1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
2 Department of Pediatric Orthopaedics Surgery, Children's Hospital Hamburg-Altona, Bleickenallee 38, Hamburg 22763, Germany; Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
3 Department of Pediatric Surgery, Klinik St. Hedwig, University Medical Center Regensburg, Regensburg, Germany.
4 Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
5 Department of Pediatric Surgery, Klinik St. Hedwig, University Medical Center Regensburg, Regensburg, Germany. Electronic address: Michael.Kertai@barmherzige-regensburg.de.
6 Department of Pediatric Orthopaedics Surgery, Children's Hospital Hamburg-Altona, Bleickenallee 38, Hamburg 22763, Germany; Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Electronic address: Martin.Rupprecht@kinderkrankenhaus.net.