1. Department of Trauma and Orthopaedics, Peterborough City Hospital, Edith Cavell Campus, Bretton Gate, Peterborough, Cambridgeshire, PE3 9GZ, UK
2. Department of Trauma and Orthopaedics, Luton and Dunstable University Hospital NHS Trust, Luton, LU4 0DZ, UK
3. Department of Microbiology, Luton and Dunstable University Hospital NHS Trust, Luton, LU4 0DZ, UK