ABSTRACT
Objective To establish the precise finite element model of the head and neck based on human anatomical structure, so as to study neck injuries caused by rear impact at different speeds. Methods The model was based on CT scan images of the head and neck of human body. The Mimics software was used to reconstruct the three-dimensional (3D) bone, and the 3D solid ligaments, small joints and other tissues of the neck were improved and meshed by HyperMesh. The generated models included the head, 8 vertebrae (C1-T1), 6 intervertebral discs (annulus, nucleus pulposus and upper and lower cartilage endplates), facet joints (cartilage and joint capsule ligaments), ligaments, muscles, etc. Finally, the model verification and post-collision calculation were completed in the finite element post-processing software. Results The simulation results of the models under axial impact, front and back flexion and lateral flexion were compared with the experimental data to verify the effectiveness of the model. Then post-collision simulation at the speed of 20, 40, 60 and 80 km/h was conducted. At the speed of 20 km/h, there was no damage to the neck. At the speed of 40, 60 and 80 km/h, the ligament was the first to be damaged. As the speed increased, the stress on tissues of the neck increased continuously. At the speed of 80 km/h, the maximum stresses of the dense bone, cancellous bone and annulus of the cervical vertebrae were 226.4, 11.5, and 162.8 MPa, respectively. When the ligament strain reached the limit, tearing began to occur. Conclusions The finite element model of the head and neck established in this study has high bionics and effectiveness, and can be used for studying neck injury analysis in traffic accidents, which is helpful for the diagnosis, treatment and prevention of cervical spine injury to a certain extent.