1. Department of Orthopedic and Trauma Surgery, Marien Krankenhaus GmbH, Bergisch Gladbach, Germany
2. Department of Orthopedic and Trauma Surgery, University of Cologne, Cologne, Germany
3. Department of Orthopedic and Trauma Surgery, Medizinisches Zentrum StädteRegion Aachen GmbH, Mauerfeldchen, Würselen, Germany