1. Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX3 7LD, UK.
2. Division of Orthopaedic Surgery and the University Musculoskeletal Oncology Unit, Suite 476, Mount Sinai Hospital, 600 University Avenue, Toronto, Canada M5G 1X5.
3. Princess Margaret Comprehensive Cancer Centre, 610 University Avenue, Toronto, Canada M5G 2M9.