1. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Science, Oxford, UK
2. Kings College Hospital NHS Trust, London, UK
3. Oxford University Hospitals NHS Trust, Oxford, UK
4. University College London Hospital NHS Trust, London, UK
5. Buckinghamshire NHS Healthcare Trust, Amersham, UK
6. Whipps Cross Hospital, Barts Health NHS Trust, London, UK
7. Northampton NHS Trust, Northampton, UK
8. Queen Victoria Hospital NHS Trust, East Grinstead, UK