Artificial Intelligence Large Language Models Address Anterior Cruciate Ligament Reconstruction: Superior Clarity and Completeness by Gemini Compared to ChatGPT-4 in Response to American Academy of Orthopedic Surgeons Clinical Practice Guidelines.

PURPOSE: To assess the ability of ChatGPT-4 and Gemini to generate accurate and relevant responses to the 2022 American Academy of Orthopaedic Surgeons (AAOS) clinical practice guidelines for ACLR. METHODS: Responses from ChatGPT-4 and Gemini to prompts derived from all 15 AAOS guidelines were evaluated by seven fellowship trained orthopedic sports medicine surgeons using a structured questionnaire assessing five key characteristics on a scale from 1-5. The prompts were categorized into three areas: Diagnosis and Preoperative Management, Surgical Timing and Technique, and Rehabilitation and Prevention. Statistical analysis included mean scoring, standard deviation, and two-sided t-tests to compare the performance between the two LLMs. Scores were then evaluated for inter-rater reliability (IRR). RESULTS: Overall, both LLMs performed well with means scores > 4 for the five key characteristics. Gemini demonstrated superior performance in overall clarity (4.848 ± 0.36 vs 4.743 ± 0.481, p = 0.034), but all other characteristics demonstrated non-significant differences (p = >0.05). Gemini also demonstrated superior clarity in the surgical timing and technique (p= 0.038) as well as the prevention and rehabilitation (p= 0.044) sub-categories. Additionally, Gemini had superior performance completeness scores in the rehabilitation and prevention sub-category (p= 0.044), but no statistically significant differences were found amongst the other sub-categories. The overall IRR was found to be 0.71 (moderate). CONCLUSION: Both Gemini and ChatGPT-4 demonstrate an overall good ability to generate accurate and relevant responses to question prompts based on the 2022 AAOS clinical practice guidelines for ACLR. However, Gemini demonstrated superior clarity in multiple domains in addition to superior completeness for questions pertaining to rehabilitation and prevention. CLINICAL RELEVANCE: The current study addresses a current gap in the LLM and ACLR literature by comparing the performance of ChatGPT-4 to Gemini, which is growing in popularity with more than 300 million individual uses in May 2024 alone. Moreover, the results demonstrated superior performance of Gemini in both clarity and completeness, which are critical elements of a tool being used by patients for educational purposes. Additionally, the current study uses question prompts based on the AAOS CPG which may be used as a method of standardization for future investigations on performance of LLM platforms. For these reasons, the authors believe that the results of the current study would be of interest to both the readership of Arthroscopy and patients, alike.

The Statistical Fragility of Lateral Extra-articular Tenodesis Research: A Systematic Review.

Background: A P value of <.05 is often used to denote statistical significance; however, in many scenarios, this threshold is vulnerable to a small number of outcome reversals. This study joins a body of studies within the orthopaedic literature that evaluate the statistical fragility of existing research via metrics such as fragility index (FI) and fragility quotient (FQ). Purpose/Hypothesis: The purpose of this study was to investigate the statistical fragility of randomized controlled trials (RCTs) and comparative studies on the topic, given the resurgent interest in lateral extra-articular tenodesis (LET) to augment primary or revision anterior cruciate ligament reconstruction (ACLR). It was hypothesized that the outcomes reported in these studies would be statistically fragile. Study Design: Systematic review; Level of evidence, 4. Methods: Comparative studies and RCTs regarding LET as an adjunct procedure to ACLR published between 2000 and 2022 were analyzed. Descriptive characteristics, dichotomous outcomes, and continuous outcomes were extracted. The FI and continuous FI (CFI) were calculated by the number of event reversals to change significance; the FQ and continuous FQ (CFQ) were calculated to normalize the fragility metrics per sample size. Results: Of 455 studies screened, 29 studies were included (9 RCTs, 20 comparative); 79.3% of included studies were published after 2020. A total of 48 dichotomous and 265 continuous outcomes were analyzed. The median FI was 9.0 (IQR, 7.0-13.3), with FQ of 0.1 (IQR, 0.04-0.17); the median CFI was 7.8 (IQR, 4.2-19.6), with CFQ of 0.12 (IQR, 0.08-0.19). The FQ and CFQ for studies on LET with revision ACLR were larger (0.117 and 0.113, respectively) than those focused on primary ACLR (0.042 and 0.095, respectively). Conclusion: Studies focused on LET with primary ACLR were more fragile than those on LET with revision, which suggests that further research on the indications for LET with primary ACLR is necessary. Future orthopaedic comparative research should include fragility metrics alongside traditional P values.

