Early Improvements in Motion and Pain Using the Zimmer Biomet Comprehensive Glenoid Vault Reconstruction System for Severe Bone Loss in Reverse Shoulder Arthroplasty

INTRODUCTION Custom glenoid baseplates have been introduced to address severe glenoid bone loss in the setting of shoulder arthroplasty. The purpose of this study is to evaluate and report clinical outcomes, radiographic assessment of baseplate fixation, and post-operative complications in patients treated with a reverse total shoulder arthroplasty (rTSA) and the custom Zimmer Biomet Comprehensive Glenoid Vault Reconstruction System (VRS) in the setting of severe glenoid bone loss. MATERIALS AND METHODS Patients who underwent rTSA (primary or revision) using the Zimmer Biomet Comprehensive Glenoid VRS from 2016 to 2025 were identified. Data collection included patient demographics, clinical outcomes, and complications. Exclusion criteria included any patients who did not complete follow up after surgery. RESULTS Eighteen patients (61.1% females) had a mean age of 71.4 years at surgery. Mean follow up time was 27.4 months. Fourteen (77.8%) patients had prior arthroplasty and four (22.2%) patients underwent primary arthroplasty. The durations from CT scan and office visit to surgery were 4.9 months and 3.9 months, respectively. From pre-operatively to one-year post-operatively, forward flexion improved from 45˚ to 128˚ (p<0.01), external rotation at the side improved from 7˚ to 35˚ (p<0.01), and external rotation in abduction improved from 26˚ to 84˚ (p=0.04). The PROMIS pain score improved from 66 to 53 (p<0.05), while the depression and upper extremity function scores did not improve. There were four complications requiring revision surgery (22.2%), including three dislocations and one baseplate failure. CONCLUSION Reverse total shoulder arthroplasty with the VRS custom glenoid baseplate can improve early ROM and pain in patients with severe, uncontained glenoid bone defects. Despite the severity of the pathology, complications specific to the custom baseplate are low, while the overall surgical complications and rates of subsequent revision surgery are moderate.