1. Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA
2. Department of Orthopaedic Surgery and Biomedical Engineering, University of Tennesse – Campbell Clinic Orthopaedics, Memphis, TN, USA
3. Department of Orthopaedic Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
4. Department of Orthopaedic Surgery, University College London Hospitals, London, UK
5. Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO, USA