1. University of Leeds School of Medicine, Academic Department of Trauma and Orthopaedics, Leeds General Infirmary, Great George Street, Leeds, UK
2. Blue Cross Hospital, Cardio-Thoracic Anaesthetic Unit, Thessaloniki, Greece
3. Northwick Patrick Hospital, Maxillofacial Unit, Wattford Road, Harrow, London, UK
4. Imperial College London, Department of Chemical Engineering, South Kensington Campus, London, UK
5. Leeds General Infirmary, Department of Orthopaedics, Great George Street, Leeds LS1 3EX, UK ; ;