[1] Univ Miami, Miller Sch Med, Dept Neurosurg, Miami Project Cure Paralysis, Coral Gables, FL 33124 USA
[2] Univ Pittsburgh, Sch Med Neurosurg, Pittsburgh, PA 15260 USA
[3] Walter Reed Army Inst Res, Silver Spring, MD USA
[4] Univ Miami, Miller Sch Med, Dept Neurol Surg, Miami Project Cure Paralysis, Coral Gables, FL 33124 USA
[5] Univ Florida, Gainesville, FL 32611 USA
[6] Univ Pittsburgh, Sch Med, Safar Ctr Resuscitat Res, Pittsburgh, PA 15260 USA