不同植入物固定L1节段爆裂性骨折的三维有限元分析

背景：胸腰段椎体爆裂性骨折临床十分常见，通过前路或者后路内固定重建稳定是日前常用的方法，作者未A及有关内固定应力情况的相关报道。目的：通过三维有限元法分析在L1节段爆裂性骨折情况下前路钛网重建钉棒内固定和后路椎弓根内固定两种方式中内固定物应力的分布情况，并进行两种方式稳定性的比较。方法：选择1名健康男性志愿者，通过CT扫描和有限元软件建立T12-L2节段的三维有限元模型。在验证彳丁效的彳丁限元模型上分别模拟L1节段爆裂性骨折，建立前路L，节段钛网重建钉棒内固定模型（模型A）和后路短节段椎弓根钉棒内固定模型（模型B），在各模型上施加载荷，观察内固定应力分布情况，进行稳定性的比较。结果与结论：建立T12-L2节段的三维有限元模型。两种内固定方式有限元模型_任不同载荷实验中，模型A应力：蔓婴集中在钛网区域，模型B应力主要集中在钉棒的交接处。模型A的稳定性优于后者，模型A的T12平而的甲均应力值小于模型B，差异有显著性意义（P〈0．01）。说明前路术后钛网发生沉降和后路术后钉棒处断裂均可能与局部应力集中有关。前路钛网重建钉棒内固定较后路椎弓根内固定稳定性更好。

Three-dimensional finite element analysis on different implant fixation for L1 segment burst fracture

BACKGROUND： Thoracolumbar burst fracture is a common injury in clinic. Inner fixation surgery through anterior and posterior approach is the commonly used method to rebuild the stability. The stress distribution has not been reported in literature. OBJECTIVE： To investigate the stress distribution of internal fixation materials in titanium mesh reconstruction screw-rods system fixation and posterior approach screw-rods system fixation for the treatment of L1 segment burst fracture by three-dimensional finite element analysis, and to compare the stability of these two methods. METHODS： One healthy male volunteer was selected to establish the T12-L2 segment three-dimensional finite element model through CT scan and finite element software. The L1 segment burst fracture was simulated on the effective finite element model to establish the anterior approach L1 segment titanium mesh reconstruction combine screw-rods system fixation （model A） and posterior approach short segment screw-rods system fixation （model B）, the load was applied on the models in order to observe the stress distribution and compare the stability. RESULTS AND CONCLUSION： A T~2-L2 segment three-dimensional finite element model was established. In the loading experiment, the stress of model A was mainly in the titanium mesh area and the stress of model B was mainly concentrated in the screw-rod junction. Both model A and model B could gain valid stability in reconstruction of L~ segment burst fracture, and the former was better than later. Mean stress in T12 plane of model A was less than that of model B, and the difference was statistically significant （P 〈 0.01 ）. Titanium mesh deposition after anterior approach and screw-rod fracture after posterior approach may relate with local stress concentration. The anterior approach titanium mesh reconstruction combine screw-rods system fixation has the better stability than posterior approach screw-rods system fixation.