Abstract
BACKGROUND: The purpose of this systematic review is to compare the outcomes and complications of allograft-prosthetic composite (APC) versus megaprosthesis for shoulder arthroplasty with non-oncologic indications. METHODS: A systematic review was conducted using PubMed, Embase (Ovid), and Cochrane to search for studies through April 2025 that reported outcomes on APC, megaprosthesis, or both with non-oncologic indications. Data was extracted on study details, patient demographics, follow-up durations, surgical indications, outcome measures, range of motion (ROM), surgical complications, and revision rates. RESULTS: Five studies with 157 patients (27 megaprosthesis, 130 APC) met inclusion criteria. Over 25% of the patients were male, and the mean age was 66 years. A majority of patients (n = 155) had undergone prior surgery. Of the four studies that reported ROM, all found improvements post-operatively, which were significant (p < 0.05) for forward flexion (APC and megaprosthesis), abduction (APC), internal rotation (megaprosthesis), and external rotation (megaprosthesis and one of three APC studies). Forty-eight complications and 33 revisions were reported, which both occurred at higher rates following megaprosthesis. CONCLUSION: Compared to APC, megaprosthesis may offer slightly better postoperative ROM but confers a higher risk profile. These findings should be considered when choosing a shoulder arthroplasty technique with non-oncologic indications.