Comparison of Stemless and Stemmed Shoulder Arthroplasty for Osteoarthritis

This is a randomized controlled trial comparing the Comprehensive Nano stemless total shoulder arthroplasty (intervention group) with the Comprehensive un-cemented stemmed total shoulder arthroplasty (control group). All Danish citizens with glenohumeral osteoarthritis indicating a total shoulder arthroplasty referred to the orthopedic department at Copenhagen University Hospital in Gentofte will be offered participation in the trial. The following exclude from participation in the study: below 18 years of age; cognitive or linguistic impairment; insufficient function of the rotator cuff; poor bone quality and ASA group 4-5. A total of 122 patients will be included of which 56 will be part of radiostereometric analysis (RSA) study of humeral component migration. This will allow a maximum of 20% drop out. The primary outcome is magnitude and pattern of migration of the humeral component assessed by RSA. The secondary outcomes are patient-reported outcomes, functional outcome, readmission, complications, revisions, changes in bone mineral density (BMD) of the proximal humerus assessed by duel energy x-ray absorptiometry (DXA) and economy (cost utility analysis). To avoid bias in some of these outcomes, the patient will not know what type of humeral component was used. The patients are examined before the operation and 3, 6, 12 and 24 months after the operation.