1. Departement of Surgery; South Karelian Central Hospital; Lappeenranta Finland
2. Department of Orthopedics; Unit of Musculoskeletal Surgery, Tampere University Hospital; Tampere Finland
3. Department of Orthopedics; Karolinska University Hospital, Karolinska Institutet; Stockholm Sweden
4. Department of Orthopedics; University Hospital; Aarhus Denmark
5. Department of Orthopedics; Haukeland University Hospital; Bergen Norway
6. Department of Oncological Surgery; Norwegian Radium Hospital; Oslo Norway
7. Department of Orthopedics; Sahlgren University Hospital; Gothenburg Sweden
8. Department of Orthopedics; University Hospital; Linköping Sweden
9. Coxa Hospital for Joint Replacement; Tampere Finland