1. Gaetano Pini Orthopaedic Institute, Milan, Italy
2. Clinica Ortopedica, Azienda Sanitaria Universitaria Integrata di Udine, Udine, Italy
3. Orthopaedic Clinic, University of Florence, Florence, Italy
4. Department of Orthopaedics and Traumatology, Humanitas Gavazzeni Hospital, Bergamo, Italy
5. Orthopaedic Department, San Gerardo Hospital, University of Milano-Bicocca, Monza, Italy
6. San Carlo di Nancy GVM Care and Research, Rome, Italy
7. Rome American Hospital, Rome, Italy
8. Hip Department and Trauma, IRCCS Policlinico San Donato, S. Donato Milanese, Milan, Italy
9. Hip Department I.R.C.C.S. Istituto Clinico Humanitas, Milan, Italy
10. Department of Medical Area, University of Udine, Udine, Italy