1. Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, United Kingdom
2. Department of Orthopedic Surgery, Jichi Medical University, Shimotsuke, Japan
3. Department of Orthopedic Surgery, Chapel Allerton Hospital, Leeds Teaching Hospital NHS Trust, Leeds, United Kingdom
4. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom