腰椎间盘突出症有限元模型的建立与分析

目的建立人体腰椎运动节段(L3~5)有限元模型,于轴向正压力、前屈、侧弯、后伸及旋转等载荷下研究椎间盘的生物力学特征。方法根据健康成年人腰椎运动节段(L3~5)的CT影像学资料,采用Mimics10.0医学图像处理软件和Geomagic10.0逆向工程软件分别建立腰椎运动节段(L3~5)椎体和椎间盘的几何模型,Ansys软件附加腰椎相关韧带及通过改变椎间盘突出后对应的材料属性,构建正常模型和腰椎间盘突出(L34)模型,运用有限元方法模拟正常椎间盘和突出椎间盘于轴向正压力、前屈、侧弯、后伸和旋转等载荷下生物力学特征参数。结果腰椎运动节段(L3,4)发生椎间盘突出后即改变了椎间盘的应力分布及传递载荷能力,应力主要集中于纤维环之后外侧。结论腰椎运动节段(L34)椎间盘突出后椎间盘的承载功能明显下降。

The finite element modeling and analysis of human lumbar segment herniation

Objective To study the biomechanical character of intervertebral disc in different loadings of axial compression, flexion, lateral bending, extension, rotation to develop the finite element (FE) of human lumbar L 3-5 segment. Methods According to CT radiological data of a healthy adult, the vertebra and intervertebral disc of lumbar L 3-5 segment were respectively reconstructed by Mimics 10.0 software and Geomagic 10.0 software. The FE model of L 3-5 segment was reconstructed, and intact disc and herniated lumbar disc were created by adding the lumbar attaching ligaments into the simulating model and changing the corresponding material properties after the disc was extruded in Ansys software. The biomechanical characteristics of two models were simulated under the five loadings of axial compression, flexion, lateral bending, extension and rotation by FE method. Results After the L 3, 4 lumbar disc was extruded, the stress distribution on the disc and the ability of load transfer were changed. The stress was concentrated in the posterior lateral of annulus fibrous. Conclusion After the disc was extruded, the load bearing capacity decreased.