Injuries to the head-neck system of drivers and passengers in car accidents have been a major cause of permanent disabilities or even death. Rear-end automobile impacts cause whiplash injuries the majority of which can recover in a short time. Yet, the injuries in some rear-end crashes cause long-term health issues and disabilities. Therefore, the whiplash injury mechanisms that cause injuries to the head and the neck, are tried to be explained and simulated using mathematical models of the head and the neck. In this study, a two dimensional physical model which is composed of a head, seven cervical vertebrae and a mass representing below the T1 vertebrae, is presented for human head and neck system. The model with 24 degrees of freedom is considered as concentrated masses, which represent the different body segments, interconnected by springs and dampers. The head and vertebrae are modelled as rigid bodies and soft tissues (intervertebral discs, facet joint, ligament and muscles) are modelled with conventional mechanical joint as massless springs and damper elements. Moreover, inertial properties, masses of the human cervical spine vertebrae and initial neck curvature are taken from literature. Spring and damping coefficients for soft tissues are nonlinear and thus, soft tissue behaviour was reflected to the head-neck system. Lagrange method is used for deriving the mathematical model of the human cervical spine. Then, simulation results are presented to assessment of whiplash injury mechanism and development of injury prevention systems.
Anahtar Kelimeler: neck model, modelling and simulation, whiplash, rear impact
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