Pyrolytic carbon humeral head in hemi-shoulder arthroplasty: preliminary results at 2-year follow-up

BACKGROUND: In patients with osteoarthritis (OA) and an intact rotator cuff, hemi-shoulder arthroplasty (HSA) can be a viable option as it offers the advantage of keeping the native glenoid intact. However, glenoid erosion has frequently been reported. The aim of this study was to report preliminary clinical results of HSA with a new pyrolytic carbon (pyrocarbon) humeral head. METHODS: This prospective multicenter study included a continuous series of 65 patients who underwent pyrocarbon HSA in 5 centers. RESULTS: At the time of analysis, 1 patient was lost to follow-up, 3 patients underwent revision, and 61 patients were evaluated at a mean follow-up of 25.9 ± 3.3 months. The mean age at index surgery was 57.9 ± 13.3 years. The indications were primary glenohumeral OA in 37 patients, osteonecrosis in 11, secondary OA in 11, and rheumatoid arthritis in 2. The mean Constant score increased from 31.0 ± 15.8 points at baseline to 74.6 ± 17 points at last follow-up. Radiographic analyses showed that 86% of glenoids remained unchanged whereas 14% evolved slightly. CONCLUSIONS: Pyrocarbon HSA grants improvement in pain and function in patients with primary OA or secondary OA after instability but at a lower level in patients with post-traumatic sequelae (secondary OA or osteonecrosis). These preliminary clinical and radiologic results are encouraging, although they need to be confirmed by longer-term follow-up observations.