1. Department of Paediatric Orthopaedic Surgery, University of Turku and Turku University Hospital, Turku, Finland
2. Department of Orthopaedic Surgery, The Johns Hopkins University, Baltimore, Maryland, USA
3. Division of Pediatric Orthopaedic Surgery, Rainbow Babies & Children’s Hospital, Case Western Reserve University, Cleveland, Ohio, USA
4. Department of Orthopaedics and Sports Medicine, Children’s Hospital Colorado, Aurora, Colorado, USA
5. Department of Orthopaedic Surgery, Boston Children’s Hospital, Boston, Massachusetts, USA
6. Department of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
7. Department of Neurosurgery, Shriners Hospitals for Children, Philadelphia, Pennsylvania, USA
8. Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland