新型外固定支架系统-胫骨骨折模型的建立与三维有限元分析

Establishment and finite element analysis based on model of new external fixator on tibial fracture

摘要:

目的建立新型外固定支架系统在胫骨骨折模型上的有限元模型，分析评价有限元模型建立的可行性及力学分布特点，为进一步的材料结构优化及临床应用提供理论支持。方法利用Mimics17.0 软件将新鲜尸体的胫骨CT 数据导入并建立胫骨模型，用Hypermesh 对模型进行网格划分并导入有限元分析软件ABAQUS6.13，施加轴向载荷后观察Von-Mises 应力分布和骨折断端位移情况，通过与生物力学结果对比评价其生物力学特点。结果成功创建了装配体有限元模型，生成548 101 个体单元，节点548 101 个。最大轴向载荷下骨折断端最大位移为1.16 mm，最大Von mises 应力分布点为骨针接触面。结论有限元模型的建立及分析方法能较好地反映该新型外固定支架胫骨骨折系统的生物力学分布情况，可为进一步临床应用提供理论基础。

Abstract:

Objective To create a finite element model of the newly-developed external fixator system on tibial fracture and then to evaluate its mechanical stability by comparing the mechanics experimental data results, so as to provide a theoretical basis for further clinical application and structure optimization. Methods A tibia was selected from a fresh cadaver without bone lesions. The tibia model was created on the basis of CT images through Mimics17.0 medical imaging interactive software. Hypermesh software was used to mesh the assembly model and then finite element analysis was made with ABAQUS6.13 software. After giving axial load, the Von Mises stress distribution and displacement of the end of the tibial fracture were observed with the new external fixator model,then the biomechanical stability was evaluated. Results A 3D finite element model of a newly-developed external fixator-tibial fracture assembly was successfully created, which could create 548,101 individual units and 548,101 nodes. With the maximum axial load, the maximum Von -mises stress distribution points were on the spicule interface and the maximum displacement of the tibial fracture was 1.16 mm. Conclusions The newly-developed external fixator-tibial fracture finite element model can better reflect the distribution of biomechanics of tibia. It could provide a theoretical basis for further clinical application of external fixator.