Biomechanics and Pathoanatomy of Posterior Shoulder Instability.

Posterior glenohumeral instability represents a wide spectrum of pathoanatomic processes. A key consideration is the interplay between the posterior capsulolabral complex and the osseous anatomy of the glenoid and humeral head. Stability is dependent upon both the presence of soft tissue pathology (eg, tears to the posteroinferior labrum or posterior band of the inferior glenohumeral ligament, glenoid bone loss, reverse Hill Sachs lesions, and pathologic glenoid retroversion or dysplasia) and dynamic stabilizing forces. This review highlights unique pathoanatomic features of posterior shoulder instability and associated biomechanics that may exist in patients with posterior glenohumeral instability.

Epidemiology of Testicular Trauma in Sports: Analysis of the National Electronic Injury Surveillance System Database.

BACKGROUND: The epidemiology of testicular trauma in sports on a national scale has not been well studied. Timely management and treatment after testicular trauma is critical to avoid serious, long-term ramifications of mismanagement. OBJECTIVE: The aim was to analyze trends in sports-related testicular trauma based on specific sports and patient demographic characteristics over time. METHODS: The National Electronic Injury Surveillance System was queried for emergency department cases between 2012 and 2021 with injuries in the pubic region related to 10 commonly played sports. Variables examined included patient age, race, disposition, and sport using incidence rate, incidence rate ratios, and χ2 analysis. RESULTS: There were an estimated 28,844 emergency department cases of sports-related testicular trauma between 2012 and 2021. Young patients, aged between 10 and 14 years and 15 and 19 years, accounted for most cases, and results of χ2 analysis showed a significant difference in incidence based on age group (p < 0.01). Most injuries occurred while athletes played basketball, football, and soccer (73.6%). CONCLUSIONS: Sports-related testicular trauma injury rates remained steady between 2012 and 2021, which suggests greater efforts are necessary to reduce the incidence of sports-related testicular trauma. Education efforts should focus on 10- to 19-year-olds because they have the highest incidence. Given the high incidence in sports like basketball and soccer compared with football and lacrosse, testicular trauma seems to be a risk for athletes competing both recreationally and competitively.

Social and Demographic Health Disparities in Shoulder and Elbow Surgery.

BACKGROUND: Racial and ethnic health disparities are important factors that contribute to outcomes in orthopedic surgery. With the increasing rates of common shoulder surgeries being performed, understanding all factors that contribute to patient outcomes is essential. There are several key socioeconomic and demographic factors, including insurance status, ethnicity, and Race, which have been implicated to impact both access to high-quality shoulder and elbow care and outcomes following shoulder and elbow surgery. In this review article, we seek to highlight the literature pertaining to social and demographic disparities in shoulder and elbow surgery for the purpose of providing policy makers and clinicians key information to optimize the equitable delivery of high-quality medical care to patients of all socioeconomic backgrounds. METHODS: A literature review of PubMed was conducted using several keywords with defined inclusion and exclusion criteria. RESULTS: A total of 22 articles were included across shoulder arthroplasty, rotator cuff repair, shoulder instability, and elbow arthroplasty. Multiple disparities were identified in the literature across Race, ethnicity, insurance status, and social determinants of health. CONCLUSIONS: Our search of the literature demonstrated significant disparities in shoulder and elbow surgeries, showing that racial, ethnic, and socioeconomic factors adversely affect patient outcomes due to decreased access quality care. To improve equity, recommendations include shifting care to high-volume and outpatient centers and increasing geographical diversity and access to surgical and rehabilitative care.

Readability and Reliability of Online Information Regarding Patellar Instability.

