1 Cleveland Clinic London Hospital, London, UK; Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, University of Oxford, Oxford, UK.
2 Cleveland Clinic London Hospital, London, UK; Department of Theatres, Anaesthesia and Peri-operative Medicine, Guy's St Thomas' NHS Foundation Trust, London, UK.
3 Cleveland Clinic London Hospital, London, UK; Centre for Nerve Engineering, University College London, London, UK. Electronic address: t.quick@ucl.ac.uk.