Glenoid structural bone grafting in reverse total shoulder arthroplasty: clinical and radiographic outcomes

Abstract

Background: Current options for reconstruction of large glenoid defects in reverse total shoulder arthroplasty (RTSA) include structural bone grafting, use of augmented components, or 3D-printed custom implants. Given the paucity in the literature on structural bone grafts in RTSA, this study reflects our experience on clinical and radiographic outcomes of structural bone grafts used for glenoid defects in RTSA.

Methods: We identified 33 consecutive patients who underwent RTSA using structural bone grafts for glenoid bone loss between 2008 and 2019. Twenty-six patients with a mean clinical follow-up of 4.4 ± 3.9 years and a mean radiographic follow-up of 2.7 ± 3.2 years were included. Patient demographic data, perioperative functional outcomes, radiographic outcomes, complications, and reoperation rates were determined.

Results: Between 2008 and 2019, 26 RTSAs were performed using structural autograft or allograft for glenoid defects. There were 20 females (77%) and 6 males (23%), with a mean presenting age of 68 years (range 41-86), mean BMI of 29 (range 21-44), and mean Charlson Comorbidity Index of 3 (range 0-8). There were 19 cases of central glenoid defects, and 7 were combined central and peripheral defects. Structural grafts included humeral head autograft (7), proximal humerus autograft (7), iliac crest autograft (7), distal clavicle autograft (2), and femoral head allograft (3). All 18 revision RTSA cases had simultaneous humeral-sided revision. There was significant postoperative improvement in American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form scores (27.0 ± 12.6 preoperation vs. 59.8 ± 24.1 postoperation; P < .001) and visual analog scale scores (8.1 ± 3.6 preoperation vs. 3.0 ± 3.2 postoperation; P < .001). Range of motion improved significantly for active forward elevation (63° ± 36° preoperation vs. 104° ± 36° postoperation; P < .001) and external rotation (21° ± 20° preoperation vs. 32° ± 23° postoperation, P = .036). Eighty-eight percent of cases (23 of 26) had successful reconstruction of the glenoid, defined as no visible radiolucent lines nor glenoid component migration at final follow-up. The reoperation rate was 19% (5 of 26). Postoperative complications included 2 cases of acromial stress fractures that were treated nonoperatively, for a total complication rate (including reoperation) of 27% (7 of 26 cases).

Conclusions: The use of structural bone autografts and allografts in RTSA was associated with improved outcome scores and range of motion. A reoperation rate of 19% and total complication rate of 27% were reported for these challenging cases. However, 86% of these complications were not related to structural glenoid reconstruction failure. Structural grafts are a reasonable option for glenoid reconstruction in RTSA cases with glenoid bone loss.

Keywords: Reverse total shoulder; glenoid defect; glenoid graft; primary shoulder arthroplasty; revision shoulder arthroplasty; shoulder.