1. From the Center of Rheumatic Diseases, Department of Internal Medicine and Department of Orthopaedics and Physiatrics, Tampere University Hospital, Tampere, Finland, and Medical School University of Tampere, Finland, Institute of Biomaterials, Tampere University of Technology, Tampere, Finland and Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland and Coxa, Hospital for Joint Replacement, Tampere, Finland