1. Department of Orthopaedic Surgery, Horsens Regional Hospital, Horsens;
2. Orthopaedic Research Unit, Aarhus University Hospital, Aarhus;
3. Department of Orthopaedic Surgery, Randers Regional Hospital, Randers;
4. Department of Orthopaedic Surgery, Aarhus University Hospital, Aarhus;
5. Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark