DYNAMIC-RESPONSE OF THE HUMAN HEAD TO IMPACT BY 3-DIMENSIONAL FINITE-ELEMENT ANALYSIS

The impact response of the human head has been determined by three-dim ensional finite element modeling. This model represents the essential features of a 50th percentile human head. It includes a layered shell closely representing the cranial bones with the interior contents occu pied by an inviscid continuum to simulate the brain. A thin fluid laye r was included to represent the cerebral-spinal fluid. To validate the model, its response was obtained by applying a sine-squared pulse of 6.8 kN in magnitude and 10 ms in duration. The load was applied to a f reely supported head on the frontal bone in the midsagittal plane. The computed pressure-time histories at 5 locations within the brain mate rial compared quite favorably with previously published experimental d ata from cadaver experiments and provided a reasonable level of confid ence in the validation of the model. A parametric study was subsequent ly conducted to identify the model response when the impact site (fron tal, side, occipital) and the material properties of the head were var ied. Interestingly, the model predicted higher contre-coup pressure in the frontal lobe (from occipital impact) than that predicted in the o ccipital region from frontal impact. This finding supports clinical fi ndings of contre-coup injury being more likely to result from occipita l impact than from frontal impact.