Comparision Of The Facet Joint Bio Mechanical Changes Of Lumber Spine After Unilateral Pedicle Screw Fixation And Simple Decompression

Objective: Explore the different surgical procedures on the opposite sideof the lumbar facet biomechanical and clinical significance, in order tograsp the clinical indications for surgery lumbar degenerative disease, areasonable choice of surgical and internal fixation devices providebiomechanical basis.Methods:6T12-L5fresh calf spine specimens.Simulation of L4-L5lumber degeneration model, and give similar operation disposalsproceedingly：unilateral fenestration decompression (ipsilateral internal1/3facetectomy), simple unilateral pedicle screw fixation（unilateral facetjoints discectomy）and unilateral pedicle screw fixation with interbodyfusion. To simulate the biological function of human，give the specimensflexion, extension test,do the strain measurement of different pointsaround the contralateral facet（including L3inferior，L4superior andinferior，L5superior） data by the help of the electronical universaltesting machine.SPSS16.0software package was used for data analysis,data differences among the groups were compared using Sceffe method.(P＜0.05, there was significant difference).Results:Statistical analysis of the measured unilateral fixation group inflexion extension load operation facet joint around the strain is morethan simple fenestration group and control group, the difference wassignificant. Conclusions:Unilateral pedicle screw fixation alone is not enough toprovide sufficient biomechanical stability. Unilateral pedicle screwfixation and interbody fusion can provide satisfactory biomechanicalstability.