There have been many attempts to characterize the motion of the head and neck under direct head impact or external acceleration loading. However, little information is available which describes how these motions result in deformation of the spinal cord within the spinal canal and, in turn, damage to the spinal cord.

In this study, we examined the mechanical characteristics of the head and neck structure, with special emphasis on the spinal cord, in order to gain insight into the deformation of the spinal cord during traumatic spinal cord injury. Mechanical tests of fresh human cadaver cervical and thoracic spinal cords and cervical dura mater were conducted in order to characterize the time dependent properties of these tissues. Once characterized, the results from these tests were used to evaluate appropriate materials for a surrogate spinal cord and brain. Materials deemed as suitable surrogates were used for the construction of an articulating model of the head and cervical spine. Quasistatic flexion tests of the completed physical model indicated reasonable agreement between vertebral motion and available information on the cervical spine kinematics. Additionally, motion of the spinal cord surrogate was similar to previous cadaver and human volunteer studies.

With more validation, this model may be used to measure the strains in a surrogate spinal cord during dynamic hyperflexion and hyperextension experiments. The results from these experiments, together with isolated tissue experiments conducted in parallel in our laboratory, will allow us to correlate the stretch parameters measured and the functional response of neural and vascular tissue. Relating the functional failure criteria for isolated central nervous system tissue to estimates of the spinal cord deformation, during appropriate loading conditions, will allow estimation of the spinal cord lesions expected from hyperextension, hyperflexion and subluxation of the cervical spinal column.