FE ANLYSIS OF HUMAN NECK DYNAMIC RESPONSES UNDER REAR-END IMPACT

A detailed three-dimensional finite element model of Chinese human neck developed previously is improved and used to investigate the dynamic responses under rear-end impact. The model is composed of the seven cervical vertebrae (C1-T1), the first thoracic vertebra (T1), the intervertebral discs (nucleus, annulus, endplates), ligaments and muscles. It includes eight-node solid elements, hughes-liu beam elements and two-node cable elements. The material properties are characterized by isotropic, viscoelastic and cable. The volunteer experimental data during rear-end impact is applied to the finite element model to obtain segmental rotational angle and von mises stress of soft tissues. The cervical S-shaped curve and C-shaped curve are predicted. Each level of soft tissues experiences the greatest stress at the time of maximum cervical S-shaped curve and C-shaped curve. The highest segmental angle and maximum stress mainly occur at C7-T1.The cervical spine is likely at the risk of hyperextension injuries during rear-end impact. The simulation of finite element models is helpful for the understanding of spinal kinematics and mechanisms of spinal injury.