The Predictors of Surgery for Symptomatic, Atraumatic Full-Thickness Rotator Cuff Tears Change Over Time: Ten-Year Outcomes of the MOON Shoulder Prospective Cohort.

BACKGROUND: A prospective cohort study was conducted to assess the predictors of failure of nonoperative treatment, defined as the patient undergoing surgery for symptomatic, atraumatic full-thickness rotator cuff tears. We present the 10-year follow-up data of this population to determine if predictors for surgery change over time, and secondarily we report the outcomes of the cohort. METHODS: At the time of enrollment, demographic, symptom, rotator cuff anatomy, and patient-reported outcome data were collected in patients with symptomatic, atraumatic full-thickness rotator cuff tears. Patients underwent a standard physical therapy protocol for 6 to 12 weeks. Patient data were then collected at 1, 2, 5, 7, and 10 years. Failure of nonoperative treatment was defined as the patient electing to undergo surgery. RESULTS: Of the 452 patients in the original cohort, 20 patients (5%) withdrew from the study, 37 (9%) died before 10 years, and 40 (9%) were otherwise lost to follow-up. A total of 115 patients (27.0%) underwent a surgical procedure at some point during the 10-year follow-up period. Of these patients, 56.5% underwent surgery within 6 months of enrollment and 43.5%, between 6 months and 10 years. Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery. Workers' Compensation status and activity level were more important predictors of later surgery. Patient-reported outcome measures all improved following physical therapy. For patients who did not undergo a surgical procedure, patient-reported outcome measures did not decline over the 10-year follow-up period. CONCLUSIONS: Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery, whereas Workers' Compensation status and activity level were predictors of later surgery. Physical therapy was successful in >70% of patients with symptomatic, atraumatic full-thickness rotator cuff tears at 10 years. Outcome measures improved with physical therapy and did not decline over the 10-year follow-up period. LEVEL OF EVIDENCE: Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Obesity is associated with muscle atrophy in rotator cuff tear.

Objective: The primary goal of this study is to evaluate the relationship between Body Mass Index (BMI) and muscle atrophy in individuals with rotator cuff tears. Methods: This study consists of patients with rotator cuff tears identified by MRI from two independent cohorts, the Rotator Cuff Outcomes Workgroup (ROW) and the Multicenter Orthopaedic Outcomes Network (MOON). Presence of atrophy (yes/no) and severity of atrophy (as an ordinal variable) were assessed on MRI by expert physicians. We used multivariable regression models to evaluate the relationship between BMI and muscle atrophy while adjusting for age and sex in each study, conducted sensitivity analyses for full-thickness tear and combined results using inverse variance-weighted meta-analysis. Results: A total of 539 patients (MOON=395, ROW=144) from the combined cohorts had MRI data available on muscle atrophy. Among these patients, 246 (46%) had atrophy of at least one of the muscles of the rotator cuff and 282 (52%) had full-thickness tears. In meta-analysis across both cohorts, each 5 kg/m2 increase in BMI was associated with a 21% (aOR=1.21, 95% CI=1.02, 1.43) increased odds of having muscle atrophy among individuals with any tear size, and 36% (aOR=1.36, 95% CI=1.01-1.81) increased odds among individuals with full-thickness tear. Conclusions: Higher BMI was associated with significantly higher odds of muscle atrophy in patiens with rotator cuff tears. More study is needed to unders1tand why and how this relationship exists, as well as whether interventions to reduce BMI may help improve outcomes for these patients. Level of Evidence: III.

Meniscus Tears in Elite Athletes: Treatment Considerations, Clinical Outcomes, and Return to Play.

PURPOSE OF REVIEW: Management of meniscal injuries in the elite athlete is a difficult problem secondary to the high demands of athletic competition, the need for a timely return to sport, and the desire to maximize performance over time. The purpose of this review is to provide an up-to-date summary on the current literature and trends regarding the management of meniscus injuries with a special consideration for elite athletes. RECENT FINDINGS: Historically, partial meniscectomy has been the primary treatment option for meniscus injuries. However, in recent years there has been an increased emphasis on meniscus preservation due to the increased risk of cartilage degeneration over time. Moreover, while partial meniscectomy still provides a quicker return to sport (RTS), recent literature has demonstrated similar rates of RTS and return to pre-injury levels between partial meniscectomy and meniscus repair. In the setting of symptomatic meniscal deficiency, meniscus allograft transplantation has become an increasingly utilized salvage procedure with promising yet variable outcomes on the ability to withstand elite competition. Currently, there is no uniform approach to treating meniscal injuries in elite athletes. Therefore, an individualized approach is required with consideration of the meniscus tear type, location, concomitant injuries, athlete expectations, rehabilitation timeline, and desire to prevent or delay knee osteoarthritis. In athletes with anatomically repairable tears, meniscus repair should be performed given the ability to restore native anatomy, provide high rates of RTS, and mitigate long-term chondral damage. However, partial meniscectomy can be indicated for unrepairable tears.

