The mechanisms of injury of the human neck are potentially related to the forces and bending moments acting on the spinal column. An injury criterion that combines the effects of the time history of force and moment, N(sub ij), has been adopted by the USA federal government for vehicle crash regulations. This paper presents two analytical approaches to evaluate the N(sub ij) injury criterion using previously published biomechanical data: a direct fit optimization analysis and a statistical analysis. The results show that no values used in the N(sub ij) criterion corresponding to compressive force, extension moment and flexion moment will optimally separate the injury and non-injury cases in the biomechanical data set. Only the tensile force allows identification of the injury risk. All indications are that increasing the weight given to moment decreases the accuracy of the prediction. (Author/publisher).
Abstract