1. Berufsgenossenschaftliche Unfallklinik Frankfurt am Main, Department of Trauma and Orthopaedic Surgery, Frankfurt am Main, Germany
2. Department of Orthopaedic Surgery, Koenig-Ludwig-Haus, Julius-Maximilians-University, Wuerzburg, Germany
3. Supervisory Center North for Public Law Tasks of the Bundeswehr Medical Service, Kronshagen, Germany
4. Orthopaedicum Wiesbaden, Wiesbaden, Germany