MRI-derived Articular Cartilage Strains Predict Patient-Reported Outcomes Six Months Post Anterior Cruciate Ligament Reconstruction.

Key terms: Multicontrast and Multiparametric, Magnetic Resonance Imaging, Osteoarthritis, Functional Biomechanical Imaging, Knee Joint Degeneration What is known about the subject: dualMRI has been used to quantify strains in a healthy human population in vivo and in cartilage explant models. Previously, OA severity, as determined by histology, has been positively correlated to increased shear and transverse strains in cartilage explants. What this study adds to existing knowledge: This is the first in vivo use of dualMRI in a participant demographic post-ACL reconstruction and at risk for developing osteoarthritis. This study shows that dualMRI-derived strains are more significantly correlated with patient-reported outcomes than any MRI relaxometry metric. Background: Anterior cruciate ligament (ACL) injuries lead to an increased risk of osteoarthritis, characterized by altered cartilage tissue structure and function. Displacements under applied loading by magnetic resonance imaging (dualMRI) is a novel MRI technique that can be used to quantify mechanical strain in cartilage while undergoing a physiological load. Purpose: To determine if strains derived by dualMRI and relaxometry measures correlate with patient-reported outcomes at six months post unilateral ACL reconstruction. Study Design: Cohort study. Methods: Quantitative MRI (T2, T2*, T1ρ) measurements and transverse, axial, and shear strains were quantified in the medial articular tibiofemoral cartilage of 35 participants at six-months post unilateral ACL reconstruction. The relationships between patient-reported outcomes (WOMAC, KOOS, MARS) and all qMRI relaxation times were quantified using general linear mixed-effects models. A combined best-fit multicontrast MRI model was then developed using backwards regression to determine the patient features and MRI metrics that are most predictive of patient-reported outcome scores. Results: Higher femoral strains were significantly correlated with worse patient-reported functional outcomes. Femoral shear and transverse strains were positively correlated with six-month KOOS and WOMAC scores, after controlling for covariates. No relaxometry measures were correlated with patient-reported outcome scores. We identified the best-fit model for predicting WOMAC score using multiple MRI measures and patient-specific information, including sex, age, graft type, femoral transverse strain, femoral axial strain, and femoral shear strain. The best-fit model significantly predicted WOMAC score (p<0.001) better than any one individual MRI metric alone. When we regressed the model-predicted WOMAC scores against the patient-reported WOMAC scores, we found that our model achieved a goodness of fit exceeding 0.52. Conclusions: This work presents the first use of dualMRI in vivo in a cohort of participants at risk for developing osteoarthritis. Our results indicate that both shear and transverse strains are highly correlated with patient-reported outcome severity could serve as novel imaging biomarkers to predict the development of osteoarthritis.

Most Orthopaedic Platelet-Rich Plasma Investigations Don't Report Protocols and Composition: An Updated Systematic Review.

PURPOSE: To systematically review the literature to assess the heterogeneity of platelet-rich plasma (PRP) preparation and composition reporting for the treatment of musculoskeletal/orthopaedic pathologies. METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I and Level II studies from 2016 to 2022 that evaluated the use of PRP therapy for musculoskeletal pathologies. The search phrase used was "platelet-rich plasma clinical studies." Studies were assessed based on their reporting of the PRP preparation methods and reporting of PRP composition. RESULTS: One hundred twenty-four studies (in 120 articles) met inclusion criteria for analysis. Of these studies, 15 (12.1%) provided comprehensive reporting, including a clear, well-described, and reproducible preparation protocol that future investigators can follow. Thirty-three studies (26.6%) quantitatively reported the final PRP product composition. CONCLUSIONS: Among the studies using PRP for the treatment of musculoskeletal/orthopaedic pathologies, less than 20% provided a clear, well-described, and reproducible PRP preparation protocol, and only one-fourth of studies reported on the final PRP product composition. CLINICAL RELEVANCE: A diverse current reporting of PRP composition between studies provides a high heterogeneity of the term "PRP," which becomes a limitation for a comparison of studies using PRP.

Patient Perception of Social Media Use by Orthopaedic Surgeons: A Pilot Study.

