Bone morphology is one feature that contributes to knee kinematics. The geometry of the tibia and femur vary across individuals, and these differences can influence the risk of anterior cruciate ligament (ACL) injury and of failure after isolated ACL reconstruction. There has been renewed interest in lateral extra-articular stabilization procedures to supplement an ACL reconstruction, although which patients benefit most from these procedures remains unclear. This article reviews the impact of bone morphology on knee kinematics, including tibial slope, depth of the medial tibial plateau, intercondylar notch shape, tibial eminence volume, and sphericity of the femoral condyles.

Purpose of review

This review examines the relationship between the baseball pitching motion and the kinetic chain. The goal was to determine the underlying causes of a deficiency in throwing mechanics throughout a throwing motion, and to provide an evidence-based approach on how to prevent injuries caused by a lack of proper mechanics. In doing so, we sought to provide a warm-up strategy that can be added to every baseball player's daily on-field routine that is tailored to each phase of the throwing motion.

Recent findings

To help minimize the risk of injury to overhead throwing athletes, a thorough understanding of the throwing motion is critical. Throwing a ball places extreme stress on the body, notably the shoulder and elbow joints. With a clear understanding of the biomechanics of throwing, we can develop an injury prevention routine to minimize unnecessary stresses throughout the kinetic chain. The throwing cycle is a complex motion that places various stresses throughout the thrower's body, from the ankle to the core, and from the back to the shoulder and elbow. A thorough understanding of the mechanics of this motion, along with specific exercises to target the specific actions of each phase, may allow for throwers, regardless of their age and experience, to minimize injury risk.

BACKGROUND: Poor socioeconomic status (SES) is consistently associated with poor quality of health care, particularly in the field of orthopedics. Expanding insurance coverage has created a larger patient population by specifically making health care more accessible, translating to greater demand for care in the low-SES population. The purpose of this article is to provide a scoping review of literature observing access and outcomes of rotator cuff repair surgery among low-SES populations. METHODS: We performed a systematic review of articles using PubMed, Embase, and EBSCO (May 2021) from 2010 onward. Peer-reviewed articles that recorded at least one SES measure specific to patients who underwent rotator cuff repair from the United States were included. SES measures were methodically defined as income, occupation, employment, education, and race. All data that aligned with these SES measures were extracted. RESULTS: Of the 1009 titles reviewed, 109 studies were screened by abstract, 23 were reviewed in full, and 7 studies met criteria for inclusion. Of the 5 studies investigating access, all 5 found disparities among postoperative physical therapy, orthopedic consult, and surgery, using Medicaid status as a proxy for income in addition to other income measures. Of the 3 studies analyzing outcomes, 2 found that low-SES patients had worse pain and function, again based on Medicaid status and other income measures. Education did not have a significant impact on outcomes, as per the 1 study that included it. No studies included measures of occupation or employment. CONCLUSION: Patients of low SES face reduced access to cuff repair care and worse associated outcomes, despite federal and state government efforts to reduce health care disparity through health care reform. The small nature of this review reflects how measures of SES are often not examined in rotator cuff repair studies.

Background

Athletes in the Women's National Basketball Association (WNBA) and National Basketball Association (NBA) are subject to high injury rates given the physical demands of the sport. Comprehensive data regarding injury patterns and rates in these athletes are limited.

Purpose

To summarize available data on orthopaedic and sports medicine-related injuries through 2020 in professional female and male basketball players.

Study design

Systematic review; Level of evidence, 4.

Methods

A search was conducted using PubMed and Embase through April 5, 2020, to identify injury studies regarding WNBA and NBA players. Studies were included if the injury or surgery was considered a direct consequence of game play including musculoskeletal/orthopaedic, concussion, ophthalmologic, and craniomaxillofacial injuries. Systematic reviews, screening studies, or studies without sufficient WNBA or NBA player subgroup analysis were excluded.

