用三维有限元方法评价并改进全脊椎切除术后内固定模式  

Three-dimensional finite element modeling and biomechanical simulation for evaluating and improving postoperative internal instrumentation of neck-thoracic vertebral tumor en bloc resection

作　　者：赵庆华[1] 李吉鹏[1] 张永兴[1] 梁鹤[1] 王雪鹏[1] 晏鹏[1] 吴小峰[1] 

机构地区：[1]上海交通大学附属第一人民医院骨科,200080

出　　处：《中华医学杂志》2015年第13期978-982,共5页National Medical Journal of China

基　　金：上海科学技术委员会科技支撑资助项目（124119a3402）

摘　　要：目的评价颈胸段骨肿瘤全脊椎切除术后单纯后路固定模型与后路内固定联合前路钢板固定模型两种固定方法的稳定性与应力传导情况。方法采用CT图像和Mimics软件建立C5～他椎体三维模型，模拟C7全脊椎切除术，并分别构建单纯后路固定与后路联合前路内固定模型，将模型导入ANSYS有限元分析系统，施加20N的分布载荷（模拟人体自重）及中性点施加1N·m力矩，模拟前屈、后伸、左，右侧弯、左，右旋转等运动模式下的椎体位移，应力传导及钛网应力分布等情况。结果两种固定模式的相邻椎体位移均小于完整椎体模型，稳定性更佳，两种固定模式之间无明显差异；由于无钢板的应力遮蔽，单纯后路固定模型钛网应力传导效果优于后路联合前路内固定模型，更有利于植骨融合。结论颈胸段肿瘤全脊椎切除术后两种内固定模式均能达到即可的稳定性，而单纯后路长节段固定具有更好的应力传导效果，因此，单纯后路固定在术后重建中更具优势。Objective To employ three-dimensional finite element modeling and biomechanical simulation for evaluating the stability and stress conduction of two postoperative internal fixed modeling- multilevel posterior instrumentation （MPI） and MPI with anterior instrumentation （MPAI） with neck- thoracic vertebral tumor en bloc resection. Methods Mimics software and computed tomography （CT） images were used to establish the three-dimensional （3D） model of vertebrae C5-T2 and simulated the C7 en bloc vertebral resection for MPI and MPAI modeling. Then the statistics and images were transmitted into the ANSYS finite element system and 20N distribution load （simulating body weight） and applied IN · m torque on neutral point for simulating vertebral displacement and stress conduction and distribution of motion mode, i. e. flexion, extension, bending and rotating. Results With a better stability, the displacement of two adjacent vertebral bodies of MPI and MPAI modeling was less than that of complete vertebral modeling. No significant differences existed between each other. But as for stress shielding effect reduction, MPI was slightly better than MPAI. Conclusion From biomechanical point of view, two internal instrumentations with neck-thoracic tumor en bloc resection may achieve an excellent stability with no significant differences. But with better stress conduction, MPI is more advantageous in postoperative reconstruction.

关 键 词：脊椎肿瘤 成像 三维 有限元分析 

分 类 号：R687.3[医药卫生—骨科学]