1. Department of Orthopedics, Koenig-Ludwig-Haus, University of Wuerzburg, Wuerzburg, Germany
2. Department of Orthopedic Surgery, Diakonissen Hospital, Schladming, Austria
3. OCW, Wuerzburg, Germany
4. Department of Orthopedic Surgery, Pius-Hospital, Carl-von-Ossietzky-University, Oldenburg, Germany
5. Orthopedic Center for Musculoskeletal Research, University of Wuerzburg, Wuerzburg, Germany