Results

A total of 49 studies met inclusion criteria, 43 (87.8%) of which detailed musculoskeletal injuries. The lower extremity represented 63.3% of studies. A majority (59.2%) of studies were level 4 evidence. The source of data was primarily comprehensive online search (n = 33; 67.3%), followed by official databases (n = 11; 22.4%). Only 3 studies concerned WNBA athletes compared with 47 that concerned NBA athletes. The lowest return-to-play rates were cited for Achilles tendon repairs (61.0%-79.5%). Variability in return-to-play rates existed among studies even with similar seasons studied.

Conclusion

The majority of literature available on orthopaedic and sports medicine-related injuries of NBA and WNBA athletes is on the lower extremity. The injuries that had the greatest effect on return to play and performance were Achilles tendon ruptures and knee cartilage injuries treated using microfracture. The reported outcomes are limited by heterogeneity and overlapping injury studies. There are limited available data on WNBA injuries specifically.

The long head of the biceps is a frequent pain generator in the shoulder. Tendinopathy of the long head of the biceps may be treated with biceps tenodesis. There has been great debate about the optimal technique for biceps tenodesis, without a clear distinction between different techniques. Biceps tenodesis fixation may include interference fixation, suspensory fixation, all-suture anchors, and soft tissue fixation. In this technical note, we describe an all-arthroscopic onlay suprapectoral biceps tenodesis with an all-suture anchor.

Background

Superior labral anterior-posterior (SLAP) tears can be associated with pain and shoulder dysfunction. Relatively little is known about the age-related prevalence of SLAP tears.

Purpose

To investigate the age-related prevalence of imaging-diagnosed SLAP tears in a heterogeneous grouping of shoulder conditions in a large cohort at a single institution with multiple blinded reviewers.

Study design

Cross-sectional study; Level of evidence, 3.

Methods

A total of 281 shoulder magnetic resonance imaging (MRI) scans obtained over 8 months were reviewed by a musculoskeletal radiologist and an orthopaedic surgeon. The mean ± SD age of the group was 49.6 ± 15.5 years, and 107 of the patients were female (38.1%). Patients were divided into 4 age groups: 35 years or younger, 36 to 50 years, 51 to 65 years, and older than 65 years. Statistical analyses were completed by use of the Fisher exact test to compare proportions of SLAP tears between age groups, odds ratios to determine the likelihood of having a SLAP tear in each age group, and a logistic regression to control for associated abnormalities.

Results

There was a significant diffference in the proportion of SLAP tears found on the MRIs for each age group (P < .001). Patients were significantly more likely to have SLAP tears if aged 51 to 65 years (66.7%; odds ratio [OR], 2.00; 95% CI, 1.27-3.15) and if older than 65 years (81.2%; OR, 4.31; 95% CI, 2.36-7.88). No increased prevalence was observed in patients aged 35 years or younger (47.5%; OR, 0.91; 95% CI, 0.55-1.50) or 36 to 50 years (51.8%; OR, 1.08; 95% CI, 0.70-1.67). Logistic regression demonstrated that age was the only significant predictor for having a SLAP tear (P < .001). Kappa values were 0.46 to 0.65 between reviewers, indicating moderate to substantial agreement.

Conclusion

An increasing prevalence of MRI-based SLAP tears was observed with increasing patient age. Patients older than 50 years were significantly more likely to have superior labral abnormalities regardless of other shoulder injury or disease.

