Epidemiology, classification, mechanism, and tolerance of human cervical spine injuries.

A review of published research is presented to examine human cervical spine injury epidemiology, classification, mechanism, and tolerance. Synthesis of the literature identifies several areas of cervical spine injury biomechanics in which the current understanding is greater than that suggested by individual investigations. Specifically, epidemiologic studies show an age dependent variation in the location of cervical spine injury. A classification scheme is developed on the basis of published work, in which the classes are defined by the resultant force acting at the site of injury. Further, for compression injuries it appears that a compression force tolerance criterion exists, and that eccentricity of the compressive force can be used to predict the type of cervical injury produced. However, to date, prediction of location of injury within the cervical spine has not been attempted. In particular, a compressive tolerance criterion is suggested between 2.75 and 3.44 kN for the adult cervical spine. In contrast, tolerance criteria for cervical injuries in other forms of loading are less well characterized. Review of the literature on spinal cord injury biomechanics and pediatric cervical spine injury reinforces the need for continued investigation in these areas.