of evidence, 4.

Patients who underwent arthroscopic FBB-DAS for ASI with >15% glenoid bone loss between February 2017 and March 2020 were screened and enrolled in this study. Clinical outcome measures were assessed preoperatively and at a minimum 2-year follow-up, including recurrence, complications, shoulder functional scores, range of motion, and return to sports. Postoperative computed tomography and magnetic resonance imaging were also performed.

Of a total of 65 patients with a mean follow-up of 46.1 ± 13.1 months, no patients experienced a recurrent dislocation or subluxation postoperatively, while 2 had a positive anterior apprehension test (3.1%). Additionally, 2 patients (3.1%) experienced complications of hematoma and shoulder stiffness, respectively. The mean visual analog scale score, American Shoulder and Elbow Surgeons score, Rowe score, and Oxford Shoulder Instability Score all improved significantly from 3.2 ± 2.4, 75.0 ± 18.9, 43.6 ± 27.3, and 33.8 ± 9.0 preoperatively to 1.3 ± 0.8, 95.1 ± 8.0, 95.5 ± 7.8, and 14.8 ± 3.5 at final follow-up, respectively (all P < .001). No difference was detected in range of motion except for 8.1° and 7.5° external rotation limitations in adduction and abduction, respectively. There were 62 patients (95.4%) who returned to sports, and 54 patients (83.1%) returned to the preinjury level. The transferred biceps tendon was intact in all 59 patients who completed radiological examination at the latest follow-up. Good bone healing was achieved in 98.3% of patients, and the glenoid bone defect decreased from 18.1% to 4.9%. Osseous and labral glenoids were significantly enlarged in width and depth on the latest magnetic resonance imaging (all P < .001).

Arthroscopic FBB-DAS provided satisfactory clinical and radiological outcomes for ASI with glenoid bone loss. Despite slight external rotation restrictions, it achieved low recurrence and complication rates, excellent shoulder functional scores, a high return-to-sports rate, and favorable graft healing and remodeling.

Loss of initial reduction of the acromioclavicular joint after coracoclavicular (CC) ligament reconstruction remains a challenge for various repair techniques. Previous studies using polydioxanone suture cerclage augments for CC ligament reconstruction demonstrated poor clinical and biomechanical outcomes. Tape-style sutures have recently gained popularity because of their added stiffness and strength relative to traditional sutures. These tape cerclage systems have yet to be biomechanically studied in CC ligament reconstruction.

To determine the efficacy of a tape cerclage system as an augment to CC ligament reconstruction.

Controlled laboratory study.

A total of 24 human cadaveric shoulders were utilized. These were divided into 4 repair groups: anatomic CC ligament reconstruction (ACCR), ACCR with a tape cerclage augment (ACCR + C), tendon graft sling with a cerclage augment (TGS + C), or tape cerclage sling alone (CS). The repairs underwent superior/inferior cyclic loading to evaluate for displacement. Specimens were visually inspected for cortical erosion by the tape cerclage after cyclic loading. Finally, the constructs underwent superior plane load-to-failure testing.

Less displacement after cyclic loading was observed in the ACCR + C (mean ± SD, 0.42 ± 0.32 mm), TGS + C (0.92 ± 0.42 mm), and CS (0.93 ± 0.39 mm) groups as compared with the ACCR group (4.42 ± 3.40 mm; P = .002). ACCR + C (813.3 ± 257.5 N), TGS + C (558.0 ± 120.7 N), and CS (759.5 ± 173.7 N) demonstrated significantly greater load at failure relative to ACCR (329.2 ± 118.2 N) (P < .001). ACCR + C (60.88 ± 17.3 N/mm), TGS + C (44.97 ± 9.15 N/mm), and CS (54.52 ± 14.24 N/mm) conferred greater stiffness than ACCR (27.43 ± 6.94 N/mm) (P = .001). No cortical erosion was demonstrated in any specimen after cyclic loading.

In a cadaveric model at time zero, repairs utilizing a tape cerclage system confer significantly greater load to failure and stiffness, as well as decreased displacement with cyclic loading, when compared with traditional ACCR repair.

