Faculty Bibliography

BACKGROUND:Prosthetic joint infection (PJI) after total shoulder arthroplasty (TSA) is a devastating complication. Cephalosporins are considered the standard of care for antibiotic prophylaxis during TSA procedures; however reported β-lactam allergies may result in the use of less effective alternatives which are associated with higher infection and complication rates. The aim of this study is to evaluate the relationship between reported β-lactam allergies, antibiotic choice, and revision rates in TSA. METHODS:A retrospective chart review was conducted on all TSA procedures performed at a single institution between January 2015 and January 2025. Information was collected regarding reported allergies to antibiotics including allergy severity and specific reactions. Additionally, all antibiotics administered during the procedures, intraoperative reactions to administered antibiotics, surgical complications, and subsequent revision procedures were collected. Revision procedures were categorized as septic or aseptic based on preoperative diagnosis. Perioperative antibiotics and patient allergies were categorized into penicillins, cephalosporins, clindamycin, vancomycin and other. RESULTS:Data from 4,232 TSAs were collected. 23% of patients had a reported antibiotic allergy and 15% had a β-lactam allergy. Cephalosporins were administered in 94% of all TSAs, but use declined with increasing β-lactam allergy severity, dropping from 90% in mild cases to 44% in severe cases, with corresponding increases in clindamycin and vancomycin use. Higher allergy severity was strongly associated with reduced cephalosporin use and increased alternative antibiotic use (OR = 0.40, p<.001). Notably, cephalosporins were given to patients labeled as having anaphylactic reactions to penicillins or cephalosporins with no adverse events reported. Overall, intraoperative cephalosporin prophylaxis was significantly associated with decreased all-cause revision odds (OR = 0.47, p<.001) and the presence of a β-lactam allergy was associated with increased likelihood requiring a revision procedure for a presumed septic etiology. CONCLUSIONS:The severity of reported β-lactam allergies strongly influences perioperative antibiotic selection despite evidence that most reported allergies are unreliable, unnecessarily increasing patient risk for PJI. Lack of cephalosporin prophylaxis was associated with increased revision rates, underscoring the clinical and economic value of appropriate antibiotic use. Given the high prevalence of mislabeled β-lactam allergies, established delabeling strategies using allergy testing or test-dosing in the operating room may offer a safe and effective means to increase first-line antibiotic use and improve stewardship. LEVEL OF EVIDENCE/METHODS:Level III, Retrospective Cohort Comparison, Prognosis Study.

BACKGROUND/UNASSIGNED:Advantages of preoperative planning computed tomography (CT) scans for shoulder arthroplasty (SA) are known; however, risks of ionizing radiation exposure remain unknown. We retrospectively reviewed institutional trends in utilization and estimated radiation risk of preoperative planning CT scans obtained for SA. METHODS/UNASSIGNED:From 2016 to 2024, the annual percent incidence of SA patients that received a preoperative planning CT was determined. The National Academy of Sciences Biological Effects of Ionizing Radiation VII report on lifetime attributable risk (LAR) cancer incidences and received radiation dose were utilized to estimate patient-level LAR projections for 100 patients stratified by sex, age, and cancer type. RESULTS/UNASSIGNED: = 0.78) from 53% to 66% of all SA patients. For all solid cancers, LAR (per 100,000 people) decreased as patient age increased, ranging from 73.1 to 9.6 for females and 40.7 to 31.4 for males (from the 50-59-year-old group to the 80-89 group). In the 60-69-year-old and 70-79-year-old groups, estimated thyroid and lung LARs were significantly higher in women. DISCUSSION/UNASSIGNED:Utilization of preoperative shoulder CT scans is increasing. Preoperative shoulder CT may be associated with a small but quantifiable projected cancer risk most pronounced in younger women.

