1. Center for Gait and Motion Analysis, Gillette Children’s Specialty Healthcare, Twin Cities, Minnesota, USA
2. Department of Orthopedic Surgery, Royal Children’s Hospital, Melbourne, Victoria, Australia
3. Department of Orthopedic Surgery and Department of Health Policy and Management, University of Minnesota, Twin Cities, Minnesota, USA
4. Department of Orthopedic Surgery, University of Minnesota, Twin Cities, Minnesota, USA