胸腰段三维非线性有限元建模及临床意义

目的建立胸腰段三个椎体节段的三维非线性有限元模型并对模型的有效性进行验证。方法建立T12/L1/L2三个椎体节段的三维非线性有限元模型,该模型分别在垂直压缩力800N作用下,屈曲、后伸、侧弯、扭转力矩作用下,最大力矩皆为16N·m,分析模型的平均刚度、屈曲和后伸力矩与旋转角度的关系,观察椎间盘纤维环上的应力分布情况。结果模型的平均刚度及力矩-旋转角度关系曲线和其他作者的实测法所得结果基本一致;椎间盘纤维环上应力符合临床和其他作者有限元分析所得结果。结论本研究通过一种改良的测量建模法建立的胸腰段有限元模型符合脊柱生物力学的一般特点,可以对胸腰段和胸腰段内固定的生物力学进行研究。

Three-dimensional Nonlinear Finite Element Models of Thoracolumbar Spine and Its Clinical Significance

Objective To design a three-dimensional nonlinear finite element for a three-vertebra segment of thoracolumbar and veri-fy its efficiency.Methods Three-dimensional nonlinear finite element analysis was performed on T12/L1/L2vertebral segments,subjected to vertical compression force of800N,flexion?extension?lateral bending and torsion moments of16N-m,then,analyzed mean stiffness of model and dependence of flexion?extension moments and rotation degree,observed stresses in the intervertebral disc fibers.Re sults The mean stiffness and dependency curve of flexion?extension moments and rotation degree of our model were very close to those of the experimental test from different authors;The stresses in the intervertebral disc fibers of our model were very close to those of the experimental test and the finite element analysis from different authors.Conclusion Our model conforms to general biomechanical characteristic of spine and it will be a valuable simulation tool for biomechanical study of spinal disorders and spinal implants.