TY - JOUR T1 - Meta-analysis JF - International Journal of Spine Surgery JO - Int J Spine Surg SP - 67 LP - 67 DO - 10.1016/j.esas.2010.07.001 VL - 4 IS - 3 AU - Paul A. Anderson Y1 - 2010/01/01 UR - http://ijssurgery.com//content/4/3/67.abstract N2 - ER -