Faculty Bibliography

PURPOSE/OBJECTIVE:The purpose of this study was to evaluate the effect that associated glenohumeral dislocations have on outcomes following surgical treatment of proximal humerus fractures. METHODS:This IRB-approved study reports on 301 patients, who underwent operative treatment for proximal humerus fractures at an academic medical center from January 2006 to January 2023. Fractures were classified according to the Neer system. Patients were separated into two cohorts based on whether a glenohumeral dislocation was present at the time of initial injury. Outcomes measured included the Disabilities of the Arm, Shoulder, and Hand (DASH) score, shoulder range of motion (forward elevation, external rotation, internal rotation), readmission rates, complications, hardware removal, and need for revision surgery. Independent samples t-tests and chi-squared analysis were used for continuous and categorical variables, respectively. A binary logistic regression was performed to analyze the influence of these factors on complication rate. RESULTS:230 patients sustained an isolated fracture (PHF) and 71 sustained a fracture-dislocation (FD). Significant differences were observed between the FD and PHF groups in all measured outcomes. The FD group had a poorer DASH score (24.38 ± 19.09 vs 10.54 ± 13.67; P < 0.001) and reduced range of shoulder motion in forward elevation (114° ± 40° vs 162° ± 19°; P < 0.001), external rotation (40° ± 19° vs 66° ± 19°; P < 0.001), and internal rotation (57° ± 26° vs 82° ± 21°; P < 0.001). Readmission rates were higher in the FD group (0.28 ± 0.85 vs 0.05 ± 0.28; P < 0.001). The FD cohort also had a higher rate of complications (25.35% vs 6.52%; P < 0.001), need for removal of hardware (14.08% vs 3.04%; P = 0.002), and overall revision surgery (11.27% vs 1.30%; P < 0.001). The FD cohort demonstrated a greater incidence of AVN (12.68% vs 4.35%; P = 0.012). No significant difference was observed regarding rates of fracture healing and recurrent dislocation. Multivariate analysis in the form of binary logistic regression indicated that fracture-dislocation significantly increased the complication risk (OR = 3.310, 95% CI = 1.42-7.70; P = 0.005). CONCLUSION/CONCLUSIONS:Proximal humerus fracture-dislocations are associated with worse functional outcomes and higher complication rates compared to those without dislocations. These findings highlight the potential need for specialized treatment strategies to mitigate the impact of dislocation on recovery.

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.

BACKGROUND/UNASSIGNED:Few studies have directly compared limitations in activities of daily living (ADLs) between reverse shoulder arthroplasty (RSA) and anatomic total shoulder arthroplasty (aTSA). This study evaluates ADL function at mid-term follow-up in patients with revision-free RSA and aTSA. METHODS/UNASSIGNED:This retrospective cohort study included 250 patients who underwent primary aTSA (n = 177) or RSA (n = 73) with a minimum follow-up of 7 years (mean 10 ± 2 years). Patients who had revision surgery were excluded. Multivariable ordinal logistic regression analysis was used to assess the odds of RSA patients reporting better ADL function compared to aTSA patients. RESULTS/UNASSIGNED:Postoperatively, a greater proportion of aTSA patients reported normal ADLs compared to RSA patients. On multivariable analysis, controlling for baseline differences, RSA patients reported lower ADL function for personal hygiene/toilet needs (Odds ratio [OR] 0.21 [95% CI: 0.07-0.65]; p = 0.006), washing/combing hair (OR 0.36 [0.13-1.02]; p = 0.049), putting on a button-up shirt (OR 0.08 [0.02-0.25]; p < 0.001), and putting on pants (OR 0.12 [0.03-0.39]; p < 0.001). DISCUSSION/UNASSIGNED:After adjusting for differences in baseline factors, RSA patients reported greater difficulty with specific ADL tasks-including toileting, personal hygiene, grooming, and dressing-compared to aTSA patients. LEVEL OF EVIDENCE/UNASSIGNED:Level III; Retrospective cohort study.

