1. Department of Neurosurgery, University of Virginia Health System, Charlottesville, Virginia;
2. Norton Leatherman Spine Center, Louisville, Kentucky;
3. Hospital for Joint Diseases, NYU Langone Medical Center, New York;
4. Department of Neurosurgery, Weill Cornell Medical College, New York, New York; and
5. Spinal Deformity Service, Washington University in St. Louis, Missouri