BACKGROUND: Assessment of readability and reliability of online resources for orthopedic patients is an area of growing interest, but there is currently limited reporting on this topic for patellar instability (PI) and medial patellofemoral ligament reconstruction (MPFLR). METHODS: Utilizing the Searchresponse.io dataset, we analyzed inquiries related to PI and MPFLR. Readability and reliability were assessed using the Automated Reading Index, Flesch Reading Ease, and the JAMA benchmark criteria. RESULTS: Analysis of 363 frequently asked questions from 130 unique websites revealed a predominant interest in fact-based information. Readability assessments indicated that the average grade level of the resources was significantly higher than the 6th grade level and reliability varied between resources. CONCLUSION: Although the internet is an easily accessible resource, we demonstrate that PI and MPFLR resources are written at a significantly higher reading level than is recommended, and there is inconsistent reliability amongst resources with medical practice websites demonstrating the lowest reliability.

Association of Vitamin D Deficiency With Distal Biceps Injury: A Retrospective Analysis of 336,320 Patients.

BACKGROUND: This study explores the association between vitamin D deficiency and distal biceps tendon injuries, illustrating that, although vitamin D deficiency is associated with prolonged hospital stays and various musculoskeletal problems, its connection to distal biceps tendon injuries is unknown. HYPOTHESIS: Vitamin D deficiency is associated with an elevated risk of distal biceps injury but not with increased rates of subsequent surgery or revision surgery. STUDY DESIGN: Case-control study. LEVEL OF EVIDENCE: Level 3. METHODS: A 1:1 matched retrospective comparative study of 336,320 vitamin-D-deficient patients was performed using PearlDiver data (between January 1, 2011 and October 31, 2018). Cohorts, with a mean age of 55.7 ± 13.2 years, underwent multivariate logistic regression to calculate distal biceps tendon injury and surgical repair incidence according to age and sex, while controlling for demographics and comorbidities. RESULTS: The 1-year incidence of distal biceps tendinopathy in vitamin-D-deficient patients was 118 per 100,000 person-years (95% CI) compared with 44.3 per 100,000 person-years in matched controls. Male patients with vitamin D deficiency were at a greater risk for distal biceps tendinopathy after 1 and 2 years (adjusted odds ratio [aOR] = 2.81, 2.08-3.83; aOR = 2.80, 2.21-3.56). Female patients were also at a greater risk after both years (aOR = 1.69, 1.27-2.27; aOR = 1.57, 1.26-1.96). Vitamin D deficiency was not associated with an elevated risk of surgical repair or revision surgery. CONCLUSION: In a nationwide cohort, a diagnosis of vitamin D deficiency elevated the risk of distal biceps tendinopathy but did not raise the rate of surgical repair or revision. As a result, prevention strategies in the form of vitamin supplementation should be increased for athletes.Clinical Relevance: These findings emphasize the clinical relevance of monitoring vitamin D levels in patients at risk for musculoskeletal injuries, and providing adequate care to those involved in high-demand physical activities.Strength of Recommendation: B.

Alpha-2-Macroglobulin Attenuates Posttraumatic Osteoarthritis Cartilage Damage by Inhibiting Inflammatory Pathways With Modified Intra-articular Drilling in a Yucatan Minipig Model.

