[1] Univ Calif San Francisco, Dept Neurol Surg, San Francisco, CA USA
[2] Univ Utah, Dept Neurol Surg, Salt Lake City, UT USA
[3] Mayo Clin, Dept Neurol Surg, Rochester, MN USA
[4] Norton Leatherman Spine Ctr, Louisville, KY USA
[5] Univ Tennessee, Semmes Murphey Neurol & Spine Inst, Dept Neurol Surg, Memphis, TN USA
[6] Indiana Univ, Goodman Campbell Brain & Spine, Dept Neurol Surg, Indianapolis, IN 46204 USA
[7] Univ Virginia, Dept Neurol Surg, Charlottesville, VA USA
[8] Carolinas Healthcare Syst, Neurosci Inst, Charlotte, NC USA
[9] Carolina Neurosurg & Spine Associates, Charlotte, NC USA
[10] Atlantic Neurosurg Specialists, Morristown, NJ USA
[11] Univ Michigan, Dept Neurol Surg, Ann Arbor, MI 48109 USA
[12] Univ Miami, Dept Neurol Surg, Coral Gables, FL 33124 USA
[13] Weill Cornell Med Ctr, Dept Neurol Surg, New York, NY USA
[14] Geisinger Hlth Syst, Danville, PA USA
[15] Vanderbilt Univ, Dept Neurol Surg, 221 Kirkland Hall, Nashville, TN 37235 USA
[16] Atlanta Brain & Spine Care, Atlanta, GA USA