1. Hospital for Special Surgery, New York, NY, USA
2. Department of Orthopaedic Surgery, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Republic of Korea
3. Department of Orthopaedic Surgery, Georgetown University Medical Center, Washington, DC, USA
4. Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, Georgia
5. Columbia Vagelos College of Physicians and Surgeons, New York, NY, USA