1. Gait Analysis Laboratory, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Road, 19803, Wilmington, DE USA
2. Department of Orthopaedics, Children’s Hospital of Brabois, Nancy France
3. Department of Orthopaedics, Henri Poincaré University, Nancy France
4. Nemours Biomedical Research, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE USA