BACKGROUND:There has been a trend toward the use of shorter humeral components with the goal of preserving bone, decreasing operative time, and a theoretical decrease in stress shielding. The purpose of this study was to compare the clinical and functional outcomes of anatomic total shoulder arthroplasty among standard-length stem, short-stem, and stemless humeral components, with a minimum of 2-year follow-up. METHODS:A retrospective review of a multicenter international database was performed for anatomic total shoulder arthroplasty with a minimum of 2-year follow-up between 2018 and 2021 using Standard Equinoxe stems, Equinoxe Preserve (Short) stems, or Equinoxe Stemless components (Exactech, Inc., Gainesville, FL, USA). Outcome measures included range of motion and patient-reported outcome measures (PROMs). Postoperative radiographic findings including the presence of glenoid and humeral radiolucent lines in zones specific to the stem design were evaluated. Complication and revision rates were recorded. RESULTS:A total of 825 patients were included (164 standard-length stem, 356 short-stem, and 305 stemless). The mean follow-up was 37.9 ± 12.6 months. There was no significant difference in previous shoulder surgeries or medical comorbidities among the groups. The mean final forward elevation for standard-length stem, short-stem, and stemless components was 156°, 158°, and 156°, respectively (P = .636). Final external rotation for standard-length stem, short-stem, and stemless components was 58°, 57°, and 51°, respectively (P < .001). Final internal rotation scores were similar across groups (P = .090). Final PROMs did not meet the minimal clinically important difference across cohorts. The mean operative time for the standard-length stem group was 101.8 minutes, for the short-stem group 92.7 minutes, and for the stemless group 89.2 minutes (P < .001). There was no statistically significant difference in complication rate or revision rate. The rate of humeral component radiolucent lines was greater for standard-length stems (P < .001) with a rate of 11.9% for standard-length stem, 1.7% for short-stem, and 1.6% for stemless components. Patient satisfaction was also similar among the 3 cohorts (P = .757). CONCLUSIONS:Our findings demonstrate similar postoperative motion and PROM scores irrespective of the humeral stem component used. Complication and revision rates were similar for all 3 cohorts. Radiolucent lines were lowest with the stemless component. Early data support the use of stemless and short-stem humeral components that may be advantageous in decreasing operative time and preserving humeral bone for potential revision. Longer term studies are needed to confirm the survivability and durability of these shorter components.

Parkinson disease (PD) is the second most common neurodegenerative disorder in the United States. Despite its rapid increase in prevalence over recent years, there remains a paucity of literature examining the optimal orthopedic management of populations affected by PD and the risk of complications. In this review, we provide insight into the pathophysiology, etiology, manifestations, and orthopedic management of PD, with an emphasis on adult reconstruction. Although limited outcome studies suggest that joint replacement may consistently offer improvement in pain, there is an increased risk of complications and reoperation, with significant functional improvement often being unpredictable.

The landscape of total shoulder arthroplasty (TSA) is rapidly evolving, with a significant shift toward outpatient procedures. This transition has been supported by enhanced recovery protocols and shorter hospital stays. Key factors for successful outpatient TSA include careful patient selection, focusing on individuals with minimal comorbidities, and preoperative optimization, such as patient education and mental health assessments. Intraoperative considerations like blood loss management, pain control, and surgical efficiency play a crucial role in ensuring positive outcomes. Although challenges remain, including patient selection bias and the need for standardized protocols, ongoing research, innovation in surgical practices, and integration of technology can further enhance the safety and effectiveness of outpatient TSA. Ultimately, with appropriate patient selection and optimization strategies, outpatient TSA can provide comparable outcomes to inpatient procedures, benefiting both patients and health care systems.