Independent data collectors decrease bias in the measurement of adherence to anterior cruciate ligament injury prevention programs.

OBJECTIVES: Studies on adherence to neuromuscular training (NMT) for anterior cruciate ligament (ACL) injury prevention are frequently biased due to the use of self-reporting by coaches or the athletes themselves. Few NMT studies use data collectors (aside from the athletes or the individuals administering the NMT program) to decrease bias when assessing the adherence of coaches and sports teams. We hypothesized that the use of a data collector who is independent of the team to evaluate adherence to NMT programs would be reliable. METHODS: In a prior a cluster-randomized controlled trial evaluating adherence to NMT training trial, twelve boys' and nine girls' high school athletic teams in a variety of sports were enrolled. Eight data collectors (unaffiliated with the NMT program) were hired specifically to record adherence of the athletes to the NMT exercises at each team's warm-ups 2-3 times a week, prior to practices and games. In addition to the data collectors, a control group of independent observers made visits throughout the season to also record adherence (solely for the purpose of this study, alongside the data collectors and in the same fashion) in order to evaluate the data collectors' performance and determine inter-observer reliability. The inter-observer reliability between data collectors and independent observers was measured using the Kappa statistic. RESULTS: A total of 399 warm-ups for practices or games were observed by data collectors to obtain adherence data. Independent observers also measured adherence at 58 practices or games for inter-observer reliability. Exercise instruction and alignment cues for 29 different exercises were analysed. The Kappa values ranged from 0.63 to 1.0, indicating substantial to perfect agreement. The overall Kappa values of 0.89 and 0.90 for exercise instruction and alignment cues, respectively, indicated almost perfect agreement. CONCLUSION: The use of a data collector who is independent of the team to evaluate adherence to NMT programs (rather than athlete or coach self-reporting), was shown to be a reliable method for measurement of adherence in studies of NMT for injury prevention. Avoiding self-reporting in adherence research to NMT training may decrease bias. LEVEL OF EVIDENCE: I.

Factors Associated With Humeral Avulsion of Glenohumeral Ligament Lesions in Patients With Anterior Shoulder Instability: An Analysis of the MOON Shoulder Instability Cohort.

Background: Humeral avulsion of the glenohumeral ligament (HAGL) lesions are an uncommon cause of anterior glenohumeral instability and may occur in isolation or combination with other pathologies. As HAGL lesions are difficult to detect via magnetic resonance imaging (MRI) and arthroscopy, they can remain unrecognized and result in continued glenohumeral instability. Purpose: To compare patients with anterior shoulder instability from a large multicenter cohort with and without a diagnosis of a HAGL lesion and identify preoperative physical examination findings, patient-reported outcomes, imaging findings, and surgical management trends associated with HAGL lesions. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients with anterior glenohumeral instability who underwent surgical management between 2012 and 2020 at 11 orthopaedic centers were enrolled. Patients with HAGL lesions identified intraoperatively were compared with patients without HAGL lesions. Preoperative characteristics, physical examinations, imaging findings, intraoperative findings, and surgical procedures were collected. The Student t test, Kruskal-Wallis H test, Fisher exact test, and chi-square test were used to compare groups. Results: A total of 21 HAGL lesions were identified in 915 (2.3%) patients; approximately one-third (28.6%) of all lesions were visualized intraoperatively but not identified on preoperative MRI. Baseline characteristics did not differ between study cohorts. Compared with non-HAGL patients, HAGL patients were less likely to have a Hill-Sachs lesion (54.7% vs 28.6%; P = .03) or an anterior labral tear (87.2% vs 66.7%; P = .01) on preoperative MRI and demonstrated increased external rotation when their affected arm was positioned at 90° of abduction (85° vs 90°; P = .03). Additionally, HAGL lesions were independently associated with an increased risk of undergoing an open stabilization surgery (odds ratio, 74.6 [95% CI, 25.2-221.1]; P < .001). Conclusion: Approximately one-third of HAGL lesions were missed on preoperative MRI. HAGL patients were less likely to exhibit preoperative imaging findings associated with anterior shoulder instability, such as Hill-Sachs lesions or anterior labral pathology. These patients underwent open procedures more frequently than patients without HAGL lesions.

