1. Department of Orthopaedic Surgery, Broomfield Hospital, Mid and South Essex NHS Foundation Trust, London, UK
2. Department of General Surgery, North Middlesex University Hospital, London, UK
3. Department of Orthopaedic Surgery, Princess Royal University Hospital, Orpington, UK
4. Department of Orthopaedic Surgery, Barnet Hospital, Royal Free London NHS Foundation Trust, Barnet, UK
5. Department of Orthopaedic Surgery, Great Western Hospital, Swindon, UK