Functional Outcomes of Patients With Proximal Humerus Fractures Treated With Primary Versus Salvage Reverse Shoulder Arthroplasty: A Cohort Study of 41 Patients

Introduction Reverse shoulder arthroplasty (RSA) is an option for patients with complex fractures of the proximal humerus and a salvage option for osteosynthesis failure, fracture sequelae, and hemiarthroplasty (HA) revision. The objective of this study was to compare the functional outcomes of primary RSA for proximal humerus fractures (PHFs) with those of salvage RSA for the failed treatment of PHFs. We hypothesized that patients undergoing primary RSA would experience significantly less pain and better functional outcomes than those receiving RSA as a salvage procedure. Methods This was a retrospective cohort study of patients with PHFs who underwent RSA initially or as a salvage procedure due to failure of conservative treatment, osteosynthesis, or HA. The demographic characteristics of the patients and the radiological features of the initial fracture were considered. Functional outcomes were assessed in terms of range of motion (ROM), the Constant-Murley score (CMS), the subjective shoulder value (SSV), and pain (visual analog scale (VAS)). For the comparative statistical analysis, the t-test and Mann-Whitney U test were used. Results Ninety patients underwent RSA, but only 41 patients were included. There were 23 patients in the primary RSA group and 18 in the salvage RSA group, with an average follow-up of 15 months (12-80 months). The primary RSA group experienced significantly less pain (VAS: 0.5±0.13 vs. 1.8±0.40) (p=0.002) and had a better CMS functional index score (73.2±1.6 vs. 65±3.01) (p=0.01) at the end of the follow-up period. No differences in ROM (active anterior elevation and external or internal rotation) or SSV were observed between the two groups. Conclusions In this series of patients, ROM was similar among the patients who underwent primary RSA and those who underwent salvage RSA; however, those who underwent primary RSA had better but not clinically relevant CMS and significantly less pain.