1. Department of Plastic and Reconstructive Surgery, The Royal London Hospital, Barts Health NHS, Whitechapel Road, London E1 1BB, UK
2. Norwich Medical School, University of East Anglia, Chancellor Drive, Norwich NR4 7TJ, UK
3. Department of Plastic and Reconstructive Surgery, University Hospital Birmingham NHS Foundation Trust, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham, West Midlands B15 2GW, UK