1. U.O.C. of Orthopaedics and Traumatology, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy
2. Department of Human Sciences, Society and Health, University of Cassino and Southern Lazio, 03043 Cassino, Italy
3. Department of Musculoskeletal Disorders, Faculty of Medicine and Surgery, University of Salerno, 84084 Baronissi, Italy