1. Department of Orthopaedic Surgery, William Beaumont Army Medical Center, El Paso, Texas, USA.
2. Department of Orthopaedic Surgery, Walter Reed National Military Medical Center, Bethesda, Maryland, USA.
3. Department of Orthopaedic Surgery, Keller Army Hospital, United States Military Academy, West Point, New York, USA.
4. Department of Orthopaedic Surgery, The Orthopedic Specialty Hospital, Mercy Medical Center, Baltimore, Maryland, USA.
5. Department of Orthopaedic Surgery, Brown University Alpert Medical School, Providence, Rhode Island, USA.