1. Department of Orthopaedic Surgery, University Hospital Heraklion, Crete, 71500 Heraklion, Greece
2. Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland
3. Department of Orthopaedic Surgery, Center for Orthopaedics, Traumatology and Spinal Cord Injury, Heidelberg University Hospital, 69118 Heidelberg, Germany