[1] Univ British Columbia, Dept Orthopaed, Div Spine, Vancouver, BC V5Z 1M9, Canada
[2] Univ British Columbia, Vancouver, BC V5Z 1M9, Canada
[3] Rick Hansen Inst, Vancouver, BC, Canada
[4] Univ Toronto, Sunnybrook Hlth Sci Ctr, Toronto, ON, Canada
[5] Univ Toronto, St Michaels Hosp, Spine Program, Toronto, ON, Canada
[6] Univ Laval, Hop Enfant Jesus, Quebec City, PQ, Canada
[7] Univ Ottawa, Ottawa Hosp, Res Inst, Ottawa, ON, Canada
[8] Dalhousie Univ, Horizon Hlth Network, St John, NB, Canada
[9] St Johns Hosp, St John, NB, Canada
[10] Univ Western Ontario, London, ON, Canada
[11] Dalhousie Univ, Halifax, NS, Canada
[12] Hamilton Gen, Hamilton, ON, Canada
[13] McMaster Univ, Hamilton, ON, Canada
[14] Univ Saskatchewan, Saskatoon, SK, Canada
[15] Royal Alexandra Hosp, Edmonton, AB, Canada
[16] Univ Calgary, Spine Program, Calgary, AB, Canada
[17] Univ Manitoba, Dept Surg Orthopaed & Neurosurg, Winnipeg, MB, Canada
[18] Univ Saskatchewan, Dept Phys Med & Rehabil, Saskatoon, SK, Canada
[19] Hop St Justine, Hop Sacre Coeur, Montreal, PQ H3T 1C5, Canada
[20] Univ Toronto, Div Neurosurg & Spinal Program, Toronto, ON, Canada