Influence of head mass on temporo-parietal skull impact using finite element modeling.

The effect of head mass on its biomechanical response during lateral impact to the head is investigated in this computational study. The mass of the head of a state-of-the-art validated finite element head model is altered by ± 10 % from the base value of 4.7 kg. Numerical simulations of lateral head impacts for 30 cases (representing 15 human cadaver experiments × 2 mass configurations) are performed using the LS-DYNA solver at different velocities ranging from 2.4 to 6.5 m/s and three impacting conditions representing different stiffness and shapes of the contact/impact surfaces. Results are compared with the original model using the baseline head mass, thus resulting in a total of 45 simulations. Present findings show that the head mass has greater influence for peak interaction forces and the force has a greater dependency on stiffness of contact surface than the shape. Mass variations have also influence on skull strain energy. Regardless of increase/decrease in skull strain energy influenced by head mass variations used in the computational study, the 50 % fracture tolerance limit was unaltered, which was 544 mJ. The present study gives a better understanding of the mechanism of temporo-parietal skull impact.