单侧弹性棒腰椎后路动态固定生物力学分析  

Biomechanical analysis of posterior lumbar dynamic fixation with unilateral elastic rod

作　　者：林慰光[1] 胡奕山[1] 姚迦勒[1] 郑干轩[1] 罗勤瑜[1] 林本丹[1] LIN Wei-guang;HU Yi-shan;YAO Jia-le;ZHENG Gan-xuan;LUO Qin-yu;LIN Ben-dan(Section Ⅰ ,Dept of Orthopaedics,Shantou Central Hospital,Shantou,Guangdong 515031,China)

机构地区：[1]汕头市中心医院骨外一科,广东汕头515031

出　　处：《临床骨科杂志》2021年第5期746-749,共4页Journal of Clinical Orthopaedics

基　　金：广东省汕头市科技局科技创新战略专项资金(纵向协同管理方向)项目(编号:汕府科﹝2018﹞157号-29)。

摘　　要：目的通过生物力学分析单侧弹性棒腰椎后路动态固定在腰椎下关节突不同切除范围时的作用。方法采用8根新鲜成年家猪L3~L6段椎体为材料,测定L4~5运动范围及脊柱前柱应力分布情况。将每个标本依次制成如下7种状态组:A组(完整正常标本)、B组(切除左侧L4下关节突内侧1/2+开窗髓核摘除术)、C组(B组+同侧L4、L5椎弓根钉+弹性棒)、D组(B组+同侧L4、L5椎弓根钉+刚性棒)、E组(切除左侧L4下关节突)、F组(E组+同侧L4、L5椎弓根钉+弹性棒)、G组(E组+同侧L4、L5椎弓根钉+刚性棒)。A组为正常组,B组与E组为损伤组,C组与F组为弹性棒组,D组与G组为刚性棒组。结果切除左侧1/2或左侧全部下关节突时,弹性棒组在屈曲、伸张、侧弯、左旋转的运动范围均小于损伤组(P<0.05),但与正常组比较差异均无统计学意义(P>0.05),右旋转大于正常组(P<0.05)。脊柱前柱应力:在屈曲和侧弯时弹性棒组较刚性棒组增加了6%~13%;弹性棒组内,下关节突切除1/2或全部切除时C组和F组比较差异无统计学意义(P>0.05)。结论单侧弹性棒固定能在绝大部分运动方向上保证脊柱稳定性,并且通过减少应力遮挡,可减缓邻近节段退变。Objective To analyze the role of posterior dynamic fixation with unilateral elastic rod in the different removal ranges of lumbar inferior articular process through biomechanical analysis.Methods The L3~6 vertebral segements of 8 fresh adult domestic pigs were used as materials to measure the motion range(ROM)of L4~5 and the stress distribution of the anterior column of spine.Each specimen was successively made into the following seven state groups:group A(complete normal group),group B(removing the medial 1/2 of the inferior articular process at left lateral L4+fenestration of nucleus pulposus),group C(group B+ipsilateral L4,5 pedicle screw+rigid rod),group D(group B+ipsilateral L4,5 pedicle screw+rigid rod),group E(removing left L4 inferior articular process),group F(group E+ipsilateral L4,5 pedicle screw+elastic rod),group G(group E+ipsilateral L4,5 pedicle screw+elastic rod).Group A was normal group,group B,E were the injured groups,group C,F were the elastic rod groups,group D,G were the rigid rod groups.Results When left lateral 1/2 or total inferior articular process of the left side were removed,under the states of flexion,extension,lateral bending and left rotation,the ROM of the elastic rod groups were smaller than those of the injured groups(P<0.05),while there were statistical differences,compared with the normal group(P<0.05),and the elastic rod groups were larger than the normal group in the ROM of right rotation(P<0.05).The stress of anterior column of spine:under the flexion and lateral bending states,which increased by 6%~13%in the elastic rod groups than the rigid rod groups;in the elastic rod groups,when removing half or total inferior inferior articular process,the stress of spinal anterior column had no statistical differences in group C,F.Conclusions Unilateral elastic rod fixation can ensure spinal stability in most directions of motion,which can relieve adjacent segment degeneration by reducing stress shielding.

关 键 词：单侧弹性棒 腰椎后路 动态固定 生物力学实验 

分 类 号：R-332[医药卫生] R681.5