BACKGROUND/UNASSIGNED:This study evaluates outcomes following internal fixation of unstable distal clavicle fractures (DCFs) with or without coracoclavicular (CC) stabilization. METHODS/UNASSIGNED:A retrospective review was conducted for patients who underwent open repair of unstable DCFs at a single institution from 2017 to 2024. Fixation techniques included locking plate alone (P) or plate with CC stabilization [transcoracoid suture button (P + B), coracoid anchor (P + A)]. Collected variables included demographics, clinical details, patient-reported outcome measurement information system (PROMIS) scores, American Shoulder and Elbow Surgeons (ASES) scores, and Visual Analog Scale (VAS) Pain. RESULTS/UNASSIGNED:Seventeen patients with DCFs (17 shoulders;11 males, 6 females; mean age 45 [23-78] years) were followed for an average of 32.0 (3.4-69.3) months. Fixation groups included P (6), P + B (8), and P + A (3). Neer types included IIA (4), IIB (6), and V (7). Mean outcome scores were PROMIS upper extremity 49.2 ± 10.5, pain interference 47.0 ± 7.2, pain intensity 39.3 ± 7.0, ASES 89.3 ± 14.3, and VAS 1.5 ± 2.2. Three patients (18%) experienced postoperative issues: plate prominence (2) and shoulder stiffness (1); none required reoperation. DISCUSSION/UNASSIGNED:The addition of CC stabilization to locking plate fixation in high-risk unstable DCFs results in favorable outcomes and predictable healing rates. LEVEL OF EVIDENCE/UNASSIGNED:IV, case series.

BACKGROUND:The use of large language models (LLMs) is increasingly common. However, LLMs may exhibit sycophancy, echoing users' beliefs while avoiding contradiction. In the present study, we describe sycophancy in general-purpose LLMs when applied to orthopaedic contexts. METHODS:We investigated sycophancy in 2 general-purpose LLMs. We evaluated performance on 3 tasks: (1) accuracy on benchmark answering: LLMs were tested on validated benchmark orthopaedic questions, with correct and incorrect cues, and the change in accuracy and sycophancy error rate were determined; (2) user belief agreement: LLMs were provided with ambiguous statements and a user belief, and LLM agreement, contradiction, and uncertainty were described; and (3) false information detection: false information was placed within a task prompt to measure noncontradiction and propagation rates. RESULTS:Baseline factual accuracy on benchmark questioning was 78%, decreasing with correct hints (71%) (p = 0.49). With incorrect hints, LLM accuracy declined significantly (48%) (p < 0.001), with a sycophancy error rate of 52%. Presented with user beliefs about an indefinite, controversial statement, models echoed user beliefs in 56%, expressed uncertainty in 12%, and contradicted users in 32% of statements. In noncontradiction tasks, models perpetuated incorrect attributions 99% of the time yet reliably corrected statistical distortions 97% of the time. CONCLUSIONS:Although popular general-purpose LLMs have useful orthopaedic applications, they exhibit sycophancy, with a tendency toward agreement and without recognition of ambiguity. This is a key weakness to be addressed. Findings should be interpreted cautiously given the variability in model design, prompting, and models evaluated. CLINICAL RELEVANCE/CONCLUSIONS:The tendency of general-purpose LLMs to agree without recognizing clinical ambiguity may limit their reliability in orthopaedic applications.

BACKGROUND/UNASSIGNED:Elbow contractures can occur due to several causes including age-related degenerative disease, inflammatory conditions, and post-traumatic injury. The resulting pain and reduced range of motion can significantly interfere with activities of daily living and impede patient functionality. One treatment option for elbow contractures is arthroscopic contracture release. The purpose of this study is to evaluate the preoperative risk factors associated with inferior clinical outcomes following arthroscopic elbow contracture release. METHODS/UNASSIGNED:values were adjusted for multiple comparisons using the Bonferroni correction. Postoperative complications, including recurrent contracture, neurological symptoms, and reoperations, were also recorded. RESULTS/UNASSIGNED:= .02) was associated with low postoperative P-UE scores. CONCLUSION/UNASSIGNED:Arthroscopic elbow contracture release can improve function and range of motion; however, outcomes may vary based on preoperative patient characteristics. Female sex may be associated with lower postoperative PROMIS function scores.

BACKGROUND/UNASSIGNED:Three-dimensional (3D) preoperative planning and intraoperative computer-assisted navigation (CAN) may influence baseplate augmentation and screw fixation in reverse total shoulder arthroplasty (RTSA). This study evaluated how these technologies affect augmented baseplate use and screw length. This is a Level IV retrospective study. METHODS/UNASSIGNED:Three hundred primary RTSAs for glenohumeral degenerative conditions (2014-2024) were reviewed. Patients were divided into three groups: (1) 2D-CT planning without CAN (2014-2017, n = 100), (2) early 3D-CT with CAN (2019-2022, n = 100), and (3) recent 3D-CT with CAN (2022-2024, n = 100). Demographics, glenoid morphology, baseplate type, and screw characteristics were compared. RESULTS/UNASSIGNED:Augmented baseplate use was higher in the 3D-CT groups versus 2D-CT (40% and 43% vs. 15%; P < .01) with no demographic or glenoid morphology differences (P > .05). CAN was associated with longer screws when four screws were used (24.6 mm and 25.3 mm vs. 20.8 mm; P < .001) and when comparing the two longest screws (28.5 mm and 27.3 mm vs. 22.9 mm; P < .01). Screw length did not differ between augmented and standard baseplates. DISCUSSION/UNASSIGNED:3D planning and CAN increased augmented baseplate use and screw length. Equivalent screw lengths between augmented and standard baseplates suggest that augmentation does not compromise fixation, supporting its safe use in appropriately selected patients.

» Distal clavicle fractures are less common, accounting for 10% to 30% of all clavicle fractures. » The presence of radiographic nonunion does not correlate with symptomatic nonunion, with a variable percentage of patients necessitating subsequent surgical intervention (20%). » Fracture displacement is associated with a higher risk of nonunion (31%-37%), particularly in Neer type II and V fracture patterns. » Nondisplaced distal clavicle fractures can be treated with nonoperative management (Neer types I, III, and IV). » Surgical treatment is indicated for displaced Neer type II and V fractures. Increased radiographic coracoclavicular (CC) distance in type II and V fractures is an indication for CC stabilization. However, there is no consensus on ideal fixation techniques for fracture fixation and CC stabilization. » Surgical treatment may require secondary implant removal, regardless of the fixation construct used (28%-55%) but especially common with hook plate fixation.

BACKGROUND:Total shoulder arthroplasty (TSA) utilization has increased rapidly following the adoption of the reverse TSA (rTSA). Contemporary forecasts of TSA incidence and prevalence are limited and outdated, particularly in comparison with total hip arthroplasty (THA) and total knee arthroplasty (TKA). We sought to update TSA projections in the United States through 2040 and compare them against THA and TKA. METHODS:We identified adults (≥18 years) who underwent primary TSA, THA, or TKA between 2015 and 2025 in the United States using a large database. Annual incidence (new procedures per 100,000 patients) and prevalence (patients with prior arthroplasty per 100,000) were calculated. For each arthroplasty, linear and Poisson regression models were used to project new cases through 2040, with 95% confidence intervals. COVID year exclusion analysis and segmented analyses were performed using pre and post-COVID years in both linear and Poisson regression models to assess the effect of accelerated post-pandemic rebound. RESULTS:From 2015-2025, we identified 83,203 new TSA, 267,683 new THA, and 354,044 new TKA cases. TSA incidence increased from 13.1 to 45.6 per 100,000 (248.1% change), and prevalence from 41.5 to 222.8 per 100,000 (436.9% change). Across both modeling approaches, new cases for all procedures increased significantly. In Poisson modeling, the greatest proportional annual growth was observed for TSA (12.4% per year), compared with TKA (9.1% per year) and THA (8.5% per year). With linear regression, incidence increased by 2.77 cases per 100,000 per year for TSA, 8.75 for TKA, and 6.26 for THA, with TKA showing the largest additive yearly increase. By 2040, the linear model predicts that shoulder arthroplasty volume will increase by 73.0% to 78.9 cases per 100,000, whereas the Poisson model predicts a 397.4% increase, to 226.8 cases per 100,000. Utilizing post-COVID years, the linear model predicts that TSA volume will increase by 212.9% to 142.7 cases per 100,000, whereas the Poisson model predicts a 2317.8% increase, to 1102.5 cases per 100,000. CONCLUSION/CONCLUSIONS:TSA utilization in the United States has increased significantly over the past decade and is projected to continue rising through 2040. Although TSA remains less common than THA or TKA, it demonstrated the greatest proportional annual growth by Poisson modeling from 2015 to 2025, with much of this acceleration concentrated in the post-COVID period. These updated projections provide essential data for clinicians, health-system leaders, and policymakers as they plan for the growing burden of shoulder arthroplasty.

