Results of Glenoid Bone Grafting Techniques in Reverse Shoulder Arthroplasty

Introduction: Secure fixation of the glenoid component in reverse shoulder arthroplasty (rTSA) with glenoid bone deficiency may be a challenge.

Purpose: This study aims to present the clinical and radiological results of bone grafting glenoid defects in reverse shoulder arthroplasty (rTSA)

Methods: Demographics, radiographs, and surgery data were prospectively collected and analysed. At the final follow up range of motion, subjective shoulder value (SSV) and the Constant Score were recorded. Radiographic analysis was performed in every follow-up.

Results: Between 2005 and 2017, 34 patients had glenoid bone grafting during RSA. 29 female and 7 male. Average age was 72 years (range 46 – 88). Indications were: cuff tear arthropathy 8; revision of failed other prosthesis 20; primary osteoarthritis 4; rheumatoid arthritis 3l; second stage revision for infection 1. The glenoid defect was contained in 24 patients and therefore impaction graft with a combination of bone graft substitute and / or humeral head allograft or autograft was performed. In 12 patients the glenoid defect was severe and uncontainable and therefore a graft-implant composite glenoid was implanted using humeral head autograft or allograft. Average follow up was 3.6 years (range 1 – 10). Mean Constant score improved from 34 before surgery to 63 after surgery. Mean SSV score improved from 0.9 to 8.3. Active movements improved significantly with forward elevation increased from 54^o to 123^o; abduction from 48^o to 123^o; external rotation from 24^o to 38^o; internal rotation from 57^o to 70^o. Radiographs at final follow up showed no lucencies around the glenoid component and no evidence of loosening. In 2 cases there was a grade I notching.

Conclusion: Impaction grafting of the glenoid or graft-implant composite insertion when needed results in good clinical and radiological outcomes.