重度脊柱侧弯三维有限元模型模拟脊柱后路矫形术生物力学特点  

Establishment of Three-dimensional Finite Element Model for Severe Rigid Scoliosis and Biomechanical Analysis of PVCR

作　　者：张颖[1] 王迎松[1] 解京明[1] 赵智[1] 李韬[1] 毕尼[1] ZHANG Ying;WANG Ying-song;XIE Jing-ming;ZHAO Zhi;LI Tao;BI Ni(Dept. of Orthipedics,The 2nd Affiliated Hospital of Kunming Medical University,Kunming Yunnan 650101,China)

机构地区：[1]昆明医科大学第二附属医院骨科,云南昆明650101

出　　处：《昆明医科大学学报》2019年第4期31-36,共6页Journal of Kunming Medical University

基　　金：云南省科技厅-昆明医科大学应用基础研究联合专项基金资助项目(2015FB053)

摘　　要：目的建立严重僵硬性脊柱侧弯的三维有限元模型,在该模型上模拟经后路全椎体切除术(posterior vertebral column resection,PCVR)并分析其生物力学特点。方法以1例严重僵硬性脊柱侧弯患者CT为基础,使用Mimics10.01,Geomagic studio12,UG8.0等软件建立,优化俯卧位严重脊柱侧弯的三维有限元模型。验证模型与患者原始资料的几何相似性以及力学有效性。利用模型模拟PVCR术。结果成功建立严重僵硬性脊柱侧弯的三维有限元模型,并验证该模型有效。利用模型完成PVCR术模拟。椎体切除后,断端在轴位、冠状位及矢状位均有移位趋势;术后矫形棒应力值区间为:0.0050214e^7 ～0.045217e^7 Mpa,应力值最大区域为截骨区及上下2个椎体,其应力值为0.045217e^7 Mpa,应力最小为端椎区域,为:0.0050214e^7 ～0.025121e^7 Mpa。螺钉应力值区间:3.1108e^7 ～2.7961e^8 Mpa,其中切除椎体的上位椎体凸侧第1枚螺钉应力最大,为2.4577e^8 Mpa。术后端椎区域T2/3及T7/8、T8/9、T9/10椎间盘上的应力较大,椎间盘受力最大区域均位于纤维环。结论 PVCR椎体切除区域,断端呈三维位移趋势,增加医源性脊髓损伤的风险;该区域内植物负荷最大,是术后发生内植物损耗的易发区域;术后交界区椎间盘承载较大应力且较集中,易出现交界区病变。Objective To establish the three-dimensional finite element model of severe rigid scoliosis , so as to simulate PVCR operation to explore the biomechanical characteristics. Methods The three-dimensional finite element model of severe rigid scoliosis was established by Mimics10.01 software,Geomagic12,UG8.0 3D modeling software and Workbench finite element analysis software. Effectiveness of model was verified by CSVL. The model was used to simulate the PVCR surgery. Results After the vertebral body was resected, there were three dimensional displacements between two segments. The stress range of orthopedic bar after simulated PVCR orthopedic surgery was 0.0050214 e7 MPa - 0.045217 e7 MPa. The maximum stress area located in the area of vertebrae above and below the osteotomy area and the osteotomy area. The stress value is 0.045217 e7 MPa. The stress range of orthopedic screws was 3.1108e7 MPa - 2.7961e8 MPa. The largest area of stress is pedicle area. The stress of the first orthopedic screw was 2.4577e8 MPa under the excised vertebral column. The first screw in the convex side cranial to the excised vertebral loaded the maximum stress which was 2.4577e8 MPa. The stress on the T2/3, T7/8, T8/9 and T9/10 of the intervertebral disc was larger than that of the other intervertebral discs. Conclusion During PVCR procedure, the 3 dimensional displacements between two segments were related to iatro genic spinal cord injury. The implant loaded much more stress in the area of osteotomy than in other area, which can lead to postoperatively implant failure. The stress on the intervertebral disc in the area of junktional were larger than that of the other intervertebral discs, which can lead junctional disorders.

关 键 词：脊柱侧弯 三维有限元 经后路全脊椎切除 

分 类 号：R682.1[医药卫生—骨科学]