1. Center for Orthopaedics, Trauma Surgery and Rehabilitation Medicine, University Medicine Greifswald, 17475 Greifswald, Germany
2. Orthopedic Department, Jena University Hospital, Campus Eisenberg, 07607 Eisenberg, Germany
3. Diakonieklinikum Stuttgart, Department of Orthopaedic and Trauma Surgery, Orthopädische Klinik Paulinenhilfe, 70176 Stuttgart, Germany