1. The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
2. Department of Orthopaedic Surgery, William Beaumont Army Medical Center, El Paso, Texas, USA
3. Texas Tech University Health Sciences Center, El Paso, Texas USA
4. Department of Orthopaedic Surgery, Carthage Area Hospital, Carthage, New York, USA
5. Claxton-Hepburn Medical Center, Ogdensburg, New York, USA
6. Carson Tahoe Health Administration, Carson City, Nevada, USA