Tape cerclage augmentation may provide a useful augment for CC ligament reconstruction.

Medial ulnar collateral ligament (mUCL) reconstructions are becoming increasingly prevalent among the overhand throwing population. Suture tape augmentation has the potential to provide biomechanical advantages over standard docking reconstruction. However, the optimal tensioning of the suture augmentation technique has not yet been evaluated.

To compare the subfailure biomechanical performance and graft strain of a standard docking mUCL reconstruction to an mUCL reconstruction using suture tape augmentation tensioned with 1 mm or 3 mm of laxity.

Controlled laboratory study.

A total of 18 cadaveric elbows were dissected to the mUCL anterior band and biomechanically assessed via a valgus torque protocol to failure. Elbows were randomly assigned to be reconstructed via (1) a standard docking technique, (2) a suture-augmented reconstruction with 1-mm laxity, or (3) a suture-augmented reconstruction with 3-mm laxity. Reconstructed elbows were then subjected to the same loading protocol. Subfailure mechanical properties, failure mode, and mUCL/palmaris strain were assessed.

All reconstruction groups had decreased rotational stiffness, torque at 5° of angular rotation, and resilience compared with matched native controls. There were no differences in transition torque between groups. The failure mode of suture-augmented specimens was most often due to bone tunnel failure or reaching the maximum allowable angular displacement. In native controls or docking reconstructions, the primary failure mechanism was in the ligament or graft midsubstance. There were no significant differences in strain on the reconstructed or suture-augmented groups at any laxity compared with native controls.

Suture augmentation results in similar subfailure joint biomechanical properties as the standard docking reconstruction procedure at both laxity levels in a cadaveric model. There are improvements in the failure mode of suture-augmented specimens compared with standard docking. Graft strain may be modestly reduced in the 1-mm laxity group compared with other reconstruction groups.

Suture augmentation at both 1-mm and 3-mm laxity appears to offer similar advantages in subfailure biomechanics to standard docking reconstruction of the mUCL, with some improvements associated with failure mode. Strain data suggest a potential avoidance of graft stress shielding when tensioning the suture augmentation to 3-mm laxity, which is not as apparent with 1-mm laxity.

Approximately half of concussions go undisclosed and therefore undiagnosed. Among diagnosed concussions, 51% to 64% receive delayed medical care. Understanding the influence of undiagnosed concussions and delayed medical care would inform medical and education practices.

To compare postconcussion longitudinal clinical outcomes among (1) individuals with no concussion history, all previous concussions diagnosed, and ≥1 previous concussion undiagnosed, as well as (2) those who have delayed versus immediate symptom onset, symptom reporting, and removal from activity after concussion.

Cohort study; Level of evidence, 2.

Participants included 2758 military academy cadets and intercollegiate athletes diagnosed with concussion in the CARE Consortium. We determined (1) each participant’s previous concussion diagnosis status self-reported at baseline (no history, all diagnosed, ≥1 undiagnosed) and (2) whether the participant had delayed or immediate symptom onset, symptom reporting, and removal from activity. We compared symptom severities, cognition, balance, and recovery duration at baseline, 24 to 48 hours, date of asymptomatic status, and date of unrestricted return to activity using tests of parallel profiles.

The ≥1 undiagnosed concussion group had higher baseline symptom burdens (P < .001) than the other 2 groups and poorer baseline verbal memory performance (P = .001) than the all diagnosed group; however, they became asymptomatic and returned to activity sooner than those with no history. Cadets/athletes who delayed symptom reporting had higher symptom burdens 24 to 48 hours after injury (mean ± SE; delayed, 28.8 ± 0.8; immediate, 20.6 ± 0.7), took a median difference of 2 days longer to become asymptomatic, and took 3 days longer to return to activity than those who had immediate symptom reporting. For every 30 minutes of continued participation after injury, days to asymptomatic status increased 8.1% (95% CI, 0.3%-16.4%).

Clinicians should expect that cadets/athletes who delay reporting concussion symptoms will have acutely higher symptom burdens and take 2 days longer to become asymptomatic. Educational messaging should emphasize the clinical benefits of seeking immediate care for concussion-like symptoms.

