人体躯干骨骼-肌肉-韧带结构三维有限元模型的建立和验证

Development and Validation of 3D Finite Element Model of Human Trunk

目的:建立正常人体躯干骨-肌肉-韧带三维有限元模型,为脊柱部生物力学研究提供数字平台。方法:获取正常青壮年男性的躯干螺旋CT扫描图像,应用逆向工程原理,通过Mimics、Geomagic软件建立躯干骨结构的三维几何模型;利用ANSYS10.0对其进行有限元网格划分,椎间盘、韧带和肌肉根据解剖学和文献数据模拟,并参照以往文献报道对模型的可靠性进行验证。结果:建立了包括374618个实体单元,110102个壳单元,427个Link单元,22个质点单元,共65998个节点的关节、椎骨、椎间盘和韧带的躯干部三维有限元模型,根据CT灰度值和杨氏模量关系式对松质骨、皮质骨和后部结构进行单独材料赋值,采用等效法构建椎间盘的纤维环。结论:运用逆向工程原理可有效构建人体躯干的三维几何模型,在此基础上基于解剖和离体标本实验结果构建其生物力学有限元模型,可用于人体脊柱生物力学变化规律的可视化分析。

Objective To provide a digital platform for biomechanics research of human spine.Methods A 3D solid model of axial skeleton of healthy young-middle aged adults was established through helical CT images according to the principles of reverse engineering（RE）.The reliability of the model was validated through the literature reviews.Results An axial skeleton model,including joints,vertebrae,intervertebral discs（IVD）and ligaments,was constructed which composed of 374618 units,110102 shell elements,427 link elements and 22 particle units with a total of 659982 nodes.According to the relationship of the CT Hounsfield value and Young’s modulus,the mean Young’s modulus of vertebrae cancellous bone and posterior element were calculated.The model of annulus fibrosis of IVD was simplified by assigned an equivalent material property.Conclusion Construction of human trunk 3D geometric model based on the RE principle is optimized through the anatomical data and biomechanical experiments,and a 3D finite element model was finally developed for further biomechanic research of spine.