BACKGROUND:Pre-osteoarthritic posterior subluxation of the humeral head (PPSHH), also referred to as a Walch B0 glenoid, is characterized by pathologic posterior subluxation of the humeral head without degenerative bony changes on plain radiographs. The purpose of this study was to describe the imaging findings of PPSHH and to assess the relationship between glenoid retroversion and HH subluxation. METHODS:This was a retrospective case series of patients with symptomatic PPSHH. Retroversion was measured on magnetic resonance imaging based on both Friedman's line and the scapular axis line. HH subluxation was measured based on the glenohumeral index (GHI) and the scapulohumeral index (SHI). The relationship between retroversion and HH subluxation was evaluated. The difference in glenoid cartilage thickness between the anterior and posterior aspects of the glenoid was compared. RESULTS:Eight patients were included (mean age, 34.0±4.7 years). Mean retroversion was 17.2°±5.8° based on Friedman's line and 14.0°±5.6° based on scapular axis line. Mean HH subluxation was 63.7%±6.2% based on GHI and 77.5%±9.9% based on SHI. Cartilage thickness was less in the posterior glenoid compared to anterior glenoid, and all patients had selective chondral wear on the posterior glenoid with a posterior labral tear. There was a direct relationship between the degree of glenoid retroversion and HH subluxation. CONCLUSIONS:PPSHH is characterized by posterior glenoid chondral thinning and posterior labral tears in the setting of HH subluxation without erosive osseous changes. This pathology can present with varying degrees of retroversion and HH subluxation, and increasing retroversion is associated with more severe subluxation. Level of evidence: IV.

BACKGROUND:The goal of this study was to utilize preoperative computed-tomography(CT) scans to identify differences in the Hounsfield units(HU) of the acromion in patients who did and did not develop a postoperative acromial and scapular-spine fracture(ASF) after primary reverse total shoulder arthroplasty (rTSA). METHODS:A retrospective analysis was performed at a single institution. All patients undergoing a rTSA with either a 135° neck/shaft angle(NSA) humeral inlay design combined with a lateralized center-of-rotation(COR) glenosphere or a 145° NSA onlay combined with a medialized COR glenosphere design between 2011-2021 with a minimum follow-up of 24-months were included. Demographic characteristics and clinical outcome metric scores were recorded. Preoperative CT scans were analyzed to obtain acromion trabecular bone density measurements in HU in each zone of the scapula based on the Levy classification. Radiographic parameters were evaluated to determine their association with ASF. RESULTS:In total 263-patients were included, 140-patients with a 135° NSA humeral-inlay design;123-patients with a 145° NSA humeral-onlay design. There were no significant differences in baseline demographics between cohorts. The rate of ASF was 6.4%(9/140) for the 135° NSA-inlay-design versus 2.4%(3/123) in the 145° NSA-onlay design. In the non-fracture cohort there was a linear increase in bone density from zone-1(173.9HU)→zone-3(396.5HU)(lateral→medial). In the fracture cohort there was a decrease in bone density from zone-1(282.6HU)→zone-3(154.5HU). Measuring preoperative bone density in all Levy specific fracture-zones resulted in an AUC of 0.96 correlating to excellent predictive value. A threshold cutoff of 99.9 resulted in a sensitivity of 91.6% and specificity of 75.3%. A HU of 99.9 in any of the three-zones resulted in OR 5.1(p<0.0001) for sustaining an ASF postoperatively. A threshold of<50HU was associated with an 8-times higher-likelihood of developing a fracture in that specific zone. Greater than 5° of superior tilt in combination with ≥24mm of distalization was associated with an OR 6.4(p=0.0004) of sustaining an ASF. CONCLUSION/CONCLUSIONS:The current study demonstrates an accurate method of measuring HU at each of the described Levy fracture zones with excellent predictability of patients who are at risk of an ASF following rTSA. Additionally, we found that a HU threshold of <50 HU at any of the three Levy zones was associated with a nearly 8 times higher likelihood of developing a fracture in that specific zone. Lastly, we found that >5° of superior tilt in combination with ≥24mm of distalization was associated with 6.4 times higher likelihood of sustaining an ASF agnostic to prosthesis design.