[1] RWTH Aachen Univ Clin, Dept Orthopaed Surg, Aachen, Germany
[2] Univ Salerno, Dept Med Surg & Dent, Via S Allende, I-84081 Baronissi, SA, Italy
[3] Keele Univ, Sch Med, Sch Pharm & Bioengn, Stoke On Trent, Staffs, England
[4] Queen Mary Univ London, Barts & London Sch Med & Dent, Mile End Hosp, Ctr Sports & Exercise Med, London, England