1. Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, London, UK
2. Department of Plastic Surgery, Royal Free Hospital, London, UK
3. St Hugh's College, University of Oxford, Oxford, London, UK
4. Department of General and Breast Surgery, Royal Free Hospital, London, UK
5. Department of General Surgery, St Albans City Hospital, St Albans, London, UK