Abstract
Background
The Copeland shoulder resurfacing arthroplasty (CSRA) (Figure1) is a cementless, pegged humeral head surface replacement which has been in clinical use since 1986. The indications for CSRA are more or less the same as conventional stemmed arthroplasty. This procedure can be considered for all patients who require shoulder replacement due to GHJ arthritis resulted from primary or secondary OA, RA, and other variations of inflammatory arthritis. It is also suggested as the first choice option for relatively young patients with post-traumatic arthritis, avascular necrosis (AVN), and instability arthropathy. This observational study reports functional and radiological outcome in CSRA during 4 years follow-up.
Methods
109 consecutive patients with primary osteoarthritis (45.9%), rheumatoid arthritis (39.4%), rotator cuff arthropathy (9.2%), and avascular necrosis (5.5%) underwent CSRA. Patients including 68 females (63%) and 41 males (37%) underwent this procedure (63 right-sided and 46 left-sided including 9 bilateral shoulders). The outcome assessment included pain and satisfaction, Oxford Shoulder Score (OSS), Constant Score (CS), and SF-12. Imaging was reviewed for glenoid morphology (Walch classification) (Figure2) and humeral head migration. The average follow-up period was 4 years, (range: 1 to 10 years).
Results
Primary OA and RA were the most common underlying pathologies in 45.9% and 39.4% of patients, respectively, followed by RCA (9.2%) and AVN (5.5%). Approximately 89% of arthroplasties were primary and 11% were revisions. Other body joints were affected in 85% of patients and nearly 70% of them had accompanying health conditions and co-morbidities (e.g. heart diseases, hypertension, and diabetes mellitus).
A strong correlation found for OSS regarding CS and physical SF-12 subscale. Pain and physical limitation had negative correlation with satisfaction and shoulder-specific tools. Walch type A (68%) and superior HH migration (16.8%) were the commonest radiographic presentations. There was high correlation between migration and physical limitation, pain, satisfaction, OSS, and CS. A significant difference noted for OSS, CS, physical limitation, pain and satisfaction between migration and non-migration groups.
Discussion
The CSRA provides pain relief and a good functional outcome in many patients. The main disadvantage is the technical difficult of implanting a glenoid which many surgeons now perceive as being essential in order to gain early pain relief and a better functional outcome. Our results show a predictable relationship between outcome and pathology, with osteoarthritic patients having the most favourable outcome.
Glenoid wear and cuff related problems are the major reasons for failure. Improvements in the design and surgical technique to reduce the likelihood of HH migration remain the major challenge. CSRA should be considered the implant of choice in younger patients with osteoarthritis and RA where there is concern over conserving bone stock for future revision. Considering the nature of underlying pathologies it is appropriate to use a combination of generic and shoulder-specific outcome tools.
