1. BG Klinik Tübingen, Department of Traumatology and Reconstructive Surgery, Eberhard Karls University of Tübingen, Tübingen, Germany
2. Department of Orthopaedics and Trauma Surgery, Klinik Gut, St. Moritz, Switzerland
3. Schön Klinik Neustadt, Neustadt in Holstein, Germany
4. Department of Orthopaedic Surgery, University of Tübingen, Tübingen, Germany
5. AO Research Institute Davos, Davos Switzerland