Background: Social media (SM) use by orthopaedic surgeons is becoming increasingly common; nonetheless, it needs to be clarified how patients perceive the content posted by physicians. Purpose: To characterize SM content posted by orthopaedic surgeons while investigating patient perceptions of this content and how it may influence their health care decisions. Study Design: Cross-sectional study. Methods: Posts on SM outlets by orthopaedic surgeons were reviewed and categorized. A survey to assess patient perception of these categories was administered between December 2021 and February 2022 in the clinics of 3 orthopaedic surgeons. Survey results were analyzed for differences in patient SM use and perception of SM content types. Results: There were 250 completed surveys. SM use was high among all age groups; however, the 18 to 24 years (87.1%) and 25 to 34 years (86.4%) age groups were more likely than older age groups to report daily use (P = .002). Overall, 17% of patients reported using SM to see information about their health care at least once per month, 21% reported reviewing the SM account of a physician at least once per month, 19% reported that they were likely or very likely to view the SM account of their physician, and 23% reported that SM content was likely or very likely to influence which physician they see. Patients held the most consistently positive view of posts that educated patients, discussed sports team coverage, and provided patient testimonials. Patients had consistently neutral views of posts educating colleagues, discussing presentations at national meetings, displaying aspects of surgeons' personal lives, and supporting marginalized groups. Several post categories elicited highly polarized responses-including those discussing research publications and showing surgical techniques or pictures/videos taken during surgery. Respondents had a consistently negative response to posts making political statements. Conclusion: SM is likely a useful tool to help physicians interact with patients. Physicians who wish to interact with patients should consider posting content viewed most positively-including posts educating patients, discussing sports team coverage, and providing patient testimonials. Content that is viewed less favorably should be posted sparingly or with a sensitive tag.

Autograft Demonstrates Superior Outcomes for Revision Anterior Cruciate Ligament Reconstruction When Compared With Allograft: A Systematic Review.

BACKGROUND: Multiple studies have compared outcomes among patients undergoing revision anterior cruciate ligament reconstruction (ACLR) with autograft versus allograft, but these data are inconsistently reported and long-term outcomes depending on graft type are yet to be determined. PURPOSE: To perform a systematic review of clinical outcomes after revision ACLR (rACLR) with autograft versus allograft. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic review of the literature was performed by searching PubMed, the Cochrane Library, and Embase to identify studies that compared the outcomes of patients undergoing rACLR with autograft versus allograft. The search phrase used was autograft allograft revision anterior cruciate ligament reconstruction. Graft rerupture rates, return-to-sports rates, anteroposterior laxity, and patient-reported outcome scores (subjective International Knee Documentation Committee, Tegner, Lysholm, and Knee injury and Osteoarthritis Outcome Score) were evaluated. RESULTS: Eleven studies met inclusion criteria, including 3011 patients undergoing rACLR with autograft (mean age, 28.9 years) and 1238 patients undergoing rACLR with allograft (mean age, 28.0 years). Mean follow-up was 57.3 months. The most common autograft and allograft types were bone-patellar tendon-bone grafts. Overall, 6.2% of patients undergoing rACLR experienced graft retear, including 4.7% in the autograft group and 10.2% in the allograft group (P < .0001). Among studies that reported return-to-sports rates, 66.2% of patients with an autograft returned to sports as opposed to 45.3% of patients with an allograft (P = .01). Two studies found significantly greater postoperative knee laxity in the allograft group as compared with the autograft group (P < .05). Among all patient-reported outcomes, 1 study found 1 significant difference between groups: patients with an autograft had a significantly higher postoperative Lysholm score when compared with patients with an allograft. CONCLUSION: Patients undergoing revision ACLR with an autograft can be expected to experience lower rates of graft retear, higher rates of return to sports, and less postoperative anteroposterior knee laxity when compared with patients undergoing revision ACLR with an allograft.

Immobilization in External Rotation Versus Arthroscopic Stabilization After Primary Anterior Shoulder Dislocation: A Systematic Review of Level 1 and 2 Studies.

