1. Department of Orthopaedic Surgery Horsens Regional Hospital Horsens Denmark
2. Orthopaedic Research Unit Aarhus University Hospital Aarhus Denmark
3. Department of Orthopaedic Surgery Aalborg University Hospital Farsø Denmark
4. Department of Orthopaedic Surgery Aarhus University Hospital Aarhus Denmark
5. Department of Biostatistics Aarhus University Aarhus Denmark
6. Department of Clinical Biochemistry Aarhus University Hospital Aarhus Denmark
7. Statens Serum Institute Copenhagen Denmark