The Effect Of Cage Position On Radiological And Clinical Outcomes After PLIF Of L4-5

ObjectiveFirst,to investigate the influence of different cage positions on the imaging and clinical results after posterior lumbar interbody fusion(PLIF),so as to provide a theoretical basis for determining the optimal placement of cage in lumbar fusion.Second,analyze the difference of clinical effect and imaging indexes before and after PLIF for lumbar degenerative diseases.MethodsThe imaging and clinical data of 71 patients who underwent single segment PLIF from January 1,2021 to October 31,2022 were collected.The subjects selected L4-5segment for PLIF and used the same type of fusion cage.The specification of fusion device is H10 mm × W11 mm × L22mm。Cage Position(CP)can be expressed by the ratio(x/y)of the distance from the center of the cage to the anterior edge of the vertebral body(x)to the length of the upper endplate of the L5 vertebral body(y);The center point of the cage to the midpoint of the line between the marker point at the rear of the cage and the marker point at the front of the cage.VAS,JOA scores and lumbar CT imaging data were collected and evaluated before and after operation.The preoperative and postoperative pain scores,anterior and posterior intervertebral space height,left and right intervertebral foramen height,segmental lordosis angle,lumbar lordosis angle and other aspects of each group were retrospectively studied.Statistical methods such as ANOVA(single factor),independent sample T test,paired sample T test,nonparametric test and chi square test were used for data analysis.ResultsThere was no significant difference in the general data of subjects such as age,height and weight between the front group and the post group(P>0.05).In terms of clinical efficacy score indicators,the VAS and JOA scores of the postoperative and the last follow-up groups in the front and post groups were significantly improved compared with the preoperative scores(P <0.05);When comparing between groups,there was no significant difference in VAS and JOA scores between the two groups before,after and at the last follow-up(P>0.05),that is,the location of the fusion cage did not affect the efficacy of PLIF.After operation,the imaging parameters of ADH,PDH,AvDH,LFH,RFH,SL,LL were increased compared with those before operation,and had statistical significance(P<0.05).There was no significant difference in ADH,PDH,AvDH,LFH,RFH,LL between the anterior group and the posterior group(P>0.05),that is,when using the same type of fusion cage,the different positions of the anterior and posterior fusion cages did not affect the size of ADH,PDH,AvDH,LFH,RFH,LL;However,there was a significant statistical difference between the anterior group and the posterior group in the segmental lordosis(SL)ConclusionFirst,the anterior and posterior position of the fusion cage after PLIF affects the lumbar segmental lordosis(SL).When Cage is located in the front of the intervertebral space,a larger SL can be obtained,which is conducive to the reconstruction of the postoperative SL.Second,the anterior and posterior position of fusion cage after PLIF does not affect ADH,PDH,AvDH,LFH,RFH,LL.Third,patients in both the anterior and posterior groups of PLIF fusion cages can obtain better clinical effects.