1. Spinal Department, Oxford University Hospitals, Headley Way, Oxford, United Kingdom
2. Orthopaedic Department, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, United Kingdom
3. Division of Medical Sciences, Oxford University Clinical Academic Graduate School, Headley Way, Oxford, United Kingdom
4. Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
5. The Centre for Spinal Studies and Surgery, Queen's Medical Centre, Nottingham University Hospitals, Nottingham, United Kingdom