BACKGROUND: Posttraumatic osteoarthritis (PTOA) arises secondarily to joint trauma and is driven by catabolic inflammatory pathways. Alpha-2-macroglobulin (α2M) is a naturally occurring proteinase inhibitor found in human serum and synovial fluid that binds proteases as well as proinflammatory cytokines involved in the pathogenesis of PTOA. PURPOSE: (1) To investigate the therapeutic potential of intra-articular α2M injections during the acute stages of PTOA by inhibiting inflammatory pathways driven by the cytokines expressed by the synovium in a large preclinical Yucatan minipig model and (2) to determine if 3 intra-articular α2M injections have greater chondroprotective effects compared with 1 intra-articular injection. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 48 Yucatan minipigs were randomized into 4 groups (n = 12 each): (1) modified intra-articular drilling (mIAD) and saline (mIAD + saline), (2) mIAD and 1 intra-articular α2M injection (mIAD +α2M-1), (3) mIAD and 3 α2M injections (mIAD +α2M-3), and (4) sham control. Surgical hindlimbs were harvested at 15 weeks after surgery. Cartilage degeneration, synovial changes, inflammatory gene expression, and matrix metalloproteinase levels were evaluated. Gait asymmetry was measured before and after surgery using a pressure-sensing walkway system. RESULTS: Macroscopic lesion areas and microscopic cartilage degeneration scores were lower in the mIAD +α2M-1 and mIAD +α2M-3 groups compared with the mIAD + saline group (P < .05) and similar to those in the sham group (P > .05). Synovial membrane scores of the mIAD +α2M-1 and mIAD +α2M-3 groups were lower than that of the mIAD + saline group (P < .05) and higher than that of the sham group (P < .05). Interleukin-1 beta, nuclear factor kappa B, and tumor necrosis factor alpha mRNA expression in the synovium and matrix metalloproteinase-1 levels in synovial fluid were significantly lower in the mIAD +α2M-1 and mIAD +α2M-3 groups compared with the mIAD + saline group (P < .05). No significant differences were observed between the mIAD +α2M-1 and mIAD +α2M-3 groups for all measured outcomes. There were early changes in gait (P < .05) between preoperative and postoperative time points for the mIAD + saline, mIAD +α2M-1, and mIAD +α2M-3 groups that normalized by 15 weeks. CONCLUSION: Animals receiving early α2M treatment exhibited less cartilage damage, milder synovitis, and lower inflammation compared with animals with no α2M treatment. These results exemplify the early anti-inflammatory effects of α2M and provide evidence that intra-articular α2M injections may slow the progression of PTOA. CLINICAL RELEVANCE: In patients presenting with an acute joint injury, an early intervention with α2M may have the potential to reduce cartilage degeneration from catabolic pathways and delay the development of PTOA.

An Update on Emerging Techniques and Considerations in Revision Anterior Cruciate Ligament Reconstruction.

¼ The rate of primary anterior cruciate ligament reconstruction (ACLR) failure in at-risk populations remains unacceptably high and necessitates thorough evaluation of native alignment and concomitant injuries.¼ Posterior tibial slope of >12° is a substantial risk factor of ACLR failure and should be corrected through anterior closing wedge osteotomy.¼ Varus malalignment of >5° exacerbates stress on the ACL graft, increases ACLR failure risks, and should be considered for correction through high tibial osteotomy at the time of revision ACLR.¼ Injuries to the anterolateral ligamentous complex are prevalent in ACL ruptures, and high-risk patients have shown benefit from anterolateral ligament reconstruction or lateral extra-articular tenodesis in the revision setting.¼ Addressing posterolateral corner, collateral ligament, and meniscal injuries, during revision ACLR, is vital to mitigate increased graft forces and optimize knee stability and functional outcomes.

Structure and Function Are Not the Same: The Case for Restoring Mechanoreceptor Continuity Following Anterior Cruciate Ligament Injury.

Anterior cruciate ligament (ACL) injury, particularly in increasingly young and active adolescents, continues to pose a clinical challenge with re-injury rates reported as high as 30%. Evidence also suggests that current standard-of-care ACL reconstruction (ACLR) does not mitigate post-traumatic osteoarthritis (PTOA) risk. Bridge- enhanced ACL restoration (BEAR) is a recently developed and tested ACL surgery that promotes primary healing of the native ACL with excellent early results. BEAR has shown to reduce signs of early PTOA compared to ACLR in an animal model. Here, we describe a theoretical framework related to re-innervation that can clarify why the outcomes of ACLR and BEAR surgeries differ. We also discuss how ongoing and new challenges in determining return-to-sport readiness following the competing surgeries may differ, and how emerging imaging tools and measures of neuromuscular function may aid in clinical decision-making to decrease the likelihood of re-injury and PTOA risk.

Arm Injuries and Prevention Proficiency in High School Fastpitch Softball Players: A Survey of Players, Parents, and Coaches.

