1. Department of Pediatrics and Neonatology, San Raffaele Hospital, 20132 Milan, Italy
2. Pediatrics Residency, Vita-Salute San Raffaele University, 20132 Milan, Italy
3. Department of Orthopedics, Regional Health Care and Social Agency, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy
4. Pediatric Orthopedic Unit, Piccole Figlie Hospital, 43125 Parma, Italy