Predictors of Return to Activity at 2 Years After Anterior Cruciate Ligament Reconstruction Among Patients With High Preinjury Marx Activity Scores: A MOON Prospective Cohort Study.

BACKGROUND: Predictors of return to activity after anterior cruciate ligament reconstruction (ACLR) among patients with relatively high preinjury activity levels remain poorly understood. PURPOSE/HYPOTHESIS: The purpose of this study was to identify predictors of return to preinjury levels of activity after ACLR, defined as achieving a Marx activity score within 2 points of the preinjury value, among patients with Marx activity scores of 12 to 16 who had been prospectively enrolled in the Multicenter Orthopaedic Outcomes Network (MOON) cohort. We hypothesized that age, sex, preinjury activity level, meniscal injuries and/or procedures, and concurrent articular cartilage injuries would predict return to preinjury activity levels at 2 years after ACLR. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: All unilateral ACLR procedures from 2002 to 2008 performed in patients enrolled in the MOON, with preinjury Marx activity scores ranging from 12 to 16, were evaluated with a specific focus on return to preinjury activity levels at 2 years postoperatively. Return to activity was defined as a Marx activity score within 2 points of the preinjury value. The proportion of patients able to return to preinjury activity levels was calculated, and multivariable modeling was performed to identify risk factors for patients' inability to return to preinjury activity levels. RESULTS: A total of 1188 patients were included in the final analysis. The median preinjury Marx activity score was 16 (interquartile range, 12-16). Overall, 466 patients (39.2%) were able to return to preinjury levels of activity, and 722 patients (60.8%) were not able to return to preinjury levels of activity. Female sex, smoking at the time of ACLR, fewer years of education, lower 36-Item Short Form Health Survey Mental Component Summary scores, and higher preinjury Marx activity scores were predictive of patients' inability to return to preinjury activity levels. Graft type, revision ACLR, the presence of medial and/or lateral meniscal injuries, a history of meniscal surgery, the presence of articular cartilage injuries, a history of articular cartilage treatment, and the presence of high-grade knee laxity were not predictive of a patient's ability to return to preinjury activity level. CONCLUSION: At 2 years after ACLR, most patients with high preinjury Marx activity scores did not return to their preinjury level of activity. The higher the preinjury Marx activity score that a patient reported at the time of enrollment, the less likely he/she was able to return to preinjury activity level. Smoking and lower mental health at the time of ACLR were the only modifiable risk factors in this cohort that predicted an inability to return to preinjury activity levels. Continued effort and investigation are required to maximize functional recovery after ACLR in patients with high preinjury levels of activity.

Development and Validation of a Short-Form Version of the Western Ontario Shoulder Instability Scale (Short-WOSI).

BACKGROUND: Patient-reported outcome measures (PROMs) have transitioned from primarily being used as research instruments to becoming increasingly used in the clinical setting to assess recovery and inform shared decision-making. However, there is a need to develop validated short-form PROM instruments to decrease patient burden and ease incorporation into clinical practice. PURPOSE: To assess the validity and responsiveness of a shortened version of the Western Ontario Shoulder Instability Index (Short-WOSI) when compared with the full WOSI and other shoulder-related PROM instruments. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: This study was a secondary analysis of data collected as part of an institutional review board-approved, multicenter cohort of 1160 patients undergoing surgical stabilization for shoulder instability. The following PROMs were captured preoperatively and 2 years after surgery: WOSI, American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), and 36-Item Health Survey (RAND-36). The cohort was split into 2 data sets: a training set to be used in the development of the Short-WOSI (n = 580) and a test set to be used to assess the validity and responsiveness of the Short-WOSI relative to the full WOSI, ASES, SANE, and RAND-36. RESULTS: The Short-WOSI demonstrated excellent internal consistency before surgery (Cronbach α = .83) and excellent internal consistency at the 2-year follow-up (Cronbach α = .93). The baseline, 2-year, and pre- to postoperative changes in Short-WOSI and WOSI were closely correlated (r > 0.90), with both demonstrating large effect sizes (Short-WOSI = 1.92, WOSI = 1.81). Neither the Short-WOSI nor the WOSI correlated well with the other PROM instruments before (r = 0.21-0.33) or after (r = 0.25-0.38) surgery. The Short-WOSI, WOSI, and SANE scores were more responsive than ASES and RAND-36 scores. CONCLUSION: The 7-item Short-WOSI demonstrated excellent internal consistency and a lack of floor or ceiling effects. The Short-WOSI demonstrated excellent cross-sectional and longitudinal construct validity and was similarly responsive over time as the full WOSI. Neither the Short-WOSI nor WOSI correlated with more general shoulder PROMs, underscoring the advantage of using instability-specific instruments for this population.

