1. Combined Neurosurgical and Orthopedic Spine Service, Department of Orthopedic Surgery, University of British Columbia, Vancouver, British Columbia;
2. Canadian Spine Outcomes and Research Network, Markdale, Ontario;
3. Centre de Recherche CHU de Quebec, CHU de Québec-Université Laval, Quebec City, Quebec;
4. Canada East Spine Centre, Saint John Orthopedics, Dalhousie Medicine New Brunswick, Saint John Campus, Saint John, New Brunswick;
5. London Health Science Centre, Western University, London, Ontario;
6. McGill University Health Centre, Montreal, Quebec;
7. Department of Surgery, Section of Orthopedics and Neurosurgery, University of Manitoba, Winnipeg, Manitoba;
8. Division of Neurosurgery, Department of Surgery, University of Alberta Hospital, Edmonton, Alberta;
9. Department of Surgery, Dalhousie University, Halifax, Nova Scotia;
10. Canada East Spine Centre, Division of Neurosurgery, Zone 2, Horizon Health Network, Saint John, New Brunswick;
11. Sault Area Hospital, Northern Ontario School of Medicine, Sault Ste. Marie, Ontario;
12. Department of Surgery, University of Toronto, Toronto, Ontario;
13. Divisions of Orthopaedic and Neurosurgery, University of Toronto, Toronto, Ontario;
14. The Ottawa Hospital, Ottawa, Ontario;
15. University of Calgary, Calgary, Alberta, Canada