BACKGROUND: Arthroscopic stabilization has been established as a superior treatment option for primary glenohumeral instability when compared with immobilization in internal rotation. However, immobilization in external rotation (ER) has recently gained interest as a viable nonoperative treatment option for patients with shoulder instability. PURPOSE: To compare the rates of recurrent instability and subsequent surgery in patients undergoing treatment for primary anterior shoulder dislocation with arthroscopic stabilization versus immobilization in ER. STUDY DESIGN: Systematic review; Level of evidence, 2. METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify studies that'evaluated patients being treated for primary anterior glenohumeral dislocation with either arthroscopic stabilization or immobilization in ER. The search phrase used various combinations of the keywords/phrases "primary closed reduction,""anterior shoulder dislocation,""traumatic,""primary,""treatment,""management,""immobilization,""external rotation,""surgical,""operative,""nonoperative," and "conservative." Inclusion criteria included patients undergoing treatment for primary anterior glenohumeral joint dislocation with either immobilization in ER or arthroscopic stabilization. Rates of recurrent instability, subsequent stabilization surgery, return to sports, positive postintervention apprehension tests, and patient-reported outcomes were evaluated. RESULTS: The 30 studies that met inclusion criteria included 760 patients undergoing arthroscopic stabilization (mean age, 23.1 years; mean follow-up time, 55.1 months) and 409 patients undergoing immobilization in ER (mean age, 29.8 years; mean follow-up time, 28.8 months). Overall, 8.8% of operative patients experienced recurrent instability at latest follow-up compared with 21.3% of patients who had undergone ER immobilization (P < .0001). Similarly, 5.7% of operative patients had undergone a subsequent stabilization procedure at latest follow-up compared with 11.3% of patients who had undergone ER immobilization (P = .0015). A higher rate of return to sports was found in the operative group (P < .05), but no other differences were found between groups. CONCLUSION: Patients undergoing arthroscopic treatment for primary anterior glenohumeral dislocation with arthroscopic stabilization can be expected to experience significantly lower rates of recurrent instability and subsequent stabilization procedures compared with patients undergoing ER immobilization.

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.

Non-operative management of shoulder osteoarthritis: Current concepts.

Glenohumeral osteoarthritis (OA) is one of the most common causes of shoulder pain. Conservative treatment options include physical therapy, pharmacological therapy, and biological therapy. Patients with glenohumeral OA present shoulder pain and decreased shoulder range of motion (ROM). Abnormal scapular motion is also seen in patients as adaptation to the restricted glenohumeral motion. Physical therapy is performed to (1) decrease pain, (2) increase shoulder ROM, and (3) protect the glenohumeral joint. To decrease pain, it should be assessed whether the pain appears at rest or during shoulder motion. Physical therapy may be effective for motion pain rather than rest pain. To increase shoulder ROM, the soft tissues responsible for the ROM loss need to be identified and targeted for intervention. To protect the glenohumeral joint, rotator cuff strengthening exercises are recommended. Administration of pharmacological agents is the major part next to physical therapy in the conservative treatment. The main aim of pharmacological treatment is the reduction of pain and diminution of inflammation in the joint. To achieve this aim, non-steroidal anti-inflammatory drugs are recommended as first-line therapy. Additionally, the supplementation of oral vitamin C and vitamin D can help to slow down cartilage degeneration. Depending on the individual comorbidities and contraindications, sufficient medication with good pain reduction is thus possible for each patient. This interrupts the chronic inflammatory state in the joint and, in turn, enables pain-free physical therapy. Biologics such as platelet-rich plasma, bone marrow aspirate concentrate, and mesenchymal stem cells have gathered increased attention. Good clinical outcomes have been reported, but we need to be aware that these options are helpful in decreasing shoulder pain but neither stopping the progression nor improving OA. Further evidence of biologics needs to be obtained to determine their effectiveness. In athletes, a combined approach of activity modification and physical therapy can be effective. Oral medications can provide patients with transient pain relief. Intra-articular corticosteroid injection, which provides longer-term effects, must be used cautiously in athletes. There is mixed evidence for the efficacy of hyaluronic acid injections. There is still limited evidence regarding the use of biologics.

Anatomic glenohumeral arthroplasty: State of the art.

Anatomical total shoulder arthroplasty in its modern form where it reproduces the normal shoulder has been utilized clinically for more than half a century. As the technology and the designs have changed to recreate the humeral and glenoid sides of the joint, the sophistication of design has resulted in the growing number of cases annually worldwide. This increase is due in part to the increasing number of indications that the prosthesis can treat with successful results. On the humeral side, there have been design changes to better reflect the proximal humeral anatomy, and humeral stems are increasingly placed safely without cement. Platform systems which allow conversion of a failed arthroplasty to a reverse configuration without stem extraction is another design change. Similarly, there has been increasing utilization of short stem and stemless humeral components. Extensive experience with shorter stem and stemless devices, however, has yet to demonstrate the purported advantages of these devices, as recent studies have demonstrated equivalent blood loss, fracture rates, operative times, and outcome scores. Easier revision with these shorter stems remains to be definitively established, with only one study comparing the ease of revision between stem types. On the glenoid side, hybrid cementless glenoids, inlay glenoids, cementless all-polyethylene glenoids, and augmented glenoids have all been investigated; however, the indications for these devices remain unclear. Lastly, innovative surgical approaches to implanting shoulder arthroplasty and the use of patient specific guides and computerized planning, while interesting concepts, still await validation before they are utilized on a widespread basis. While reverse shoulder arthroplasty has been increasingly used to reconstruct the arthritic shoulder, anatomic glenohumeral replacement maintains a significant role in the armamentarium of the shoulder surgeon.