Radiographic Changes Five Years After Treatment of Meniscal Tear and Osteoarthritic Changes.

OBJECTIVE: Meniscal tear in persons aged ≥45 years is typically managed with physical therapy (PT), and arthroscopic partial meniscectomy (APM) is offered to those who do not respond. Prior studies suggest APM may be associated with greater progression of radiographic changes. METHODS: We assessed changes between baseline and 60 months in the Kellgren-Lawrence (KL) grade and OARSI radiographic score (including subscores for joint space narrowing and osteophytes) in subjects aged 45-85 years enrolled into a seven-center randomized trial comparing outcomes of APM with PT for meniscal tear, osteoarthritis changes, and knee pain. The primary analysis classified subjects according to treatment received. To balance APM and PT groups, we developed a propensity score and used inverse probability weighting (IPW). We imputed a 60-month change in the OARSI score for subjects who underwent total knee replacement (TKR). In a sensitivity analysis, we classified subjects by randomization group. RESULTS: We analyzed data from 142 subjects (100 APM, 42 PT). The mean ± SD weighted baseline OARSI radiographic score was 3.8 ± 3.5 in the APM group and 4.0 ± 4.9 in the PT group. OARSI scores increased by a mean of 4.1 (95% confidence interval [95% CI] 3.5-4.7) in the APM group and 2.4 (95% CI 1.7-3.2) in the PT group (P < 0.001) due to changes in the osteophyte component. We did not observe statistically significant differences in the KL grade. Sensitivity analyses yielded similar findings to the primary analysis. CONCLUSION: Subjects treated with APM had greater progression in the OARSI score because of osteophyte progression but not in the KL grade. The clinical implications of these findings require investigation.

Higher Adherence to Anterior Cruciate Ligament Injury Prevention Programs Is Associated With Lower Injury Rates: A Meta-Analysis and Meta-Regression.

Background: Athletes who participate in sports that involve cutting and pivoting movements are particularly susceptible to anterior cruciate ligament (ACL) injury. Preventing this injury is the best way to combat its health consequences and costs. There may be a dose-response relationship between adherence and injury reduction. Purpose: We sought to examine whether athletes' adherence to injury prevention programs (IPPs) is associated with reductions in ACL and lower extremity (LE) injuries. Methods: We conducted a systematic review of the PubMed, EMBASE, and Cochrane Library databases, searching for studies published between 2011 and 2021. Studies were included if they reported on the use of an ACL IPP compared with a control group and recorded the rate of injuries to calculate a rate ratio, as well as adherence to the program as a percentage of sessions performed. For the meta-analysis, the rate ratios were pooled using the DerSimonian-Laird random-effects model. Results: For the 15 studies included (11 randomized controlled trials and 4 cohort studies), the random-effects model grouped athletes' adherence to an IPP as high (76% or more of the sessions), moderate (51%-75% of the sessions), and low (50% or fewer of the sessions). We found that athletes with the highest level of IPP adherence had a significantly lower incidence of ACL injury. The rate ratios for moderate and low adherence did not demonstrate a reduced incidence of ACL injury. Injury prevention program participation was also associated with a decrease in LE injury rates. Conclusion: This systematic review and meta-analysis found that athletes with high adherence to IPPs had reduced rates of ACL and LE injuries. Our findings suggest that educating coaches and athletes on the dose-dependent benefits of IPPs may promote the routine incorporation of these programs into warm-up sessions to decrease the risk of ACL and LE injuries.

Predictors of Bone Loss in Anterior Glenohumeral Instability.

