Background: Successful total shoulder arthroplasty (TSA) relies on accurate placement of implants, which is difficult in the setting of bone loss or deformity. Technologies are becoming available to provide intraoperative assistance to better execute the preoperative plan. The purpose of this study was to compare patient outcomes following TSA utilizing either computer navigation or conventional techniques. Methods: This retrospective review included 180 Primary Exactech TSA cases with a minimum 2-year follow-up. There were 40 anatomic (12 non-navigated, 28 navigated) and 140 reverse (80 non-navigated; 60 navigated) TSA procedures. Patient groups were similar in age, sex, side involved, and prior surgery. Patient-reported outcome measures, complications, revisions, and reoperations were assessed and compared between non-navigated and conventional groups. Results: Of available patients, the navigated anatomic cohort had statistically significant improvements compared to the non-navigated cohort in American Shoulder and Elbow Surgeons (ASES), Oxford, and pain scores. For the navigated reverse cohort, significant improvements were seen in Oxford score. In multivariate analysis, all outcomes favored the navigated cohorts, with ASES, Oxford, and patient function scores reaching statistical significance. Complications occurred more frequently in the non-navigated reverse cohort. Revisions and/or reoperations were more frequent in non-navigated shoulders. Conclusions The use of computer navigation in TSA may be associated with decreased complication rates and improved patient outcomes, a benefit to surgeons and their patients. However, the lack of radiographic assessment is a limitation, and as with all new technology, further research with longer follow-up is needed to fully define the role of navigation in TSA. Level of evidence: III.

This systematic review and meta-analysis aimed to assess the efficacy of prolotherapy compared to control or placebo-based treatments. Methods: A comprehensive search of PubMed, Ovid, and Scopus was conducted up to April 2025. Inclusion criteria encompassed clinical studies comparing prolotherapy with control or placebo treatments and evaluating outcomes such as pain, function, and range of motion. Results: Eight studies involving 431 participants met the inclusion criteria. Patient-reported outcomes, including pain visual analog scale and Shoulder Pain and Disability Index, showed no statistically significant differences between prolotherapy and controls. Prolotherapy demonstrated a small but statistically significant improvement in shoulder abduction (mean difference, 7.08°; 95% CI, 2.49°–11.66°). Other range of motion measures, such as forward flexion, internal rotation, and external rotation, showed no significant differences. Radiographic outcomes, including tendon thickness and elasticity, suggested potential structural benefits but did not consistently translate to clinical improvements. Conclusions: Prolotherapy is not superior to control treatments for rotator cuff tendinopathy. While it offers minor gains in shoulder abduction, its clinical benefits are limited. Level of evidence: III.

Frozen shoulder (FS) is a challenging disorder defined by persistent shoulder pain and progressively reduced joint motion. Despite its clinical significance, the underlying pathophysiology remains incompletely understood, posing challenges to optimal management. This review examines current treatment strategies, encompassing conservative approaches as well as procedural options. Evidence comparing the outcomes, complications, and recovery profiles of these techniques is critically analyzed to guide decision-making based on patient-specific factors and disease stage. Furthermore, recent advancements in understanding the molecular mechanisms of FS and the potential for novel therapeutic approaches are discussed. This comprehensive review underscores the importance of tailored treatment strategies and calls for further high-quality research to address persistent knowledge gaps in managing FS.

Acromioplasty is frequently performed during arthroscopic rotator cuff repair (ARCR) to address subacromial impingement, though its clinical value remains debated. This meta-analysis examines whether acromioplasty improves functional outcomes, pain relief, or re-tear rates in patients undergoing ARCR for full-thickness rotator cuff tears. Methods: A systematic search of PubMed, Embase, Cochrane Library, and Scopus was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify randomized controlled trials (RCTs) from 2011 to 2023. Six RCTs comparing ARCR with and without acromioplasty were included. Primary outcomes included functional scores of American Shoulder and Elbow Surgeons (ASES), Western Ontario Rotator Cuff Index, University of California, Los Angeles scores, pain levels (visual analog scale [VAS]), and re-tear rates. Data were pooled using a random-effects model. Certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE). Results: Across 574 patients, both groups demonstrated improvement in functional outcomes. The acromioplasty group showed a modest advantage (e.g., ASES score: mean difference, 2.93), but these gains did not exceed the minimal clinically important difference. There were no significant differences in pain relief (as measured by VAS) or re-tear rates between groups. The risk of bias was moderate in some trials due to a lack of blinding. GRADE assessment rated evidence as high for ASES scores and moderate for other outcomes. Conclusions: Acromioplasty offers statistically modest improvements in shoulder function but does not meaningfully enhance pain relief or reduce re-tear rates. Given these findings, the routine use of acromioplasty in ARCR is not supported; however, select patients may benefit based on individual anatomical or clinical factors. Level of evidence: I.

Acellular dermal matrix (ADM) patch augmentation in rotator cuff repair reinforces the repaired tendon and provides additional structural support. This study aimed to compare outcomes based on rotator cuff tear size. Methods: We retrospectively reviewed patients who underwent ADM-augmented rotator cuff repair at two hospitals between April 2021 and April 2023. After excluding subjects with <2 years of follow-up or no magnetic resonance imaging (MRI) at 6 months, patients were grouped based on tear size: ≤30 mm (group 1) and >30 mm (group 2). Outcomes were American Shoulder and Elbow Surgeons score, Constant-Murley score, University of California, Los Angeles score, pain visual analog scale score, and range of motion (ROM). Retear was defined based on Sugaya type 4–5 on 6-month MRI. Results: Both groups showed significant improvement in postoperative clinical outcomes compared with preoperative outcomes, with no significant intergroup differences. ROM gains were limited overall, with significant increases only in group 1 for forward flexion and scaption. Stiffness occurred in 4.8% of group 1 and 17.9% of group 2 patients. Retear was found in 1 of 21 patients (4.8%) in group 1 and 7 of 28 (25.0%) in group 2. Conclusions: Arthroscopic rotator cuff repair with ADM patch augmentation showed reduced retear rates and improved clinical outcomes across tear sizes. Postoperative ROM improvements were limited, and stiffness tended to occur more frequently in larger tears. Thus, the success of ADM patch augmentation depends on patient selection and appropriate graft application. Level of evidence: III.

Little is known about the potential negative or positive effects of peritendinous infiltration with corticosteroids in the non-surgical treatment of partial distal biceps tendon tears. Peritendinous fluid, synovitis, and bursitis often accompany partial tears and can be a source of persistent pain. We hypothesize that peritendinous corticosteroid infiltration is a safe non-surgical treatment option for complaints related to a partial distal biceps tendon rupture. Methods: A single-center retrospective analysis was performed on a cohort of 52 patients with partial distal biceps tears (<50% of the footprint involved), as confirmed by magnetic resonance imaging. All patients received an ultrasound-guided intrabursal peritendinous infiltration with 1 mL of triamcinolone acetonide (10 mg/mL) and 4 mL of 2% lidocaine HCl. Patient files were reviewed for demographic information, date of injury, injury mechanism, treatment modality (operative or nonoperative), clinical follow-up (2011–2021), and complications, including progression to a complete rupture. Results: The median duration of follow-up after infiltration was 15 months (1.2–45 months). No infiltration-related complications were observed following infiltration therapy. Surgical reconstruction was ultimately performed in 65% of the patients with a partial tear. One patient sustained a trauma to the elbow in the weeks following infiltration, resulting in a complete tear. Conclusions: Infiltration with corticosteroids is a safe treatment option for patients with a partial tear of the distal biceps who failed progressive exercise therapy. Surgical reconstruction was avoided in 35% of patients following infiltration treatment. Level of evidence: IV.

Humeral head avascular necrosis (AVN) can cause significant shoulder morbidity and represents the second most common site of nontraumatic osteonecrosis after the femoral head. The pathophysiology centers on disrupted blood supply, ultimately leading to bone death and structural compromise. It is associated with various etiologies, including trauma, iatrogenic factors, hematologic conditions, lifestyle factors, certain environmental exposures, and systemic diseases. Diagnosis relies on a combination of clinical assessment and radiographic evaluation, with magnetic resonance imaging serving as the most sensitive modality for early detection. The Cruess classification system guides treatment decisions. Although conservative measures are used in early stages, they carry a risk of progression, as they do not alter the disease course—unlike surgical techniques such as core decompression. Arthroplasty is reserved for later stages with evidence of collapse, with research suggesting that the use of pyrocarbon in hemiarthroplasty may help reduce glenoid erosion. This review provides a comprehensive overview of humeral head osteonecrosis, emphasizing its etiology, clinical evaluation, imaging findings, and treatment strategies. It highlights the growing support for early operative intervention over conservative management, emerging treatment modalities such as biologic augmentation and allografting, and promising new materials like pyrocarbon in hemiarthroplasty to mitigate glenoid erosion.

A cadaveric biomechanical study was used to analyze arm positions that could lead to increased risk of subscapularis tears due to subcoracoid impingement. Methods: Six cadaveric shoulders (two male and four female; mean age, 68.4±2.3 years) were evaluated for subcoracoid external impingement using a custom shoulder testing system with a pressure-mapping sensor. The contact area and the mean and peak contact pressures between the subcoracoid arch and the subscapularis complex were measured. Eight arm positions were assessed, including 20° and 60° forward flexion (FF) and abduction (ABD) with maximal internal rotation (IR) and external rotation (ER). Results: The overall incidence of subcoracoid impingement was 52.1% across all tests, with no contact observed at 20° ABD in the maximal IR position. Except for 20° ABD with maximal IR, the mean contact area significantly differed across the seven arm positions (P=0.009). However, mean and peak contact pressures did not show significant differences (P=0.188 and P=0.065, respectively). The highest mean contact pressure was recorded at 60° ABD with maximal ER (25.7±17.4 kPa), followed by 20° FF with maximal IR (23.2±12.5 kPa), 60° FF with maximal IR (18.2±8.3 kPa), and 60° ABD with maximal IR (18.3±12.0 kPa). The contact area and peak contact pressure exhibited similar trends to mean contact pressure. Conclusions: This cadaveric study demonstrated increased subcoracoid arch contact when shoulders were at 20° and 60° FF with IR and at 60° ABD with both ER and IR. These findings suggest potential external subscapularis impingement in these positions, although not all comparisons were statistically significant. Level of evidence: Cadaveric biomechanical study

The role of manipulation under anesthesia (MUA) without arthroscopic capsular release in patients with preoperative stiffness undergoing arthroscopic rotator cuff repair (ARCR) remains unclear. Additionally, the association between shoulder stiffness and tendon healing after ARCR is still controversial. This study aimed to compare the clinical outcomes and retear rates between patients with preoperative stiffness treated by MUA alone and those without stiffness. Methods: This retrospective study included 322 patients who underwent ARCR for full-thickness tears between January 2012 and May 2022 with a minimum 2 years of follow-up. Clinical outcomes—including passive range of motion (ROM); the Japanese Orthopedic Association (JOA) score; and the University of California, Los Angeles (UCLA) score—were assessed preoperatively and at 3, 6, 12, and 24 months postoperatively. Patients were divided into the stiffness group (MUA completed) and the non-stiffness group. Retears were evaluated using magnetic resonance imaging at 6 months postoperatively, and retear rates were analyzed by tear size (medium vs. large/massive). Results: Eighty-eight patients with stiffness and 234 without stiffness met the study inclusion criteria. Preoperative ROM, JOA, and UCLA scores were significantly lower in the stiffness group. Both groups showed significant improvements at final follow-up, with greater gains in the stiffness group. Final outcomes were comparable, except for external rotation. In medium-sized tears, the retear rate was significantly lower in the stiffness group (1.9%) than in the non-stiffness group (10.8%) (P=0.042). No significant difference was observed for large/massive tears. Conclusions: Patients with preoperative stiffness treated with MUA alone achieved comparable outcomes to those without stiffness, with improved tendon healing in medium-sized tears. Level of evidence: III

This systematic review evaluates the clinical outcomes of two distinct, arthroscopic techniques for the surgical repair of massive rotator cuff tears; lower trapezius tendon (LTT) transfer and muscle advancement (MA). Methods: Eleven studies, involving 433 patients, selected based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, were analyzed. Results: MA significantly improves functional outcomes, demonstrated by higher Constant-Murley scores (mean difference: 26.26 vs. 18.31, P<0.001), University of California, Los Angeles shoulder scores (14.95 vs. 8.3, P<0.001), acromiohumeral distance (AHD; 1.94 mm vs. 0.40 mm, P<0.001), and greater abduction recovery (46.48° vs. 31.86°, P=0.030). However, visual analog scale score was better reduced in the LTT transfer groups (–3.69 vs. –2.33, P<0.001), with greater external rotation improvement (25.67° vs. 7.74°, P<0.001) and lower retear rates (11.89% vs. 19.42%, P=0.031). The complication profiles differed between techniques: LTT transfer carried a higher risk of graft rupture (2.64% vs. 0%, P=0.031), while arthroscopic MA was associated with increased postoperative stiffness (2.91% vs. 0%, P=0.011). Conclusions: Arthroscopic MA is recommended for younger, active patients with mobile residual tissue to optimize abduction and AHD restoration. In contrast, LTT transfer is better suited for cases involving massive defects requiring dynamic stabilization and external rotation recovery. These findings emphasize the importance of individualized surgical planning that considers tear severity, tissue viability, and patient functional demands. Despite limitations stemming from retrospective study designs and clinical heterogeneity, this review highlights the distinct clinical advantages and appropriate indications for both techniques.