On-Field Sports Emergencies: Preparation and Readiness.

The foundation of preventing and treating an on-field emergency is preparation and readiness. The sideline medical team should coordinate the utilization of an emergency action plan (EAP). A successful EAP is accomplished through attention to detail, rehearsal, and self-assessments. Every EAP should include site-specific implementation, personnel, equipment, communication, transportation, venue location, emergency care facilities, and documentation. Improvements and advancements can be made to the EAP by self-evaluation after each on-field emergency and yearly reviews. A competent sideline emergency medical team can enjoy the competition while being ready to respond to a catastrophic on-field emergency.

The Collapsed Athlete: General Principles.

The collapsed athlete encompasses multiple critical and noncritical pathologic conditions, management of which highly depends on the elements of presentation of an athlete, the environment in which the athlete presents, and the key history elements leading to the collapse. Early identification of an unresponsive/pulseless athlete with basic life support/CPR, AED use, and EMS activation is key, with the addition of early hemorrhage control in acute traumatic injuries. The initiation of a focused history and physical examination is critical to rule out life-threatening causes of collapse and to guide initial management and disposition.

Program and Faculty Reputation Are Valued Most by Applicants to Orthopaedic Sports Medicine Fellowships.

Purpose: To determine the top orthopaedic surgery sports medicine fellowship programs in the United States and the most important aspects of fellowship programs as perceived by applicants. Methods: An anonymous survey was distributed via e-mail and text message to all current/former orthopaedic surgery residents who applied to one particular orthopaedic sports medicine fellowship program during the 2017-2018 through 2021-2022 application cycles. The survey asked applicants to rank what they considered to be the top-10 orthopaedic sports medicine fellowship programs in the United States before and after completion of their application cycle, based on operative and nonoperative experience, faculty, game coverage, research, and work-life balance. Final rank was calculated by awarding 10 points for a first-place vote, 9 points for a second-place vote, etc., with total number of points used to determine final ranking for each program. Secondary outcomes included rates of applying to perceived top-10 programs, relative importance of different fellowship program aspects, and preferred type of practice. Results: Seven-hundred sixty-one surveys were distributed with 107 applicants responding (14% response rate). Applicants voted the top orthopaedic sports medicine fellowships programs to be: (1) Steadman Philippon Research Institute, (2) Rush University Medical Center, and (3) Hospital for Special Surgery, both before and following the application cycle. When ranking fellowship program aspects, faculty members and fellowship reputation were most likely to be ranked highest in importance. Conclusions: This study demonstrates that most orthopaedic sports medicine fellowship applicants highly valued program reputation and faculty members when choosing a fellowship program and that the application/interview process did not have a substantial effect on how individuals perceived the top programs. Clinical Relevance: The findings of this study are important for residents applying to orthopaedic sports medicine fellowships and may have implications on fellowship programs and future application cycles.

Effects of Running on the Development of Knee Osteoarthritis: An Updated Systematic Review at Short-Term Follow-up.

