1. Departments of Orthopaedic and Neurologic Surgery, NYU Langone Orthopedic Hospital, New York Spine Institute, New York, New York, USA;
2. Department of Orthopedic, Lenox Hill Hospital, Northwell, New York, New York, USA;
3. Department of Neurologic Surgery, University of Michigan, Ann Arbor, Michigan, USA;
4. Spine Institute of Louisiana, Shreveport, Louisiana, USA;
5. San Diego Center for Spinal Disorders, La Jolla, California, USA;
6. Norton Leatherman Spine Center, Louisville, Kentucky, USA;
7. Department of Neurosurgery, University of South Florida, Tampa, Florida, USA;
8. Department of Orthopaedic Surgery, Baylor Scoliosis Center, Dallas, Texas, USA;
9. Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, California, USA;
10. Department of Orthopedic Surgery, SUNY Downstate, New York, New York, USA;
11. Department of Neurosurgery, University of Virginia, Charlottesville, Virginia, USA;
12. Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA;
13. Departments of Neurosurgery and Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA;
14. Department of Orthopaedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA;
15. Department of Orthopaedic Surgery, Swedish Neuroscience Institute, Seattle, Washington, USA;
16. Department of Spine Surgery, Denver International Spine Clinic, Presbyterian St. Luke's/Rocky Mountain Hospital for Children, Denver, Colorado, USA;
17. Department of Orthopaedic Surgery, University of California, Davis, Davis, California, USA;
18. Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri, USA;
19. Departments of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA