Cementless surface replacement arthroplasty of the shoulder for osteoarthritis: results of fifty Mark III Copeland prosthesis from an independent center with four-year mean follow-up

Purpose Few studies have reported the outcome of cementless surface replacement (CSRA). We initiated this study to analyze results of the Mark III Copeland prosthesis used as a hemiarthroplasty in patients with glenohumeral osteoarthritis. Materials and methods We retrospectively reviewed 53 consecutive Mark III Copeland CRSA hemiarthroplasties in 46 patients (30 women, 16 men) with glenohumeral osteoarthritis from an independent institution by a single surgeon. Patients were a mean age of 69 years (range, 45-94 years). Mean follow-up was 4.2 years (range, 2-8 years). Fifty uncemented hemiarthroplasties were available for review. Results Mean (range) age-adjusted Constant and Oxford scores improved from 38.5 (15-61) and 22 (9-31) to 75.1 (38-87) and 42 (18-48), respectively. Anterosuperior escape of the humeral head developed in 1 patient who had an oversized humeral component due to progressive rotator cuff failure at 2 years. Moderate glenoid erosion was present in 12% and correlated with oversizing of the humeral component. There was one revision to a stemmed cemented hemiarthroplasty for periprosthetic fracture. No patients have required revision for aseptic loosening, rotator cuff failure, or glenoid erosion to date. Conclusions Copeland surface replacement hemiarthroplasty for glenohumeral osteoarthritis can provide functional results similar to modular stemmed prostheses, with a relatively low revision rate at 4.2 years of follow-up; however, there is high rate of glenoid erosion that may complicate future revision surgery, and we did not achieve the same functional improvement as that achieved from the designer’s institution.