正常人下颈椎C_(4～7)节段三维有限元模型的建立与验证

Development and Validation of a Three-Dimensional Finite Element Model of Inferior Cervical Spinal Segments C_(4-7) for a Healthy Person

本研究基于计算机断层扫描（CT）图像数据建立并验证正常人颈椎C4-7三维有限元模型,为研究中医手法治疗颈椎慢性疾病的生物力学机制提供模型平台。基于受试者颈部CT图像,依次运用Mimics 17.0、Geomagic12.0及Abaqus 6.13等软件创建正常人C4-7节段有限元模型。在模型上分别模拟前屈、后伸、左右侧弯和左右旋转工况,计算椎体间相对动度（ROM）,将计算的结果与文献结果进行对比分析,并观察模型在1Nm载荷下6种工况下模型的主要应力分布情况。本研究成功建立了正常人颈椎C4-7三维有限元模型,共包含591 459单元、121 446节点,模拟了椎体、椎间盘、韧带、关节等几何结构与材料特性。模型在前后屈伸、左右侧弯和左右旋转6种工况下的ROM与实验研究数据基本一致,在1Nm扭矩或弯矩载荷下,模型主要应力分布基本反映了正常人颈椎生理活动时的主要应力分布情况。本研究建立的正常人颈椎C4-7三维有限元模型精确逼真,符合颈椎的生物力学特性,可用于研究中医手法治疗颈椎慢性疾病的生物力学分析。

This study aims to develop and validate a three-dimensional finite element model of inferior cervical spinal segments C4-7of a healthy volunteer,and to provide a computational platform for investigating the biomechanical mechanism of treating cervical vertebra disease with Traditional Chinese Traumotology Manipulation（TCTM）.A series of computed tomography（CT）images of C4-7segments were processed to establish the finite element model using softwares Mimics 17.0,Geromagic12.0,and Abaqus 6.13.A reference point（RP）was created on the endplate of C4 and coupled with all nodes of C4.All loads（±0.5,±1,±1.5and±2Nm）were added to the RP for the six simulations（flexion,extension,lateral bending and axial rotation）.Then,the range of motion of each segment was calculated and compared with experimental measurements of in vitro studies.On the other hand,1Nm moment was loaded on the model to observe the main stress regions of the model in different status.We successfully established a detail model of inferior cervical spinal segments C4-7of a healthy volunteer with 591 459 elements and 121 446 nodes which contains the structure of the vertebra,intervertebral discs,ligaments and facet joints.The model showed an accordance result after the comparison with the in vitro studies in the six simulations.Moreover,the main stress region occurred on the model could reflect the main stress distribution of normal human cervical spine.The model is accurate and realistic which is consistent with the biomechanical properties of the cervical spine.The model can be used to explore the biomechanical mechanism of treating cervical vertebra disease with TCTM.