1. Department of Neurological Surgery, University of California, San Francisco, California;
2. Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota;
3. Atlantic Neurosurgical Specialists, Morristown, New Jersey;
4. Department of Neurological Surgery, University of Utah, Salt Lake City, Utah;
5. Norton Leatherman Spine Center, Louisville, Kentucky;
6. Department of Neurosurgery, University of Tennessee, Memphis, Tennessee;
7. Geisinger Health System, Danville, Pennsylvania;
8. Department of Neurological Surgery, Indiana University, Goodman Campbell Brain and Spine, Indianapolis, Indiana;
9. Department of Neurological Surgery, University of Virginia Health System, Charlottesville, Virginia;
10. Departments of Neurological Surgery and Orthopedic Surgery, Duke University, Durham, North Carolina;
11. Department of Neurological Surgery, Weill Cornell Medical College, New York, New York;
12. Department of Neurologic Surgery, University of Michigan, Ann Arbor, Michigan;
13. Department of Neurologic Surgery, University of Miami, Florida; and
14. Neuroscience Institute, Carolinas Healthcare System and Carolina Neurosurgery & Spine Associates, Charlotte, North Carolina