BACKGROUND: Anterior shoulder instability can result in bone loss of both the anterior glenoid and the posterior humerus. Bone loss has been shown to lead to increased failure postoperatively and may necessitate more complex surgical procedures, resulting in worse clinical outcomes and posttraumatic arthritis. HYPOTHESIS/PURPOSE: The purpose of this study was to investigate predictors of glenoid and humeral head bone loss in patients undergoing surgery for anterior shoulder instability. It was hypothesized that male sex, contact sport participation, traumatic dislocation, and higher number of instability events would be associated with greater bone loss. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 892 patients with anterior shoulder instability were prospectively enrolled in the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort. The presence and amount of anterior glenoid bone loss and accompanying Hill-Sachs lesions were quantified. Descriptive information and injury history were used to construct proportional odds models for the presence of any bone defect, for defects >10% of the anterior glenoid or humeral head, and for combined bony defects. RESULTS: Anterior glenoid bone loss and Hill-Sachs lesions were present in 185 (20.7%) and 470 (52.7%) patients, respectively. Having an increased number of dislocations was associated with bone loss in all models. Increasing age, male sex, and non-White race were associated with anterior glenoid bone defects and Hill-Sachs lesions. Contact sport participation was associated with anterior glenoid bone loss, and Shoulder Actitvity Scale with glenoid bone loss >10%. A positive apprehension test was associated with Hill-Sachs lesions. Combined lesions were present in 19.4% of patients, and for every additional shoulder dislocation, the odds of having a combined lesion was 95% higher. CONCLUSION: An increasing number of preoperative shoulder dislocations is the factor most strongly associated with glenoid bone loss, Hill-Sachs lesions, and combined lesions. Early surgical stabilization before recurrence of instability may be the most effective method for preventing progression to clinically significant bone loss. Patients should be made aware of the expected course of shoulder instability, especially in athletes at high risk for recurrence and osseous defects, which may complicate care and worsen outcomes. REGISTRATION: NCT02075775 (ClinicalTrials.gov identifier).

Graft choices for paediatric anterior cruciate ligament reconstruction: State of the art.

The paediatric population is at particularly high risk for anterior cruciate ligament (ACL) injuries due to high rates of sports participation. Other risk factors for ACL injuries in children include but are not limited to being female, generalised ligamentous laxity, a high body mass index (BMI), and poor neuromuscular control. ACL reconstruction (ACLR) is commonly done to treat ACL injuries and allow for return to sports and daily activities. ACL repair is another option with ongoing techniques being developed. The high rates of graft failure in children reported in recent publications on ACL repair are very concerning. Special consideration must be taken in ACLR in the skeletally immature patient due to the risk of growth-related complications, such as limb deformity or growth arrest, that can arise from drilling across or disrupting the physis. Graft choices for paediatric ACLR include iliotibial band (ITB) over the top and over the front, hamstring autograft, bone patellar tendon bone (BTB) autograft, quadriceps tendon autograft, and allograft. Factors for each graft choice to consider include graft size, graft failure rates, donor site morbidity, requirement for bony tunnels, the post-op rehabilitation process, and return to sport outcomes. Each graft has its benefits and disadvantages for the individual patient, depending on age, skeletal maturity, and goals for recovery. Lateral extra-articular tenodesis (LET) is another option to consider with paediatric ACLR because LET has been shown to decrease the re-rupture rate in adult ACLR. After surgery, patient follow-up until at least the growth plates are closed is important. This article aims to provide an overview and comparison of the various graft types to aid in the graft choice decision making process for paediatric ACLR.

Association Between Structural Change Over Eighteen Months and Subsequent Symptom Change in Middle-Aged Patients Treated for Meniscal Tear.

