1. Haugesund Hospital, Karmsundgt
120, Haugesund, 5521, Norway.
2. The Norwegian Arthroplasty Register, Department
of Orthopaedic Surgery, Haukeland University
Hospital, 5021 Bergen, Norway.
3. Lovisenberg Diakonale Hospital, Lovisenberggata
17, N-0440 Oslo, Norway.
4. Department of Radiology, Haukeland University
Hospital, 5021 Bergen, Norway.
5. Department of Clinical Medicine, Faculty
of Medicine and Dentistry, University of Bergen, 5021
Bergen, Norway.