1. Orthopedic and Traumatology Unit, University of Perugia, “Santa Maria della Misericordia” Hospital, P.le G. Menghini 3, 06156 Perugia, Italy
2. Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy