1. Department of Trauma and Orthopaedics, Imperial College Healthcare NHS Trust, London, UK
2. Department of Trauma and Orthopaedics, Lister Hospital, East and North Hertfordshire NHS Trust, Stevenage, UK
3. Department of Trauma and Orthopaedics, The Whittington Health/University College London Hospitals NHS Foundation Trust, London, UK
4. Department of Trauma and Orthopaedics, Chelsea and Westminster NHS Foundation Trust, London, UK