Arm injuries are common in youth fastpitch softball players. To characterize arm injuries and assess injury prevention knowledge, we administered a cross-sectional online survey and injury prevention quiz to high school fastpitch softball players, parents, and coaches. Associations between throwing habits and adverse arm outcomes were computed. Surveys were collected from 123 high school players, 59 parents, and 28 coaches, totaling 210 responses. Nearly half (48.8%) of players saw a doctor for arm pain. Riseball pitchers were less likely to undergo surgery than non-riseball pitchers (P = .008). Outfield/utility players trended toward more frequent arm pain compared to alternative position groups (P = .086). On injury prevention quizzes, players, parents, and coaches averaged scores of 56-65% correct, with players scoring below parents (P = .011) and coaches (P = .006). In conclusion, high school softball players frequently seek medical attention for arm pain, and injury prevention knowledge is consistently lacking.

Latest Advances in Chondrocyte-Based Cartilage Repair.

Chondrocyte-based cell therapy has been used for more than 30 years and is still considered to be a promising method of cartilage repair despite some limitations. This review introduces the latest developments of four generations of autologous chondrocyte implantation and current autologous chondrocyte products. The regeneration of cartilage from adult chondrocytes is limited by culture-induced dedifferentiation and patient age. Cartibeads is an innovative three-step method to produce high-quality hyaline cartilage microtissues, and it is developed from adult dedifferentiated chondrocytes with a high number of cell passages. In addition, allogeneic chondrocyte therapies using the Quantum hollow-fiber bioreactor and several signaling pathways involved in chondrocyte-based cartilage repair are mentioned, such as WNT signaling, the BMP-2/WISP1 pathway, and the FGF19 pathway.

Outcomes of arthroscopic stabilization for posterior shoulder instability: a systematic review.

BACKGROUND: Posterior shoulder instability makes up approximately 10% of all shoulder instability cases and its diagnosis and treatment is less well understood. Recently, however, there has been increased recognition of posterior instability and posterior stabilization. The purpose of this study was to systematically review the literature to ascertain the outcomes on arthroscopic stabilization of posterior shoulder instability. METHODS: Two independent reviewers conducted a systematic literature search based on PRISMA guidelines, utilizing the MEDLINE database. Studies were eligible for inclusion if they reported postoperative outcomes for posterior shoulder instability following arthroscopic stabilization. RESULTS: A total of 48 studies met inclusion criteria for review including 2307 shoulders. Majority of patients were male (83.3%), with an average age of 26.1 years and a mean follow-up of 46.8 months. The functional outcome score primarily utilized for postoperative assessment was the American Shoulder and Elbow Surgeons with an average of 84.77. Overall, 90.9% of patients reported being satisfied with their arthroscopic stabilization. Recurrent instability occurred in 7.4% of patients. The total revision rate was 5.2%. 16.6% of patients reported residual pain postoperatively. The rate of return to play was 86.4% with 68.0% of patients returning to play at the same or higher level of play. CONCLUSION: Arthroscopic stabilization of posterior shoulder instability resulted in good outcomes with high patient satisfaction and low rates of recurrent instability, revisions, and residual pain.

Kartogenin Induces Chondrogenesis in Cartilage Progenitor Cells and Attenuates Cell Hypertrophy in Marrow-Derived Stromal Cells.

INTRODUCTION: Kartogenin (KGN) is a synthetic small molecule that stimulates chondrogenic cellular differentiation by activating smad-4/5 pathways. KGN has been proposed as a feasible alternative to expensive biologic growth factors, such as transforming growth factor ß, which remain under strict regulatory scrutiny when it comes to use in patients. METHOD: This study reports the previously unexplored effects of KGN stimulation on cartilage- derived mesenchymal progenitor cells (CPCs), which have been shown to be effective in applications of cell-based musculoskeletal tissue regeneration. Our findings demonstrate that KGN treatment significantly increased markers of chondrogenesis, SOX9 and COL2 following 3-10 days of treatment in human CPCs. RESULT: KGN treatment also resulted in a significant dose-dependent increase in GAG production in CPCs. The same efficacy was not observed in human marrow-derived stromal cells (BM-MSCs); however, KGN significantly reduced mRNA expression of cell hypertrophy markers, COL10 and MMP13, in BM-MSCs. Parallel to these mRNA expression results, KGN led to a significant decrease in protein levels of MMP-13 both at 0-5 days and 5-10 days following KGN treatment. CONCLUSION: In conclusion, this study demonstrates that KGN can boost the chondrogenicity of CPCs and inhibit hypertrophic terminal differentiation of BM-MSCs.

Management of Bone Loss in Posterior Glenohumeral Shoulder Instability: Current Concepts.

¼ Posterior glenohumeral instability is relatively uncommon compared with anterior instability, but is becoming an increasingly recognized and surgically managed shoulder pathology.¼ Soft-tissue stabilization alone may not be sufficient in patients who present with substantial bone loss to the posterior glenoid and/or the anterior humeral head.¼ For posterior glenoid defects, posterior glenoid osteoarticular augmentation can be used, and posterior glenoid opening wedge osteotomy can be considered in cases of posterior instability with pathologic retroversion.¼ For humeral head lesions, several surgical treatment options are available including subscapularis transposition into the humeral head defect, autograft or allograft reconstruction, humeral rotation osteotomy, and shoulder arthroplasty.

Preoperative planning with three-dimensional CT vs. three-dimensional magnetic resonance imaging does not change surgical management for shoulder instability.

Background: This study aims to determine the effect of time and imaging modality (three-dimensional (3D) CT vs. 3D magnetic resonance imaging (MRI)) on the surgical procedure indicated for shoulder instability. The hypothesis is there will be no clinical difference in procedure selection between time and imaging modality. Methods: Eleven shoulder surgeons were surveyed with the same ten shoulder instability clinical scenarios at three time points. All time points included history of present illness, musculoskeletal exam, radiographs, and standard two-dimensional MRI. To assess the effect of imaging modality, survey 1 included 3D MRI while survey 2 included a two-dimensional and 3D CT scan. To assess the effect of time, a retest was performed with survey 3 which was identical to survey 2. The outcome measured was whether surgeons made a "major" or "minor" surgical change between surveys. Results: The average major change rate was 14.1% (standard deviation: 7.6%). The average minor change rate was 12.6% (standard deviation: 7.5%). Between survey 1 to the survey 2, the major change rate was 15.2%, compared to 13.1% when going from the second to the third survey (P = .68). The minior change rate between the first and second surveys was 12.1% and between the second to third interview was 13.1% (P = .8). Discussion: The findings suggest that the major factor related to procedural changes was time between reviewing patient information. Furthermore, this study demonstrates that there remains significant intrasurgeon variability in selecting surgical procedures for shoulder instability. Lastly, the findings in this study suggest that 3D MRI is clinically equivalent to 3D CT in guiding shoulder instability surgical management. Conclusion: This study demonstrates that there is significant variability in surgical procedure selection driven by time alone in shoulder instability. Surgical decision making with 3D MRI was similar to 3D CT scans and may be used by surgeons for preoperative planning.

Distal Tibial Allograft for the Treatment of Anterior Shoulder Instability With Glenoid Bone Loss: A Systematic Review and Meta-analysis.

