[1] Childrens Hosp Los Angeles, 4650 Sunset Blvd,MS 69, Los Angeles, CA 90027 USA
[2] Case Western Reserve Univ, Rainbow Babies & Childrens Hosp, Cleveland, OH 44106 USA
[3] Childrens Hosp, Dept Orthopaed Surg, Boston, MA 02115 USA
[4] Harvard Med Sch, Boston, MA USA
[5] San Diego Ctr Spinal Disorders, La Jolla, CA USA
[6] Univ Calif San Diego, Dept Orthoped Surg, San Diego, CA 92103 USA
[7] Growing Spine Fdn, Milwaukee, WI USA