1. Neurosurgery Unit, Department of Clinical Neuroscience, University of Cambridge, UK
2. Vancouver Spine Surgery Institute, Department of Orthopedics, The University of British Columbia, Vancouver, BC, Canada
3. Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ON, Canada
4. Department of Neurosurgery, Medical College of Wisconsin, Wauwatosa, WI, USA
5. Spinal Unit (UVM), Department of Orthopaedics, Centro Hospitalar Universitário do Porto - Hospital de Santo António, Porto, Portugal
6. Instituto de Ciências Biomédicas Abel Salazar, Porto, Portugal
7. Department of Orthopaedics and Traumatology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
8. Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA, USA
9. Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, USA
10. Department of Neurosurgery, Sina Trauma and Surgery Research Center, Tehran University of Medical Sciences, Tehran, Iran
11. Department of Neurosurgery and The Miami Project to Cure Paralysis, The Miller School of Medicine, University of Miami, Miami, FL, USA