背景:高速公路事故逐年上升,最容易受到伤害的便是颈部.有限元分析可以很好的探究颈部损伤的力学机制.目前国内外现阶段更注重模型的优化和低速碰撞工况,少有颈部损伤和颈椎拉压应力之间关系的研究.目的:探究高速后碰撞下人体颈椎的损伤的力学机制,对颈部损伤时椎骨Von Mises应力和轴向压应力进行对比分析.方法:建立了一个包括颈椎骨、椎间盘、韧带、肌肉、小关节等组织的人体上颈椎模型.在前碰撞志愿者实验数据的基础上对模型进行了验证.运用有限元方法完成了对高速(80,120,160 km/h)后碰撞下颈椎的动力学响应.结果与结论:①经过模拟及验证表明,建立的上颈椎模型具有较高的生物仿真度,可以用于颈椎损伤研究及交通事故中各部位损伤的研究;②高速后碰撞下,速度越大,颈椎受到的损伤越严重,C1-C4中 C4的应力最大,受到的伤害最大;③用轴向压应力来判断松质骨是否发生破坏要比von-mises应力更有说服力;④在高速后碰撞下,椎骨相互之间发生错位,尤其是超出高速公路限制120 km/h后,椎骨之间错位严重,极有可能出现关节分离和骨折等情况,造成颈椎内部神经等损伤.%BACKGROUND: Highway accidents increase year by year, and the most vulnerable area is the neck. Finite element analysis can be used to study the mechanical mechanism of cervical injury. Most of researches focus on the optimization of the model and low-speed collision conditions, but the association of neck injury with cervical tension stress is little reported. OBJECTIVE: To explore the mechanical mechanism of neck injuries caused by traffic accidents, and to compare the von Mises and axial stress of the cervical vertebrae. METHODS: A cervical spine model including cervical vertebrae, intervertebral disc, ligament, muscle, facet joint was set up. The model was validated based on the experimental data of the former impact volunteers. The dynamic response of the cervical vertebrae was achieved using the finite element method (80, 120, and 160 km/h). RESULTS AND CONCLUSION: (1) The established upper cervical model had a high biosimulation, which could be used in studies on the cervical injury and each part injury caused by traffic accidents. (2) Under high-speed post-impact condition, the cervical injury became severe with speed increasing, especially C4level. (3) The axial stress was more available to assess the injury of cancellous bone than von Mises. (4) After high-speed post-impact, the vertebrae diaplaced, especially at 120 km/h, thereby causing articular separation and fracture, further inducing nerve root injury.
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