1. University Center for Orthopedics, Trauma Surgery and Plastic Surgery, University Comprehensive Spine Center, University Hospital Carl Gustav Carus Dresden at the TU Dresden, 01307 Dresden, Germany
2. I.R.C.C.S. Istituto Ortopedico Galeazzi, 20161 Milan, Italy
3. National Center for Spinal Disorders, 1126 Budapest, Hungary
4. Department of Neurosurgery, MD Anderson Cancer Center, Houston, TX 77030, USA
5. Department of Neurosurgery, The Warren Alpert Medical School of Brown University, Rhode Island Hospital and The Miriam Hospital, Providence, RI 02903, USA
6. Department of Orthopaedics, Faculty of Medicine, The University of British Columbia, Vancouver, BC V5Z 1M9, Canada
7. Department of Surgery Halbert Chair, Spinal Program University of Toronto, Toronto Western Hospital University Health Network, Toronto, ON M5T 2S8, Canada
8. Department of Neurosurgery, Mayo Clinic, Rochester, MN 55902, USA
9. Department of Neurosurgery, The UCSF Spine Center, University of California, San Francisco, CA 94143, USA
10. AO Spine Knowledge Forum Tumor, AO Spine, 7270 Davos, Switzerland
11. Oxford Spinal Surgery Unit, Oxford University Hospitals, Oxford OX3 7LE, UK