3Okuda S, lwasaki M, Miyauchi A, eL al. Risk factors for adjacentsegment d egenration after PILF [ J ]. Spine, 2004, 29 ( 14 ) : 1535 - 1540.
4Suk K S, Lee H M, Kim N H, et al. Unilateral versus bilateral pedicle screw fixation in lumbar spinal fusion [ J ]. Spine,2000,25 (14) :1843 - 1847.
5Femandez-Fairen M, Sala P, Ramirez H, et al. A prospective randomized study of unilateral versus bilateral instrumented pos- terolateral lumbar fusion in degenerative spondylolisthesis [ J ]. Spine,2007,32(4) :395 -401.
6Chen H H, Cheung H H, Wang W K, et al. Biomechanical analysisof unilateral fixation with interbedy cages [ J ]. Spine, 2005,30 (4) :E92 -96.
7Sehleieher P, Beth P, Ottenbaeher A, et al. Biomechanieal evalu- ation of different asymmetrical posterior stabilization methods for minimally invasive transforaminal lumbar interbody fusion [ J ]. J Neurosurg Spine ,2008,9(4) :363 - 371.
