1. Department of Physical Medicine and Rehabilitation, The Center for Rehabilitation Sciences Research, Uniformed Services University of Health Sciences, Bethesda, MD
2. Department of Rehabilitation, Walter Reed National Military Medical Center, Bethesda, MD
3. The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD
4. Department of Orthopaedic Surgery, Walter Reed National Military Medical Center, Bethesda, MD