1. Department of Pediatric and Adolescent Medicine, Nordsjællands Hospital, Hillerød, Denmark.
2. Department of Neonatology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
3. Department of Orthopaedic Surgery, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
4. Department of Diagnostic Radiology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.