OBJECTIVE: Middle-aged subjects with meniscal tear treated with arthroscopic partial meniscectomy (APM) experience greater progression of damage to joint structures on imaging than subjects treated nonoperatively. It is unclear whether these changes are clinically relevant. The goal of this study was to assess whether worsening in magnetic resonance imaging (MRI)-assessed tissue damage over 18 months leads to subsequent worsening in knee pain over the subsequent 3.5 years. METHODS: We used data from the Meniscal Tear in Osteoarthritis Research (MeTeOR) trial of APM versus physical therapy for subjects ages ≥45 years with knee pain, cartilage damage, and meniscal tear. We assessed whether change in cartilage surface area damage score (and other structural measures) from baseline to 18 months, assessed on MRI with the MRI Osteoarthritis Knee Score (MOAKS) system, was associated with change in Knee Injury and Osteoarthritis Outcome Score (KOOS) pain score (range 0-100; 100 = worst) from 18 to 60 months. RESULTS: The primary analysis included 168 subjects with complete MRI data at baseline and 18 months and KOOS data at 18 and 60 months. We did not observe clinically important associations between change in cartilage surface area score between baseline and 18 months and change in pain scores from 18 to 60 months. Pain scores in the worst tertile for cartilage surface area damage score progression worsened by 0.45 points more than in the best tertile (95% confidence interval -4.45, 5.35). Similarly, we did not observe clinically important associations between changes in bone marrow lesions, osteophytes, or synovitis and subsequent pain. CONCLUSION: We did not observe clinically important associations between early changes in cartilage damage and other structural measures and worsening in pain over the subsequent 3.5 years. Further follow-up is required to assess this association over a longer follow-up period.

A Controlled Trial of the Effects of Neuromuscular Training on Physical Performance in Male and Female High School Athletes.

BACKGROUND: Neuromuscular training (NMT) has demonstrated efficacy as an intervention to decrease the risk of anterior cruciate ligament injuries and improve sports performance. The effect of this training on the mechanisms that contribute to improved physical performance has not been well defined. HYPOTHESIS: Athletes in the NMT group will have better mechanisms of fundamental movements and agility tests that may contribute to improved sports performance. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 2. METHODS: Eight high school teams (111 athletes, 53% male, mean age 16 years) participated, with half performing NMT. Physical performance was measured using the dorsaVi ViPerform system, a US Food and Drug Administration-cleared wireless sensor system. Agility was assessed using a timed 3-cone test. Independent sample t tests were used to compare differences between the intervention and control groups. RESULTS: Matched pre- and postseason data were collected from 74 athletes after excluding athletes with injury and those lost to follow-up. Significant improvements were observed in the NMT group for loading/landing speed ratios during a single-leg hop test (right lower extremity = -0.19 [-0.37, 0.03], P = 0.03 and left lower extremity = -0.27 [-0.50, -0.03], P = 0.03). The control group had lower ground reaction forces compared with the NMT group (P < 0.02), while significant improvements were found in the NMT group for initial peak acceleration (P < 0.02) and cadence (P = 0.01) during a straight-line acceleration/deceleration test. For the 3-cone agility test, the postseason time decreased compared with preseason in the NMT group, whereas the time for the control group increased (-0.37 s vs 0.14 s, P < 0.00). CONCLUSION: The results demonstrate that NMT administered by sports medicine clinicians can significantly improve some physical performance of fundamental movements in high school athletes. CLINICAL RELEVANCE: Coaches should be trained to effectively deliver NMT in order to improve sports performance.

Return to Play after Posterior Cruciate Ligament Injuries.

PURPOSE OF REVIEW: Posterior cruciate ligament injuries can be treated conservatively with a structured rehabilitation program or with surgical reconstruction. Treatment algorithms are based on a variety of factors including the patient's presentation, physical exam, and desired level of activity. The goal is to return the patient to their athletic pursuits with a stable and pain-free knee. Return to play and activities should be individualized based on the patient's injury and progression through rehabilitation. This article provides a review of the current treatments for posterior cruciate ligament injuries and the respective rehabilitation protocols, outcomes after each treatment option, and specific return to play criteria. RECENT FINDINGS: Current research shows excellent outcomes and return to play with conservative treatment of isolated posterior cruciate ligament injuries. Return to play algorithms stress the importance of quadriceps strengthening throughout the recovery process and emphasize inclusion of plyometrics and sport-specific training. Rehabilitation plays a critical role in the outcome after posterior cruciate ligament injury and the ability to return to athletics. The primary focus of post-injury or post-operative rehabilitation is to restore function, as it relates to range of motion, strength, and proprioception, while mitigating swelling and pain. The patients' desired sport and level of play dictate return to play timelines. The literature supports the use of non-operative management of isolated PCL injuries in athletes and non-athletes with excellent functional and patient-reported outcomes.

Factors Associated With Shoulder Activity Level at Time of Surgery and at 2-Year Follow-up in Patients Undergoing Shoulder Stabilization Surgery.