The Post-Concussion Symptom Scale (PCSS) is a self-report questionnaire measuring symptoms that commonly occur after a concussion; however, these symptoms are nonspecific and can be related to co-occurring orthopaedic injuries (eg, cervical strain) or patient characteristics and preexisting conditions, even in the absence of a recent injury. As such, clinicians may have difficulty determining whether symptom elevations are attributable to a recent concussion as opposed to a confounding injury or a preexisting condition, which may be especially difficult when preinjury baseline symptom data are unavailable.

This study aimed to further validate the 4-factor model of the PCSS (ie, cognitive, sleep-arousal, physical, and affective symptoms) with adolescent student-athletes and provide normative reference data for each factor and the total score, stratified by gender and preexisting health conditions.

Cross-sectional study; Level of evidence, 3.

Participants were 9358 adolescent student-athletes who completed the PCSS during a preseason baseline evaluation (mean age, 14.9 years; SD, 1.3 years [range, 13-18 years]; 49.3% boys). The 4-factor model of the PCSS was tested for the full sample and separately for boys and girls using confirmatory factor analysis. Symptom severity percentiles were created for the PCSS total score and each factor, stratified by gender and preexisting conditions (ie, attention-deficit/hyperactivity disorder, mental health history, headache/migraine history, learning disability/dyslexia, academic problems, and concussion history).

The 4-factor model of the PCSS replicated in the full sample (comparative fit index [CFI] = 0.959) and in both gender groups (boys: CFI = 0.961; girls: CFI = 0.960). The total PCSS score at the 84th percentile varied by preexisting conditions as follows: healthy participants = 8, attention-deficit/hyperactivity disorder = 18, mental health history = 26, headache/migraine history = 18, learning disability = 19, and academic problems = 17. On all PCSS subscales, participants with a mental health history had the highest scores, and high scores were associated with having >1 preexisting condition. Girls had higher scores than boys for each stratification.

The 4-factor model of the PCSS replicates for adolescent student-athletes. Gender, number of preexisting conditions, and mental health history are important factors to account for when interpreting PCSS symptom severity. The normative data provided herein could assist clinicians in determining whether an adolescent student-athlete is presenting with persistent postconcussion symptoms or a typical symptom experience based on their gender and personal health history.

Chondrocyte-based cell therapy to repair cartilage has been used for >25 years despite current limitations. This work presents a new treatment option for cartilage lesions.

High-quality hyaline cartilage microtissues called Cartibeads are capable of treating focal chondral lesions once implanted in the defect, by complete fusion of Cartibeads among themselves and their integration with the surrounding native cartilage and subchondral bone.

Controlled laboratory study.

Cartibeads were first produced from human donors and characterized using histology (safranin O staining of glycosaminoglycan [GAG] and immunohistochemistry of collagen I and II) and GAG dosage. Cartibeads from 6 Göttingen minipigs were engineered and implanted in an autologous condition in the knee (4 or 5 lesions per knee). One group was followed up for 3 months and the other for 6 months. Feasibility and efficacy were measured using histological analysis and macroscopic and microscopic scores.

Cartibeads revealed hyaline features with strong staining of GAG and collagen II. High GAG content was obtained: 24.6-µg/mg tissue (wet weight), 15.52-µg/mg tissue (dry weight), and 35 ± 3-µg GAG/bead (mean ± SD). Histological analysis of Göttingen minipigs showed good integration of Cartibeads grafts at 3 and 6 months after implantation. The Bern Score of the histological assay comparing grafted versus empty lesions was significant at 3 months (grafted, n = 10; nongrafted, n = 4; score, 3.3 and 5.3, respectively) and 6 months (grafted, n = 11; nongrafted, n = 3; score, 1.6 and 5.1).

We developed an innovative 3-step method allowing, for the first time, the use of fully dedifferentiated adult chondrocytes with a high number of cell passage (owing to the extensive amplification in culture). Cartibeads engineered from chondrocytes hold potential as an advanced therapy medicinal product for treating cartilage lesions with established efficacy.

