A computational head-neck model was developed to more efficiently study dynamic head and neck responses to near-vertex head impact. This model consisted of rigid vertebrae interconnected by assemblies of nonlinear springs and dashpots, and a finite element (FE) shell model of the skull. Quasi-static flexion-extension characteristics of ten human cadaveric cervical spines were measured using a test frame capable of applying pure moments. Computational model parameters were based upon these measurements and existing literature data. The model reproduced the shape and timing of the cervical spine buckling deformations observed in high speed video of cadaveric studies of near-vertex head impact. Head and neck force histories and head acceleration histories agreed with those reported in cadaveric studies.A sensitivity analysis of the model parameters revealed that head and neck responses were most sensitive to changes in head stiffness, head mass, and flexion-extension properties. This suggests that an appropriately configured deformable head and accurate experimental characterization of motion segment flexion-extension behaviour are critical to reliable model predictions. The validated, computationally efficient model is well suited for large-scale parametric studies of the role of impact surface properties on injury risk. It also serves as a foundation for future model enhancements such as the incorporation of the cervical musculature. (A)
Abstract