Radiographic criteria and results of bone graft incorporation in bony increased-offset reverse shoulder arthroplasty: A systematic review

Background Structural bone grafting to address glenoid bone defects in reverse shoulder arthroplasty (RSA) has become increasingly common, allowing restoration of lateralization, tilt, and version. Despite its advantages, graft-related radiographic alterations are frequently reported, while mechanical failure remains relatively uncommon. Interpretation of these findings is limited by the absence of standardized methods for postoperative graft evaluation.Methods This systematic review was conducted according to PRISMA guidelines. PubMed, Scopus, and Google Scholar were searched up to February 8, 2026. Studies evaluating structural glenoid bone grafting in RSA with postoperative radiographic assessment of graft incorporation or failure were included. Two reviewers independently screened studies and extracted data regarding patient characteristics, graft features, imaging modalities, radiographic criteria, and graft-related complications. Methodological quality was assessed using the Newcastle-Ottawa Scale and RoB 2 tool.Results Nineteen studies including 962 shoulders were analyzed. Radiographic assessment was reported at the latest available follow-up, with a mean of 40 months but ranging widely across studies (7 to 152 months). Standard radiographs were the most used imaging modality, followed by CT. Radiographic evaluation criteria were heterogeneous, most frequently based on radiolucent lines, graft thickness changes, or graft lysis. Radiographic signs suggestive of graft resorption were observed in 6.3% of shoulders, whereas graft failure associated with mechanical loosening occurred in 1.9%. Scapular notching was reported in 32.8% of cases.Results Nineteen studies including 962 shoulders were analyzed. Radiographic assessment was reported at the latest available follow-up, with a mean of 40 months but ranging widely across studies (7 to 152 months). Standard radiographs were the most used imaging modality, followed by CT. Radiographic evaluation criteria were heterogeneous, most frequently based on radiolucent lines, graft thickness changes, or graft lysis. Radiographic signs suggestive of graft resorption were observed in 6.3% of shoulders, whereas graft failure associated with mechanical loosening occurred in 1.9%. Scapular notching was reported in 32.8% of cases.Discussion Postoperative graft evaluation remains highly variable across studies, relying predominantly on qualitative radiographic parameters without standardized definitions. Importantly, radiographic signs suggestive of graft resorption were observed in 6.3% of cases, whereas true mechanical failure occurred in only 1.9%, indicating that many radiographic changes may reflect biological remodeling rather than clinically significant compromise.