1. Department of Orthopedic Surgery, Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, MD
2. Department of Surgery, United States Naval Hospital, Kuwae, Chatan, Nakagami District, Okinawa Prefecture, Japan
3. Department of Surgery, Uniformed Services University of the Health Sciences, 8901 Rockville Pike, Bethesda, MD
4. Department of Neurological Surgery, University of Washington, 325 9th Ave, Seattle, WA
5. Department of Neurosurgery, Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, MD
6. Department of Neurology, Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, MD