Resurfacing hemiarthroplasty compared to stemmed hemiarthroplasty for glenohumeral osteoarthritis: a randomised clinical trial

Purpose The aim of this study was to conduct a randomised, clinical trial comparing stemmed hemiarthroplasty and resurfacing hemiarthroplasty in the treatment of glenohumeral osteoarthritis. Methods A total of 40 shoulders (35 patients) were randomised to stemmed hemiarthroplasty or resurfacing hemiarthroplasty and evaluated three and 12 months postoperatively using the Constant-Murley score (CMS) and Western Ontario Osteoarthritis of the Shoulder (WOOS) index. Results There were no statistically significant differences in age, gender or pre-operative scores except for WOOS at baseline. Two patients were lost to follow-up. Significant improvements in CMS and WOOS were observed at one year after both arthroplasty designs. At one year, the mean CMS was 48.9 (range 6–80) after resurfacing hemiarthroplasty and 59.1 (range 0–88) after stemmed hemiarthroplasty {mean difference 10.2 [95 % confidence interval (CI) −3.3 to 23.6], P = 0.14}. The mean WOOS was 59.2 (range 5.2–100.0) and 79.4 (range 12.8–98.6), respectively [mean difference 20.2 (95 % CI 3.4–36.9), P = 0.02]. No major complications occurred and there were no revisions. Conclusions The effects of resurfacing hemiarthroplasty tended to be inferior to those of stemmed hemiarthroplasty. It is unclear whether this reflects a real difference in effect or baseline differences due to the limited number of randomised patients. We suggest there is a need for a larger, more definitive trial.