PURPOSE OF REVIEW:Anterior cruciate ligament (ACL) injury is one of the most common ligamentous injuries suffered by athletes participating in cutting sports. A common misperception is that ACL reconstruction can prevent osteoarthritis (OA). The goal of this paper is to review and discuss the contributing factors for the development of OA following ACL injury. RECENT FINDINGS:There has been interesting new research related to ACL reconstruction. As understanding of knee biomechanics following ACL injury and reconstruction has changed over time, many surgeons have changed their surgical techniques to low anterior drilling to position their femoral tunnel in an attempt to place the ACL in a more anatomic position. Even with this change in the femoral tunnel position, 85% of knees following ACL reconstruction have abnormal tibial motion compared to contralateral non-injured knees. Studies have shown increases in inflammatory cytokines in the knee following ACL injury, and newer MRI sequences have allowed for earlier objective detection of degenerative changes to cartilage following injury. Recent studies have shown that injecting IL-1 receptor antagonist and corticosteroids can modulate the post-injury inflammatory cascade. ACL reconstruction does not prevent the development of OA but can improve knee kinematics and reduce secondary injury to the cartilage and meniscus. Advancements in imaging studies has allowed for earlier detection of degenerative changes in the knee, which has allowed researchers to study how new interventions can alter the course of degenerative change in the knee following ACL injury.

BACKGROUND: The purpose of this study was to develop a deep learning approach to automatically segment the scapular bone on magnetic resonance imaging (MRI) images and to compare the accuracy of these three-dimensional (3D) models with that of 3D computed tomography (CT). METHODS: Fifty-five patients with high-resolution 3D fat-saturated T2 MRI were retrospectively identified. The underlying pathology included rotator cuff tendinopathy and tears, shoulder instability, and impingement. Two experienced musculoskeletal researchers manually segmented the scapular bone. Five cross-validation training and validation splits were generated to independently train two-dimensional (2D) and 3D models using a convolutional neural network approach. Model performance was evaluated using the Dice similarity coefficient (DSC). All models with DSC > 0.70 were ensembled and used for the test set, which consisted of four patients with matching high-resolution MRI and CT scans. Clinically relevant glenoid measurements, including glenoid height, width, and retroversion, were calculated for two of the patients. Paired t-tests and Wilcoxon signed-rank tests were used to compare the DSC of the models. RESULTS: The 2D and 3D models achieved a best DSC of 0.86 and 0.82, respectively, with no significant difference observed. Augmentation of imaging data significantly improved 3D but not 2D model performance. In comparing clinical measurements of 3D MRI and CT, there was a mean difference ranging from 1.29 mm to 3.46 mm and 0.05° to 7.47°. CONCLUSION: We have presented a fully automatic, deep learning-based strategy for extracting scapular shape from a high-resolution MRI scan. Further developments of this technology have the potential to allow for surgeons to obtain all clinically relevant information from MRI scans and reduce the need for multiple imaging studies for patients with shoulder pathology.

PURPOSE OF REVIEW:Over the past decade, our understanding of the biomechanics of the reverse total shoulder arthroplasty (RTSA) has advanced, resulting in design adjustments, improved outcomes, and expanding indications. The purpose of this review is to summarize recent literature regarding the biomechanics of RTSA and the evolving indications for its use. RECENT FINDINGS:While Grammont's principles of RTSA biomechanics remain pillars of contemporary designs, a number of modifications have been proposed and trialed in later generations to address complications such as impingement and glenoid failure. Clinical and biomechanical literature suggest that less medialized, more inferior glenospheres result in less impingement and notching. On the humerus, a more vertical neck cut is associated with less impingement. Indications for RTSA continue to expand beyond the classic indication of cuff tear arthropathy (CTA). Patients without a functional cuff but no arthritis now have a reliable option in the RTSA. RTSA has also replaced hemiarthroplasty as the implant of choice for displaced three- and four-part proximal humerus fractures in the elderly. Finally, updated design options and modular components now allow for treatment of glenoid bone loss, failed arthroplasty, and proximal humerus tumors with RTSA implants. Reverse total shoulder arthroplasty design has been modernized on both the glenoid and humerus to address biomechanical challenges of early implants. As outcomes improve with these modifications, RTSA indications are growing to address complex bony pathologies such as tumor and bone loss. Longitudinal follow-up of patients with updated designs and novel indications is essential to judicious application of RTSA technology.