Abstract
Reverse total shoulder arthroplasty (RSA) with glenoid bone grafting has become a common option for the management of significant glenoid bone loss and deformity associated with glenohumeral osteoarthritis. Despite the increasing utilization of this technique, our understanding of the rates of bone graft union, complications and outcomes are limited. The objectives of this systematic review are to determine 1) the overall rate of bone graft union, 2) the rate of union stratified by graft type and technique, 3) the reoperation and complication rates, and 4) functional outcomes, including range of motion (ROM) and functional outcome scores following RSA with glenoid bone grafting.
A comprehensive search of MEDLINE, Embase, and CINAHL databases was completed for studies reporting outcomes following RSA with glenoid bone grafting. Inclusion criteria included clinical studies with greater than 10 patients, and minimum follow up of one year. Studies were screened independently by two reviewers and quality assessment was performed using the MINORs criteria. Pooled and frequency-weighted means and standard deviations were calculated where applicable.
Overall, 15 studies were included, including nine retrospective case series (level IV), four retrospective cohort studies (level III), one prospective cohort study (level II) and one randomized control trial (level I). The entire cohort consisted of 555 patients with a mean age of 71.9±2.1 years and 70 percent female. The mean follow-up was 33.8±9.4 months. Across all procedures, 84.9% (N=471) were primary arthroplasties, and 15.1% (N=84) were revisions. The overall graft union rate was 89.2%, but was higher at 96.1% among studies that used autograft bone (9 studies, N=308). When stratified by technique, bone graft for the purposes of lateralization resulted in a 100% union rate (4 studies, N=139), while eccentric bone grafts used in asymmetric bone loss resulted in a lower union rate of 84.9% (10 studies, N=345). The overall revision rate was 6.5%, and was lowest following primary cases at 1.8% (11 studies, N=393). The pooled mean scapular notching rate was 20.1% (12 studies, N=497). Excluding notching, the pooled mean complication rate was 21.5% for all cases and 13% for primary cases (11 studies, N=393). When reported, there was significant improvement in post-operative ROM in all planes. There was also improvement in functional outcome scores, whereby the frequency-weighted mean Constant score increased from 25.9 to 67.2 (8 studies, N=319), ASES score increased from 34.7 to 75.2 (4 studies, N=142), and SST score increased from 2.1 to 7.6 (5 studies, N=196) at final follow up.
This review demonstrates that glenoid bone grafting with RSA results in good mid-term clinical and radiographic outcomes. Union rate appears to depend highly on graft type and technique, whereby the highest union rates were seen following the use of autograft bone for the purposes of lateralization. Interestingly, the union rate of autograft bone for the purposes of augmentation in eccentric bone loss is considerably lower and its impact on the long-term survivorship of the implant remains unknown.
