[1] Louisiana State Univ, Dept Orthoped, Baton Rouge, LA 70803 USA
[2] McGill Univ, Hlth Ctr, Div Orthoped, 1650 Cedar Ave, Montreal, PQ H3G 1A4, Canada
[3] Brown Univ, Dept Neurosurg, Providence, RI 02912 USA
[4] Johns Hopkins Univ, Dept Neurosurg, Baltimore, MD USA
[5] Univ Utah, Dept Neurosurg, Salt Lake City, UT USA
[6] MD Anderson Canc Ctr, Dept Neurosurg, Houston, TX USA
[7] Toronto Western Hosp, Div Neurosurg, Toronto, ON, Canada
[8] Mem Sloan Kettering Canc Ctr, Dept Neurosurg, 1275 York Ave, New York, NY 10021 USA
[9] Mayo Clin, Dept Neurol Surg, Rochester, MN USA
[10] Mt Sinai Med Ctr, Dept Neurosurg, New York, NY 10029 USA
[11] Univ Med Ctr Utrecht, Dept Orthoped Surg, Utrecht, Netherlands
[12] Univ Toronto, Odette Canc Ctr, Dept Radiat Oncol, Toronto, ON, Canada
[13] Univ Calif San Francisco, Spine Ctr, Dept Neurosurg, San Francisco, CA 94143 USA
[14] Univ British Columbia, Vancouver Spine Surg Inst, Vancouver, BC, Canada