1. Department of Knee Surgery N 17, Russian Research Institute of Traumatology and Orthopaedics n.a. R.R. Vreden, Saint Petersburg 195427, Russia
2. Department of Surgery, Lovisenberg Diakonale Hospital, 0440 Oslo, Norway
3. Department of Nursing Science, Institute of Health and Society, Faculty of Medicine, University of Oslo, 0318 Oslo, Norway
4. Department of Family Health Care Nursing, University of California, San Francisco, CA 94143-0606, USA
5. Department of Research and Development, Lovisenberg Diakonale Hospital, 0440 Oslo, Norway
6. Department of Knee Surgery N 10, Russian Research Institute of Traumatology and Orthopaedics n.a. R.R. Vreden, Saint Petersburg 195427, Russia
7. Department of Research and Development, Division of Emergencies and Critical Care, Oslo University Hospital, 0424 Oslo, Norway
8. Institute of Clinical Medicine, University of Oslo, 0316 Oslo, Norway