个体化侧凸躯干骨和骨盆有限元模型的建立

Development of the personalized finite element model of the trunk and pelvis

目的建立个体化青少年特发性脊柱侧凸（AIS）患者躯干骨（颈椎除外）和骨盆的三维有限元模型。方法采用螺旋CT扫描AIS患者，共513层，经一系列图像软件处理，数据以IG—ES文件格式转入有限元分析软件ANSYS8．0，建立AIS躯干骨（颈椎除外）和骨盆的三维几何模型，继而选择单元，赋予材料物理属性，划分网格，建成了有限元模型。根据临床实验的数据，对模型材料属性进行修正。修正后模型初步用来分析支具治疗的生物力学特点。结果模型单元采用了4种单元类型，13种材料性质，共划分234338个单元，261095个结点，模型外观逼真，模型生物力学行为和真实情况相符合。模拟支具的的盐线变化与临床观察比较，误差为2．8％。结论基于CT扫描数据，可以建立高仿真的形态和材料性质均个体化的侧凸躯干骨和骨盆的有限元模型。

Objective To develop personalized finite element （FE） model of trunk （excluding cervical） and pelvis of adolescent idiopathic scoliosis （A/S）. Methods The data of one patient with AIS were obtained by using spiral computed tomography （CT）. By using a series of computer aided design （CAD） software,3D FE model of AIS was developed. For the personalization of the model,the E-module was optimized based on the clinical bending test. Then, optimized model was applied to simulate the brace treatment of AIS. Results The FE model of AIS included 4 types of elements, 13 kinds of material properties,234338 elements and 261095 nodes. The model had a similar appearance with reality. Biomeehanics behavior of the model was agreement with the clinical observation. The difference of the curve deformation between the simulation and clinical result was 2.8%. Conclusion Based on the data from CT, a FE model of AIS is developed,which is personalized not only in geometry but also in material property.