1. Department of Trauma and Orthopaedics, Guy's and Saint Thomas' NHS Foundation Trust London UK
2. Department of Trauma and Orthopaedics, Countess of Chester Hospital, Cheshire West and Chester Chester UK
3. Department of Neurosurgery, University Hospitals Plymouth NHS Trust Plymouth UK
4. Department of General Medicine, Epsom and St Helier University Hospitals NHS Trust London UK
5. St George's, University of London London UK
6. Leicester Royal Infirmary Leicester UK
7. Department of Trauma and Orthopaedics, Queen Elizabeth Woolwich London UK