A Comparison Between a Pyrocarbon and a CoCr Shoulder Resurfacing Implant

Inclusion Criteria: * Primary or secondary osteoarthritis of the shoulder * Age 40-75 years * Patient capable of giving informed consent * Patient agrees to comply with the study plan Exclusion Criteria: * Destruction of the proximal humerus * Insufficient bone stock * Deficient rotator cuff or earlier failed surgery of the rotator cuff * Large muscle defects or insufficient blood supply in the affected arm * Neuromuscular disorders * Infection, untreated malignancy or transmittable disease preventing the patient from fulfilling the study * Patient unwilling to comply with study regulations * Patient with earlier allergic reaction to pyrocarbon * Patient with known metastatic disease * Patient who has been treated with more than 10 mg corticosteroids (e.g. Prednisone) daily within 3 months from surgery. * Patient participating in other clinical study * Patient in need of glenoid replacement