1. Department of Biomedicine, Aarhus University, Aarhus, Denmark;
2. Department of Rheumatology, Aarhus University Hospital, Aarhus, Denmark;
3. King Christian 10th Hospital for Rheumatic Diseases, Gråsten and Hospital of Southern Jutland, Jutland, Denmark;
4. Institute of Regional Health Research, University of Southern Denmark, Odense, Denmark;
5. Spine Centre of Southern Denmark, Hospital Lillebaelt Middelfart, Middelfart, Denmark;
6. Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark;
7. Department of Radiology, Hospital Lillebaelt, Vejle, Denmark;
8. Department of Radiology, Aarhus University Hospital, Aarhus, Denmark;
9. Diagnostic Center, Silkeborg Regional Hospital, Silkeborg, Denmark;
10. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark;
11. Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark