[1] Rocky Mt Scoliosis & Spine, Dept Orthoped, Rocky Mt Hosp Children, Presbyterian St Lukes Med Ctr, Denver, CO 80205 USA
[2] NYU, Hosp Joint Dis, Dept Orthoped, New York, NY 10003 USA
[3] Univ Virginia, Dept Neurol Surg, Charlottesville, VA 22908 USA
[4] Univ Virginia, Dept Orthopaed Surg, Charlottesville, VA 22908 USA