BACKGROUND: The use of a distal tibial allograft (DTA) for reconstruction of a glenoid defect in anterior shoulder instability has grown significantly over the past decade. However, few large-scale clinical studies have investigated the clinical and radiographic outcomes of the DTA procedure. PURPOSE: To conduct a systematic review and meta-analysis of clinical studies with data on outcomes and complications in patients who underwent the DTA procedure for recurrent anterior shoulder instability with glenoid bone loss. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: A comprehensive search of major bibliographic databases was conducted for articles pertaining to the use of a DTA for the management of anterior shoulder instability with associated glenoid bone loss. Postoperative complications and outcomes were extracted and compiled in a meta-analysis. RESULTS: Of the 8 included studies with 329 total participants, the mean patient age was 28.1 ± 10.8 years, 192 (83.8%) patients were male, and the mean follow-up was 38.4 ± 20.5 months. The overall complication rate was 7.1%, with hardware complications (3.8%) being the most common. Partial graft resorption was observed in 36.5% of the participants. Recurrent subluxation was reported in 1.2% of the participants, and recurrent dislocation prompting a reoperation was noted in 0.3% of the participants. There were significant improvements in clinical outcomes, including American Shoulder and Elbow Surgeons score (40.9-point increase; P < .01), Single Assessment Numeric Evaluation (47.2-point increase; P < .01), Western Ontario Shoulder Instability Index (49.4-point decrease; P < .01), Disabilities of the Arm, Shoulder and Hand (20.0-point decrease; P = .03), and visual analog scale (2.1-point decrease; P = .05). Additionally, postoperative shoulder range of motion significantly increased from baseline values. CONCLUSION: The DTA procedure was associated with a low complication rate, good clinical outcomes, and improved range of motion among patients with anterior shoulder instability and associated glenoid defects.

Diversity, Equity, and Inclusion in Orthopaedic Surgery: Local and National Efforts.

Orthopaedic surgery has not experienced the same increase in diversity as other surgical subspecialties over time. Professional orthopaedic societies across the nation, including the American Academy of Orthopaedic Surgeons, are now making sincere efforts to improve diversity, equity, and inclusion (DEI) within the field. Several national groups provide funding to support DEI -related research as well as scholarships to national meetings. Others are more focused on mentorship and mitigation of residency attrition amongst underrepresented minorities (URMs). Individual residency programs, including the Department of Orthopaedics at Brown University, are engaging in community outreach to attract more diverse candidates to orthopaedics and providing away rotation scholarship support for medical students that identify as female or URMs. These local and national efforts will hopefully lead to a more inclusive environment for all trainees and practitioners within orthopaedics and ultimately improved orthopaedic care for all patients.

A Posterior Acromial Bone Block Augmentation Is Biomechanically Effective at Restoring the Force Required To Translate the Humeral Head Posteriorly in a Cadaveric, Posterior Glenohumeral Instability Model.

PURPOSE: To assess the biomechanical utility of a posterior acromial bone block (PABB) for the treatment of posterior glenohumeral instability. METHODS: Ten fresh-frozen cadaveric specimens were obtained based upon an a priori power analysis. A 2.5-cm scapular spine autograft was harvested from all shoulders. A custom robot device was used to apply a 50-N compressive force to the glenohumeral joint. The humeral head was translated 10 mm posteroinferiorly at 30 degrees from the center of the glenoid at a rate of 1.0 mm/s in 6 consecutive conditions: (1) intact specimen, (2) intact with PABB, (3) posterior capsulolabral tear, (4) addition of the PABB, (5) removal of the PABB and repair of the capsulolabral tear (LR), and (6) addition of the PABB with LR. The maximum force required to obtain this translation was recorded. Paired t tests were performed to compare relevant testing conditions. RESULTS: Ten cadavers with a mean ± SD age of 54.4 ± 13.1 years and mean ± SD glenoid retroversion of 6.5 ± 1.0 degrees were studied. The PABB provided greater resistance force to humeral head translation compared to the instability state (instability, 29.3 ± 15.3 N vs PABB, 47.6 ± 21.0 N; P = .001; 95% confidence interval [CI], -27.6 to -10.0). When comparing PABB to LR, the PABB produced higher resistance force than LR alone (PABB, 47.6 ± 21.0 N; LR, 34.2 ± 20.5 N; P = .012; 95% CI, -23.4 to -4.1). An instability lesion treated with the PABB, with LR (P = .056; 95% CI, -0.30 to 20.4) or without LR (P = .351; 95% CI, -6.8 to 15.7), produced resistance forces similar to the intact specimen. CONCLUSIONS: A PABB is biomechanically effective at restoring the force required to translate the humeral head posteriorly in a cadaveric, posterior glenohumeral instability model. A posterior acromial bone block is a biomechanically feasible option to consider in patients with recurrent posterior instability. CLINICAL RELEVANCE: Augmentation of the posterior acromion may be a biomechanically feasible option to treat posterior shoulder instability.