1. Department of Pediatric Surgery, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
2. Department of Trauma Surgery and Orthopedics, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
3. Department of Trauma Surgery and Orthopedics, Division of Orthopedics, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany