[1] Keele Univ, Dept Trauma & Orthopaed Surg, Sch Med, Stoke On Trent ST4 7QB, Staffs, England
[2] Univ Cagliari, Dept Trauma & Orthopaed Surg, Cagliari, Italy
[3] Univ Roma Tor Vergata, Dept Orthopaed, Rome, Italy
[4] Univ Molise, Dipartimento Sci Salute, Campobasso, Italy