INTRODUCTION/BACKGROUND:Prosthetic joint infection is a serious complication after primary shoulder arthroplasty, yet no standardized infection prevention protocol exists. This study evaluated current trends in infection prevention among members of the American Shoulder and Elbow Surgeons. METHODS:A 25-item cross-sectional survey was developed to capture commonly used preoperative, intraoperative, and postoperative infection prevention strategies in primary shoulder arthroplasty. The finalized instrument was administered electronically through REDCap to all active American Shoulder and Elbow Surgeons members in November 2024, with 1 reminder sent 2 weeks later. Anonymized responses were categorized by years in practice (<5, 5-10, 10-20, and >20 years). Statistical analyses assessed variability across experience groups. RESULTS:Of 229 responses, 224 were complete and included for analysis. Most surgeons reported using hemoglobin A1c cutoffs (77%), avoiding corticosteroid injections within 3 months of surgery (86%), performing preoperative skin cleansing (78%), using chlorhexidine for preparation (94%), switching scalpel blades (80%) or using electrocautery (79%) after skin incision, and administering perioperative IV antibiotics (76%). Surgeons with <5 years of experience were more likely to use hydrogen peroxide or alcohol-based skin preparation, vancomycin powder, topical skin glue, silver-impregnated dressings, and apply stricter hemoglobin A1c cutoffs, reaching statistical significance in all cases (P < .05). A body mass index cutoff was used by 25% of respondents, with a mean threshold of 42 kg/m2. CONCLUSION/CONCLUSIONS:Substantial variation exists in infection prevention strategies for primary shoulder arthroplasty (SA) across experience levels, highlighting the need for standardized protocols. LEVEL OF EVIDENCE/METHODS:IV, epidemiological study.

The utilization of total shoulder arthroplasty has increased markedly over recent decades, owing to the introduction of reverse shoulder arthroplasty, modular and convertible components, and advances in preoperative planning and intraoperative guidance technology. Three-dimensional (3D) computed tomography (CT)-based planning software enables accurate assessment and correction of glenoid deformity and plan for individualized implant selection and templating. Guidance technology extends this capability into the operating room by allowing the surgeon to replicate the preoperative plan with precision and accuracy. Computer-assisted navigation (CAN) is a guidance technology that provides real-time intraoperative feedback to execute the preoperative plan. CAN is currently available for the glenoid component only and is particularly useful in complex primary and revision cases, providing improved accuracy and precision of glenoid component placement, and better short-term outcomes. Although the cost effectiveness, and long-term benefits on implant survivorship are unknown, CAN represents a safe and effective intraoperative guidance tool while maintaining low complication rates. In this review, we discuss the current status of CAN in shoulder arthroplasty including the surgical technique, and review of literature.