This successful preclinical study, combined with standardized manufacturing of Cartibeads according to good manufacturing practice guidelines, led to the approval of first-in-human clinical trial by the ethics committee and local medical authority. The generated data highlighted a promising therapy to treat cartilage lesions from a small amount of starting biopsy specimen. With our innovative cell amplification technology, very large lesions can be treated, and older active patients can benefit from it.

Although numerous clinical studies have compared transtibial (TT) and anteromedial portal (AMP) drilling of femoral tunnels during anterior cruciate ligament reconstruction (ACLR), there is no high-quality, evidence-based consensus regarding which technique affords the best outcome.

There would be no difference between the TT and AMP techniques in terms of knee stability, patient-reported outcomes, incidence of revision, and radiological results.

Meta-analysis; Level of evidence, 2.

The PubMed and EMBASE databases were searched from inception to February 1, 2021. Level 1 and 2 clinical trials that compared TT and AM techniques were included. Data were meta-analyzed for the outcome measures of knee stability, patient-reported functional outcomes, incidence of revision, and radiological results. Dichotomous variables were presented as odds ratios (ORs), and continuous variables were presented as mean differences (MDs) and standard mean differences (SMDs).

The meta-analysis included 18 clinical studies, level of evidence 1 or 2, that involved 53,888 patients. Pooled data showed that the AMP group had a lower side-to-side difference (SMD, 0.22; 95% CI, 0.06 to 0.39; P = .009), a lower incidence of pivot-shift phenomenon (OR, 3.69; 95% CI, 1.26 to 10.79; P = .02), and a higher postoperative Lysholm score (SMD, −0.26; 95% CI, −0.44 to −0.08; P = .005) than the TT group. However, no statistically significant differences were seen in other outcomes, including subjective International Knee Documentation Committee scores (SMD, –0.11; 95% CI, –0.30 to 0.09; P = .30) or grades (OR, 0.93; 95% CI, 0.35 to 2.49; P = .89), postoperative activity level (MD, –0.14; 95% CI, –0.42 to 0.15; P = .35), and incidence of revision ACLR (OR, 1.04; 95% CI, 0.93 to 1.16; P = .45). The TT technique was more likely to create longer (SMD, 1.05; 95% CI, 0.05 to 2.06; P = .04) and more oblique (SMD, 0.81; 95% CI, 0.51 to 1.11; P < .001) femoral tunnels than the AMP technique, and a higher height ratio of the aperture position was detected with the TT technique (SMD, −3.51; 95% CI, −5.54 to −1.49; P < .001).

The AMP technique for ACLR may be more likely to produce better knee stability and improved clinical outcomes than the TT technique, but no difference was found in the incidence of revision between the 2 groups.

In cases of recurrent anterior shoulder instability with a glenoid defect, Latarjet procedures are widely used for stabilization. Although complications with this procedure have been reported, few studies have comprehensively analyzed issues related to the Latarjet procedure.

To identify the overall complication rate of the Latarjet procedure used for anterior shoulder instability and to compare the rate of complications between arthroscopic and open approaches.

Systematic review; Level of evidence, 4.

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed by using the PubMed, EMBASE, Scopus, and Cochrane Library databases. Data on complications were extracted and classified as intraoperative, postoperative, or instability-related for further analysis. Quality assessments were performed with criteria from the Methodological Index for Nonrandomized Studies (MINORS). A quantitative synthesis of data was conducted to compare the complication rates between arthroscopic and open approaches.

A total of 35 articles were included in this analysis. The MINORS score was 11.89. A total 2560 Latarjet procedures (2532 patients) were included. The overall complication rate was 16.1% (n = 412). The intraoperative complication rate was 3.4% (n = 87) and included a 1.9% (n = 48) incidence of nerve injuries and a 1.0% (n = 25) incidence of iatrogenic fractures. Screw problems, vascular injuries, and conversion arthroscopic to open surgery each occurred at a rate of <1%. The postoperative complication rate was 6.5% (n = 166), and the most common complication was nonunion (1.3%; n = 33). The instability-related complication rate was 6.2% (n = 159) and included a 1.5% (n = 38) rate of redislocation, a 2.9% (n = 75) rate of positive apprehension test, and a 1.0% (n = 26) rate of instability. Overall, 2.6% (n = 66) of patients required an unplanned secondary operation after the initial surgery. The arthroscopic approach was associated with a higher rate of intraoperative complications compared with the open approach (5.0% vs 2.9%; P =.020) and a lower rate of instability-related complications (3.1% vs 7.2%; P < .001).

