上颈椎有限元模型的建立及分析,以10岁儿童为例

Establishment and Analysis of Finite Element Model of Upper Cervical Spine, an Example of a 10-year-old Boy

本研究以一名10岁龄男童颈椎CT DICOM数据包为例,将数据导入MIMICS进行图像分割处理,得到优化的硬组织表面模型,再导入有限元前处理软件Hypermesh行颈椎C_0~C_2各部分网格的划分、建立颈椎韧带模型并对各部分赋材质、单元属性,建立了颈椎C_0~C_2有限元整体模型,最后导入有限元软件ANSYS14.0中行载荷计算和结论分析。进一步在模拟生理载荷下(颅底垂直加载30 N预压力,1.0 Nm力矩)测定上颈椎模型各节段(C_0~C_1,C_1~C_2)的前屈、后伸、侧屈、旋转的三维运动范围,将所得结论与文献结论进行对比,验证所建模型的有效性。研究表明,本研究成功建立了一个外观逼真的儿童上颈椎有限元模型,模拟生理载荷并测量出上颈椎各节段角位移量,较好的通过了有效性的验证,我们所建立的儿童上颈椎有限元模型几何相似性较好,对进一步用来进行生物力学研究具有重要的参考价值。

The cervical CT DICOM data package of a 10-year-old boy was selected as the material in this study, which w as imported into MIMICS for image segmentation, and the optimized hard tissue surface model was obtained. Then, the finite element pre-processing software Hypermesh was used to segment the mesh sections of the cervical spine C0-C2. We established a cervical ligament model and assigned material and unit attributes to each part, so as to construct the whole model of cervical vertebrae C0-C2 finite element. Finally the finite element model was imput into finite element software ANSYS14.0 to calculate the load and analyze the results. Under the conditions of simulated physiological load （the base of 30 N vertical loading pressure, 1.0 Nm torque） the range of moment of each segment （C0-CI, C1-C2） on flexion, extension, lateral bending and axial rotation was measured, the results of which were compared with the literature results to verify the validity of the model. This study indicated that an artificial finite element model of the upper cervical spine of a child was established successfully. It simulated physiological load and measured the displacement of each segment of the upper cervical spine, and passed the validation of the validity. The normal model of upper cervical spine we built had good geometric similarity and it had important reference value for further research on biomechanics research.