Background: Some studies have suggested that running increases the risk of knee osteoarthritis (OA), while others believe it serves a protective function. Purpose: To perform an updated systematic review of the literature to determine the effects of running on the development of knee OA. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was performed by searching the PubMed, Cochrane Library, and Embase databases to identify studies evaluating the effect of cumulative running on the development of knee OA or chondral damage based on imaging and/or patient-reported outcomes (PROs). The search terms used were "knee AND osteoarthritis AND (run OR running OR runner)." Patients were evaluated based on plain radiographs, magnetic resonance imaging (MRI), and PROs (presence of knee pain, Health Assessment Questionnaire-Disability Index, and the Knee injury and Osteoarthritis Outcome Score). Results: Seventeen studies (6 level 2 studies, 9 level 3 studies, and 2 level 4 studies), with 7194 runners and 6947 nonrunners, met the inclusion criteria. The mean follow-up time was 55.8 months in the runner group and 99.7 months in the nonrunner group. The mean age was 56.2 years in the runner group and 61.6 years in the nonrunner group. The overall percentage of men was 58.5%. There was a significantly higher prevalence of knee pain in the nonrunner group (P < .0001). Although 1 study found a significantly higher prevalence of osteophytes in the tibiofemoral (TF) and patellofemoral (PF) joints within the runner group, multiple studies found no significant differences in the prevalence of radiographic knee OA (based on TF/PF joint-space narrowing or Kellgren-Lawrence grade) or cartilage thickness on MRI between runners and nonrunners (P > .05). One study found a significantly higher risk of knee OA progressing to total knee replacement among nonrunners (4.6% vs 2.6%; P = .014). Conclusion: In the short term, running is not associated with worsening PROs or radiological signs of knee OA and may be protective against generalized knee pain.

Patients With Knee Osteoarthritis Who Receive Platelet-Rich Plasma or Bone Marrow Aspirate Concentrate Injections Have Better Outcomes Than Patients Who Receive Hyaluronic Acid: Systematic Review and Meta-analysis.

PURPOSE: To systematically review the literature to compare the efficacy and safety of platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and hyaluronic acid (HA) injections for the treatment of knee osteoarthritis (OA). METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I studies that compared the clinical efficacy of at least 2 of the following 3 injection therapies: PRP, BMAC, and HA for knee OA. The search phrase used was knee AND osteoarthritis AND randomized AND ("platelet rich plasma" OR "bone marrow aspirate" OR "hyaluronic acid"). Patients were primarily assessed based on patient-reported outcome scores (PROs) including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) score. RESULTS: Twenty-seven studies (all Level I) met inclusion criteria, including 1,042 patients undergoing intra-articular injection(s) with PRP (mean age 57.7 years, mean follow-up 13.5 months), 226 patients with BMAC (mean age 57.0 years, mean follow-up 17.5 months), and 1,128 patients with HA (mean age 59.0 years, mean follow-up 14.4 months). Nonnetwork meta-analyses demonstrated significantly better postinjection WOMAC (P < .001), VAS (P < .01), and Subjective IKDC scores (P < .001) in patients who received PRP compared with patients who received HA. Similarly, network meta-analyses demonstrated significantly better postinjection WOMAC (P < .001), VAS (P = .03), and Subjective IKDC (P < .001) scores in patients who received BMAC compared with patients who received HA. There were no significant differences in postinjection outcome scores when comparing PRP with BMAC. CONCLUSIONS: Patients undergoing treatment for knee OA with PRP or BMAC can be expected to experience improved clinical outcomes when compared with patients who receive HA. LEVEL OF EVIDENCE: Level I, meta-analysis of Level I studies.

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).

Shoulder Stabilization Versus Immobilization for First-Time Anterior Shoulder Dislocation: A Systematic Review and Meta-analysis of Level 1 Randomized Controlled Trials.

BACKGROUND: Multiple studies have compared redislocation rates after stabilization and immobilization for patients experiencing a traumatic, first-time anterior shoulder dislocation (ASD). PURPOSE: To systematically review the literature to compare rates of recurrent instability and subsequent instability surgery in patients undergoing treatment for a first-time ASD with surgical stabilization versus shoulder immobilization. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 1. METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify level 1 randomized studies that compared outcomes of surgical stabilization versus immobilization for treatment of primary ASD. The following search phrase was used: (glenohumeral OR anterior shoulder) AND (conservative OR nonoperative OR nonsurgical OR physiotherapy) AND (Bankart OR repair OR stabilization OR surgical OR surgery OR arthroscopic OR arthroscopy) AND (instability OR dislocation). Patients with soft tissue disruption alone as well as those with additional minor bony lesions (Hill-Sachs, Bankart) were included. Recurrent instability and subsequent instability surgery rates, the Western Ontario Shoulder Instability Index (WOSI), and range of motion were evaluated. RESULTS: A total of 5 studies met inclusion criteria, including 126 patients undergoing surgical stabilization (mean age, 23.6 years; range, 15.0-39.0 years) and 133 patients undergoing treatment with sling immobilization only (mean age, 23.1 years; range, 15.0-31.0 years). Mean follow-up was 59.7 months. Overall, 6.3% of operative patients experienced recurrent instability at latest follow-up compared with 46.6% of nonoperative patients (P < .00001). Similarly, 4.0% of operative patients underwent a subsequent instability surgery compared with 30.8% of nonoperative patients (P < .00001). These same trends were demonstrated when data were isolated to nonoperative patients immobilized in internal rotation. When comparing the operative and nonoperative groups at latest follow-up, 1 study found significantly improved WOSI scores among operative patients (P = .035) and 1 study found significantly improved abducted external rotation in nonoperative patients (P = .02). CONCLUSION: Patients, particularly active men in their 20s and 30s, undergoing treatment for a first-time ASD with a surgical stabilization procedure can be expected to experience significantly lower rates of recurrent instability and a significantly decreased need for a future stabilization procedure when compared with patients treated nonoperatively.

