1. Department of Surgical Sciences, Orthopaedics, Uppsala University, Uppsala, Sweden
2. Uppsala Clinical Research Center, Uppsala, Sweden
3. Department of Diagnostics and Intervention (Orthopaedics), Umeå University, Umeå, Sweden
4. Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
5. Department of Orthopaedics, Lund University, Skåne University Hospital, Malmö, Sweden