人体颈椎C7退变性的有限元分析与实验研究

人体颈椎的退变性病变是医学研究的一个重要方面。该文采用数字散斑相关方法(DSCM)对人体颈椎C7及其下位椎间盘进行了动态测试,得到变形演化的全过程。同时采用CT图像完成了颈椎C7的三维重建,建立了有限元分析模型进行退变性和正常条件下的计算。结果表明:在同等外载条件下,退变型颈椎的最大位移和应变水平分别增加42%和134%,最大应力水平下降24%,显示颈椎的退变性将极大地削弱颈椎的抗变形和承载能力。有限元分析和散斑实验结果均显示终板及其附近存在应力集中,有限元分析和散斑实验结果的相符表明了两种方法在生物力学研究方面的可行性。

Expermental and numerical analysis of the degeneration of human cervical C7

The degeneration of cervical vertebra is an important health issue affecting many perple. The dynamic deformations of human cervical C7 and its hypogynous intervertebral disk were measured by the digital speckle correlation method DSCM for the entire deformation process. A 3-D reconstruction of the human cervical C7 was then developed based on CT images and used to build a general finite element method FEM model. The FEM analysis of the degeneration and normal conditions shows that the displacements in the degenerated model were 42% larger and the strains were 134% larger. However, the maximum stresses were reduced by 24% compared with the normal model for the same loading conditions. This study indicates that the degeneration can result in significant weakness against deformation and reduced load-bearing capacity of the cervical vertebra. The FEM and DSCM results both show the stress concentrations on the endplate. The agreement between these two methods shows their usefulness in future biomechanical research.