[1] Northwestern Univ, Rehabil Inst Chicago, Evanston, IL 60208 USA
[2] Stanford Univ, Dept Orthoped, Palo Alto, CA 94304 USA
[3] Univ Pittsburgh, Med Ctr, Dept Phys Med & Rehabil, Pittsburgh, PA 15260 USA
[4] Kaiser Permanente, Dept Phys Med & Rehabil, Oakland, CA USA
[5] Univ Kansas, Med Ctr, Kansas City, KS 66103 USA
[6] Univ Hosp West Indies, Kingston, Jamaica
[7] Alegent Hlth Syst, Sports & Spine Rehabil Ctr, Omaha, NE USA
[8] Univ Penn, Dept Rehabil Med, Philadelphia, PA 19104 USA