作者单位:Hunter Holmes McGuire VAMC, Spinal Cord Injury & Disorders Ctr, Richmond, VA USA[1]Univ So Mississippi, Sch Human Performance & Recreat, Hattiesburg, MS 39406 USA[2]MedStar Natl Rehabil Network, Washington, DC USA[3]Penn State Univ, Penn State Coll Med, Dept Phys Med & Rehabil, Hershey, PA USA[4]