BACKGROUND: Patients undergoing shoulder stabilization surgery have been shown to have elevated activity levels. Factors associated with shoulder activity in this patient population at baseline and after surgery are unknown. HYPOTHESIS: Patient-specific variables are associated with shoulder activity level at baseline and at 2-year follow-up in a cohort of patients undergoing shoulder stabilization surgery. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients undergoing shoulder stabilization surgery were prospectively enrolled. As part of the data collection process, patients completed a previously validated Shoulder Activity Scale. A regression analysis was performed to assess the association of patient characteristics with baseline and 2-year follow-up shoulder activity levels. RESULTS: A total of 764 (n = 612 men, n = 152 women) out of 957 patients (80%) undergoing shoulder stabilization surgery with a median age of 25 years had baseline and 2-year follow-up data and were included in the current analysis. The baseline shoulder activity level was associated with race ( P < .0001) and preoperative duration of instability (P < .0001). At 2 years, 52% of the cohort had returned to the same or higher activity level after surgery. Predictors of higher shoulder activity level at 2-year follow-up included higher baseline activity level (P < .0001), male sex (P < .0001), younger age (P = .004), higher body mass index (BMI) (P = .03), more dislocations (P = .03), nonsmokers (P = .04), and race (P = .04). CONCLUSION: A longer duration of preoperative symptoms was associated with a lower baseline activity in this cohort. High baseline preoperative shoulder activity, younger age, male sex, higher BMI, number of dislocations, and nonsmoking status predicted higher shoulder activity 2 years after shoulder stabilization surgery. REGISTRATION: NCT02075775 (ClinicalTrials.gov identifier).

Five-Year Structural Changes in the Knee Among Patients With Meniscal Tear and Osteoarthritis: Data From a Randomized Controlled Trial of Arthroscopic Partial Meniscectomy Versus Physical Therapy.

OBJECTIVE: To estimate the risk of magnetic resonance imaging (MRI)-based structural changes in knee osteoarthritis (OA) among individuals with meniscal tear and knee OA, using MRIs obtained at baseline and 18 and 60 months after randomization in a randomized controlled trial of arthroscopic partial meniscectomy (APM) versus physical therapy (PT). METHODS: We used data from the Meniscal Tear in Osteoarthritis Research (METEOR) trial. MRIs were read using the MRI OA Knee Score (MOAKS). We used linear mixed-effects models to examine the association between treatment group and continuous MOAKS summary scores, and Poisson regression to assess categorical changes in knee joint structure. Analyses assessed changes in OA between baseline and month 18 and between months 18 and 60. We performed both intention-to-treat and as-treated analyses. RESULTS: The analytic sample included 302 participants. For both treatment groups, more OA changes were seen during the early interval than during the later interval. ITT analysis revealed that, between baseline and month 18, APM was significantly associated with an increased risk of having a worsening cartilage surface area score, involving both any worsening across all knee joint subregions (risk ratio [RR] 1.35 [95% confidence interval (95% CI) 1.14, 1.61]) and the number of subregions damaged (RR 1.44 [95% CI 1.13, 1.85]) having a worsening effusion-synovitis score (RR 2.62 [95% CI 1.32, 5.21]), and having ≥1 additional subregion with osteophytes (RR 1.24 [95% CI 1.02, 1.50]). Significant associations were detected between months 18 and 60 only for having any subregion with a worsening osteophyte score (RR 1.28 [95% CI 1.04, 1.58]). CONCLUSION: These findings suggest that the association between APM and MRI-based structural changes in knee OA is most apparent during the initial 18 months after surgery. The reason for attenuation of this association over longer follow-up merits further investigation.

Factors Associated With an Intra-articular Infection After Anterior Cruciate Ligament Reconstruction: A Large Single-Institution Cohort Study.

