Clinical outcomes of augmented rTSA glenoid baseplates

Abstract

BackgroundGlenoid wear is a common challenge in patients undergoing reverse total shoulder arthroplasty (rTSA). Augmented baseplates have recently been designed to address this. The purpose of this study is to determine the clinical outcomes, complications, and revision rates of patients undergoing rTSA with an augmented baseplate compared to those that received a standard, non-augmented baseplate. MethodsPreoperative and postoperative data were analyzed for 414 patients with glenoid bone loss who underwent primary rTSA with either an 8° posterior augmented glenoid baseplate, a 10° superior augmented baseplate (SAB), or an 8° posterior/10° superior augmented baseplate (P/SAB). These patients were compared to 1547 primary rTSA patients who received a standard baseplate. Clinical outcomes were scored using the Simple Shoulder Test (SST), UCLA, ASES, Constant and SPADI clinical outcome scoring metrics. Range of motion for active abduction, forward flexion, internal rotation and external rotation were used to quantify function. Complication and revision rates were also documented, and postoperative radiographs were analyzed for scapular notching. A two-tailed, unpaired t-test was used to identify differences between continuous parameters and a Chi Square test was used for categorical parameters, with P < .05 denoting a significant difference. ResultsAt an average follow-up of 47.1 ± 23.1 months, the augmented baseplates performed as well, or better, than standard baseplates, with a similar complication rate, revision rate, aseptic glenoid loosening rate, and scapular notching rate. DiscussionAugmented baseplates are a safe and effective option for patients with glenoid bone loss in the setting of rTSA at mid-term follow-up. For each baseplate type, the outcomes were similar, and the complication/revision and scapular notching rates were low and comparable to that of the standard baseplate cohort. Level of evidenceLevel III, retrospective comparative study.