University College London Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK
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Address correspondence to this author at the University College London Institute of Orthopaedic and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, Middlesex, HA7 4LP, UK;
Tel: +44 (0) 7791 025554; Fax: + 44 (0) 7811 942192;
E-mail: wasimkhan@doctors.org.uk