BACKGROUND: An intra-articular infection after anterior cruciate ligament (ACL) reconstruction (ACLR) is a rare complication but one with potentially devastating consequences. The rare nature of this complication raises difficulties in detecting risk factors associated with it and with worse outcomes after one has occurred. PURPOSE: To (1) evaluate the association between an infection after ACLR and potential risk factors in a large single-center cohort of patients who had undergone ACLR and (2) assess the factors associated with ACL graft retention versus removal. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: All ACLR procedures performed at our institution between January 2010 and December 2018 were reviewed; a total of 11,451 procedures were identified. A retrospective medical record review was performed to determine the incidence of infections, patient and procedure characteristics associated with an infection, infection characteristics, incidence of ACL graft retention, and factors associated with the retention versus removal of an ACL graft. Multivariable logistic regression analysis was used to identify potential risk factors for an infection after ACLR. RESULTS: Of the 11,451 ACLR procedures, 48 infections were identified (0.42%). Multivariable logistic regression analysis revealed revision ACLR (odds ratio [OR], 3.13 [95% CI, 1.55-6.32]; P = .001) and younger age (OR, 1.06 [95% CI, 1.02-1.10]; P = .001) as risk factors for an infection. Compared with bone-patellar tendon-bone autografts, both hamstring tendon autografts (OR, 4.39 [95% CI, 2.15-8.96]; P < .001) and allografts (OR, 5.27 [95% CI, 1.81-15.35]; P = .002) were independently associated with an increased risk of infections. Overall, 15 ACL grafts were removed (31.3%). No statistically significant differences besides the number of irrigation and debridement procedures were found for retained versus removed grafts, although some trends were identified (P = .054). CONCLUSION: In a large single-center cohort of patients who had undergone ACLR and those with an infection after ACLR, patients with revision cases and younger patients were found to have a higher incidence of infection. The use of bone-patellar tendon-bone autografts was found to be associated with the lowest risk of infection after ACLR compared with both hamstring tendon autografts and allografts. Larger cohorts with a larger number of infection cases are needed to determine the factors associated with graft retention versus removal.

Obesity and sex influence fatty infiltration of the rotator cuff: the Rotator Cuff Outcomes Workgroup (ROW) and Multicenter Orthopaedic Outcomes Network (MOON) cohorts.

BACKGROUND: Fatty infiltration (FI) is one of the most important prognostic factors for outcomes after rotator cuff surgery. Established risk factors include advancing age, larger tear size, and increased tear chronicity. A growing body of evidence suggests that sex and obesity are associated with FI; however, data are limited. METHODS: We recruited 2 well-characterized multicenter cohorts of patients with rotator cuff tears (Multicenter Orthopaedic Outcomes Network [MOON] cohort [n = 80] and Rotator Cuff Outcomes Workgroup [ROW] cohort [n = 158]). We used multivariable logistic regression to evaluate the relationship between body mass index (BMI) and the presence of FI while adjusting for the participant's age at magnetic resonance imaging, sex, and duration of shoulder symptoms, as well as the cross-sectional area of the tear. We analyzed the 2 cohorts separately and performed a meta-analysis to combine estimates. RESULTS: A total of 27 patients (33.8%) in the Multicenter Orthopaedic Outcomes Network (MOON) cohort and 57 patients (36.1%) in the Rotator Cuff Outcomes Workgroup (ROW) cohort had FI. When BMI < 25 kg/m2 was used as the reference category, being overweight was associated with a 2.37-fold (95% confidence interval [CI], 0.77-7.29) increased odds of FI and being obese was associated with a 3.28-fold (95% CI, 1.16-9.25) increased odds of FI. Women were 4.9 times (95% CI, 2.06-11.69) as likely to have FI as men. CONCLUSIONS: Among patients with rotator cuff tears, obese patients had a substantially higher likelihood of FI. Further research is needed to assess whether modifying BMI can alter FI in patients with rotator cuff tears. This may have significant clinical implications for presurgical surgical management of rotator cuff tears. Sex was also significantly associated with FI, with women having higher odds of FI than men. Higher odds of FI in female patients may also explain previously reported early suboptimal outcomes of rotator cuff surgery and higher pain levels in female patients as compared with male patients.

Chronic Popliteus Tendon Avulsion Fracture with Chronic Knee Pain and Locking: A Case Report.

CASE: A 31-year-old man who had a chronic popliteus avulsion fracture 18 years earlier treated with physical therapy presented with new onset left knee locking after exercising at the gym. Magnetic resonance imaging demonstrated a chronic popliteus avulsion fracture of the lateral femoral condyle. Surgical excision of the nonunited bone fragment was performed. CONCLUSION: Isolated popliteus avulsion fractures are extremely rare injuries that occur primarily in a skeletally immature patient population and for which treatment options are not well understood. Treatment options include conservative management and early surgical intervention, both of which have inherent risks and benefits. We recommend prompt imaging with computed tomography (CT) to better characterize the degree of injury and follow-up CT imaging in patients who do not undergo early surgical intervention.