Modal analysis of a human head model with finite element method

Abstract

Cerebral concussion caused by a contact in American football games is a serious problem today, since its mechanism remains unclear so far. From some prior researches head vibration would induce the cerebral concussion. In this study we had carried out a modal analysis for a human head model consisting of skull, falx cerebri, cerebellar tentorium, cerebrum, cerebral cortex, corpus callosum, cerebellum, brainstem, septum pellucidum, cervical cord, cervical vertebrae, and lateral ventricles (cerebrospinal fluid) with mechanical properties that we referred to some papers. The results show that the 1st, the 2nd and the 3rd modes are sagittal rotation (eigenfrequency: 7.29 Hz), coronal rotation (eigenfrequency: 7.65 Hz), and axial rotation (eigenfrequency: 11.24 Hz), respectively. The maximum of 1st principal stress, 3rd principal stress, equivalent stress and 1st shear stress for these three modes were located in the cervical cord, cervical vertebrae and skull, not inside the brain. On the other hand, the maximum and minimum principal strain were located inside the brain for these three modes. Nucleating higher strain inside the brain might be caused to occur cerebral concussion when the head vibrated due to the contact.