The Latarjet procedure for anterior shoulder instability results in an overall complication rate of 16.1% and a reoperation rate of 2.6%. However, serious complications at short-term follow-up appear rare. When the arthroscopic approach was used, the rate of intraoperative complications was higher, although instability-related complications were lower when compared with the open approach.

Current recommendations on safe return to sports (RTS) after total hip arthroplasty (THA) are subjective and based on studies of varying quality.

The aim of this study was to synthesize systematic reviews and meta-analyses on post-THA RTS to propose practice guidelines identifying which sports can be resumed, when they can be resumed, and what risks are present.

Systematic review; Level of evidence, 4.

This umbrella review followed the Joanna Briggs Institute (JBI) protocol and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The Embase, Medline, and Cochrane databases were searched. Included studies were either systematic reviews or meta-analyses addressing primary or secondary outcomes. Outcomes of interest included safe sports after THA, time to RTS, prognostic indicators of RTS, reasons patients do not RTS, percentage of patients who RTS, implant complications, and objective classification of sports by impact level. Included reviews had data extracted and were assessed for methodological quality using the JBI protocol. The authors defined RTS as “returning to a sport the patient participated in at any point preoperatively.”

Patients demonstrated a trend toward lower-impact sports postoperatively. Sports were classified as low (eg, walking), moderate (eg, downhill skiing), or high impact (eg, soccer). A total of 82% (range, 55%-104%) of patients were able to RTS at a mean time of 6 months (range, 4-7 months). The best prognostic indicator for RTS was previous experience in that sport. The main reason patients did not RTS was surgeon recommendation. Aseptic loosening was the most cited complication after RTS.

Most patients are able to return to preoperative levels of low- (eg, walking) and moderate-impact (eg, hiking) sports between 7 and 12 months after THA. Patients planning a return to high-impact (eg, singles tennis) sports should be counseled on the possible risks of traumatic injuries and aseptic loosening and monitored closely.

Peripheral nerve blocks (PNBs) are vital in the administration of surgical analgesia and have grown in popularity for use in lower extremity arthroscopic procedures because of their capacity to safely and effectively control pain. The number and specificity of PNBs, however, have made choosing the best option for a procedure nebulous for orthopaedic surgeons.

To present a narrative literature review of the PNBs available for arthroscopic hip and knee procedures that is adapted to an audience of orthopaedic surgeons.

Narrative literature review.

A combination of the names of various lower extremity PNBs AND “hip arthroscopy” OR “knee arthroscopy” was used to search the English medical literature including PubMed, Cochrane Library, ScienceDirect, Embase, and Scopus. Placement technique, specificity of blockade, efficacy, and complications were assessed. Searches were performed through May 2, 2021.

A total of 157 studies were included in this review of lower extremity PNBs. Femoral nerve, lumbar plexus, sciatic nerve, and fascia iliaca compartment blocks were most commonly used in arthroscopic hip surgery, while femoral nerve, 3-in-1, and adductor canal blocks were preferred for arthroscopic knee surgery. Each block demonstrated a significant benefit (P > .05) in ≥1 of the following outcomes: intraoperative morphine, pain scores, nausea, and/or opioid consumption. Combination blocks including the lateral femoral cutaneous nerve block, obturator nerve block, quadratus lumborum block, and L1 and L2 paravertebral block have also been described. Complication rates ranged from 0% to 4.8% in those administered with ultrasound guidance. The most commonly reported complications included muscular weakness, postoperative falls, neuropathy, intravascular and intraneural injections, and hematomas.

When administered properly, PNBs were a safe and effective adjuvant method of pain control with a significant potential to limit postoperative narcotic use. While blockade choice varies by surgeon preference and procedure, all PNBs should be administered with ultrasound guidance, and vigilant protocols for the risk of postoperative falls should be exercised in patients who receive them.