1. Department of Neurological Surgery, University of Pittsburgh School of Medicine
2. Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
3. Department of Neurosurgery, University of California, San Francisco, San Francisco, CA
4. Department of Neurologic Surgery, Mayo Clinic, Rochester, MN
5. Department of Neurosurgery, Columbia University Irving Medical Center, New York City, NY
6. Department of Neurological Surgery, Medical College of Wisconsin, Milwaukee, WI
7. Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA
8. Department of Neurological Surgery, University of Miami, Miami, FL
9. Atlanta Brain and Spine Care, Atlanta, GA
10. Atlantic Neurosurgical Specialists, Morristown, NJ
11. Department of Neurosurgery, University of Utah, Salt Lake City, UT
12. Department of Neurosurgery, Duke University, Durham, NC
13. Department of Neurological Surgery, Weill Cornell Medical Center, New York, NY
14. Norton Leatherman Spine Center, Louisville, KY
15. Department of Neurosurgery, University of Virginia, Charlottesville, VA
16. Department of Neurosurgery, Semmes-Murphey Neurologic and Spine Institute, University of Tennessee, Memphis, TN
17. Department of Neurological Surgery, Washington University School of Medicine in St. Louis, St. Louis, MO
18. Neuroscience Institute, Carolina Neurosurgery & Spine Associates, Carolinas Healthcare System, Charlotte
19. Department of Neurosurgery, University of North Carolina School of Medicine, Chapel Hill, NC
20. Department of Neurological Surgery, Goodman Campbell Brain and Spine, Indianapolis, IN
21. Department of Neurosurgery, Barrow Neurologic Institute, Phoenix, AZ