Single- and Double-Loaded All-Suture Anchor Repairs of Anteroinferior Labral Tears Are Biomechanically Similar in a Cadaveric Shoulder Model.

Purpose: To compare the biomechanical strength of single- versus double-loaded all-suture constructs in an anteroinferior glenoid labral repair. Methods: Anteroinferior labral lesions were created on 6 matched pairs of cadaveric shoulder specimens. Each shoulder in a matched pair was randomized to either receive capsulolabral repair with 3 single-loaded all-suture anchors or 3 double-loaded all-suture anchors. Immediately following capsulolabral repair, the specimens underwent mechanical testing, which included cyclic testing (5 N to 50 N for 500 cycles) and load-to-failure testing (rate of 15 mm/min). The gap formation between the repaired labrum and glenoid (measured at 1, 25, 100, and 500 cycles), the load at 2-mm gap formation, the maximum load at failure and the method of failure were recorded. Data were analyzed with paired Student t tests and Bonferroni correction factor. Results: The single and double all-suture constructs did not differ significantly in gap formation at any number of cycles, load to 2-mm gap formation (P = .75), or maximum load to failure (P = .46) between the 2 groups. Conclusions: In this study, single-loaded and double-loaded all-suture anchor constructs demonstrated comparable biomechanical performance and did not significantly differ in gap formation, load to 2-mm gap formation, or maximum load to failure when used in the capsulolabral repair of anteroinferior glenoid labral tears in human cadaveric specimens. Clinical Relevance: Although studies have evaluated the biomechanical properties of various arthroscopic labral stabilization techniques, the biomechanical properties of all-suture anchors with regard to labral stabilization are not well understood.

Autograft and Nonirradiated Allograft for Anterior Cruciate Ligament Reconstruction Demonstrate Similar Clinical Outcomes and Graft Failure Rates: An Updated Systematic Review.

Purpose: To perform an updated systematic review comparing the clinical outcomes of autograft versus nonirradiated allograft for anterior cruciate ligament reconstruction (ACLR). Methods: A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, the Cochrane Library, and Embase to identify comparative studies directly comparing outcomes of primary ACLR with autograft versus nonirradiated allograft with a minimum 2-year follow-up. The search terms used were: "anterior cruciate ligament" AND autograft AND allograft AND (irradiation OR non-irradiated). Patients were evaluated based on graft failure rates, the Objective International Knee Documentation Committee (IKDC) score, anteroposterior laxity, and patient-reported outcomes (Subjective IKDC score, the visual analog scale [VAS], the Cincinnati Knee Rating System, Lysholm, and Tegner scores). Risk of bias was assessed using the ROBINS-I and Cochrane Collaboration's risk of bias tool for non-randomized and randomized studies, respectively. Results: Sixteen studies (3 Level I, 7 Level II, 6 Level III) met inclusion criteria, including a total of 15,502 patients undergoing ACLR with autograft and 1,577 with nonirradiated allograft. The average follow-up ranged from 24.0 to 132.0 months. Graft failure ranged from 0% to 9.4% of patients in the autograft group and 0% to 26.5% in the allograft group. Two studies showed greater failure rates among younger patients in the allograft group. There were no significant differences between the Objective IKDC score, anteroposterior laxity, or patient-reported outcomes between the groups within any of the included studies (P > .05). Conclusions: Autograft and nonirradiated allograft for primary ACLR demonstrate similar patient-reported outcomes and graft failure rates. Level of Evidence: III, systematic review of level I-III studies.