1. Department of Orthopaedic Surgery , Aarhus University Hospital , Aarhus , Denmark
2. Department of Clinical Medicine , Aarhus University Hospital , Aarhus , Denmark
3. Department of Biochemistry and Immunology , Lillebaelt Hospital , Vejle , Denmark
4. Department of Gynaecology and Obstetrics , Odense University Hospital and Department of Clinical Medicine, University of Southern Denmark , Odense , Denmark