全腰椎非线性有限元模型的建立与有效性验证

目的　为人体腰椎生物力学有限元分析建立有效的全腰椎非线性数字仿真模型。 方法　采集一名25岁的健康男性腰椎（L1~5）CT影像数据，依次通过Mimics 17.0、Geomagic Studio 2013、UG8.5、Hypermesh 13.0、Abaqus6.14-4五个软件建立模型，赋予各组织对应的属性。首先进行网格收敛性测试，选取合适的网格划分方案以提高分析效率。然后通过给模型施加不同的力矩载荷来模拟腰椎的6种运动（前屈、后伸、左侧弯、右侧弯、左轴向旋转、右轴向旋转），计算腰椎各功能节段（functional spinal unit，FSU）的活动度（range of motion，ROM）。 结果　模型得出的结果与体外试验的数据类似，两者变化趋势规律一致。 结论　本研究使用的全腰椎非线性有限元模型的建立与验证方法可用于未来脊柱相关疾病的建模与分析。

Development and validation of nonlinear finite element model of the whole lumbar spine

Objective 　To develop the whole lumbar spine finite element model and to validate the model by comparison with the previous vitro experiments. results.　Methods　The CT images of the whole lumbar spine were from a 25 years old male volunteer. The finite element model was established by six software: Mimics 17.0, Geomagic Studio 2013, UG8.5, Hypermesh 13.0 and Abaqus 6.14-4. After finishing a grid convergence test, six lumbar movements (flexion, extension, left bending, right bending, left axial rotation, right axial rotation) were simulated by applying different moment loads to the model. Then the range of motion (ROM) of each lumbar spine functional spinal unit (FSU) was recorded.　Results　The simulating results obtained by the model were similar to those obtained from the in-vitro experiments, and the trend of the two was consistent.　Conclusions　The establishment and validation of the nonlinear finite element model of the whole lumbar spine used in this study can be used to model and analyze future spine-related diseases.