1. Department of Orthopaedics, Trauma and Plastic Surgery, University Hospital Leipzig, Leipzig, Germany
2. Spine Center, BG Clinic Ludwigshafen, Ludwigshafen, Germany
3. Department of Imaging and Radiation Medicine, Clinic of Radiooncology, University of Leipzig, Leipzig, Germany
4. Orthopedic University Hospital Friedrichsheim, Frankfurt, Germany
5. Medizinische Klinik und Poliklinik I, Universitätsklinikum, Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
6. Department of Orthopaedics and Trauma Surgery, University Hospital Duesseldorf, Duesseldorf, Germany
7. Center for Spinal and Scoliosis Surgery, Malteser Waldkrankenhaus St. Marien, Erlangen, Germany
8. Department of Orthopedics and Traumatology, Paracelsus Private Medical University Nuremberg, Nuremberg, Germany
9. University Comprehensive Spine Center, University Center for Orthopaedics, Trauma and Plastic Surgery, University Hospital Carl Gustav Carus at the TU Dresden, Dresden, Germany