Correlation of an FE Model of the Human Head with Local Brain Motion-Consequences for Injury Prediction

Abstract

A parameterized, or scalable, finite element (FE) model of the human head was developed and validated against the available cadaver experiment data for three impact directions (frontal, occipital and lateral). The brain material properties were modeled using a hyperelastic and viscoelastic constitutive law. The interface between the skull and the brain was modeled in three different ways ranging from purely tied (no-slip) to sliding (free-slip). Two sliding contact definitions were compared with the tied condition. Also, three different stiffness parameters, encompassing the range of published brain tissue properties, were tested. The model using the tied contact definition correlated well with the experimental results for the coup and contrecoup pressures in a frontal impact while the sliding interface models did not. Relative motion between the skull and the brain in lowseverity impacts appears to be relatively insensitive to the contact definitions. It is shown that a range of shear stiffness properties for the brain can be used to model the pressure experiments, while relative motion is a more complex measure that is highly sensitive to the brain tissue properties. Smaller relative motion between the brain and skull results from lateral impact than from a frontal or occipital blow for both the experiments and FE simulations. The material properties of brain tissue are important to the characteristics of relative brain-skull motion. The results suggest that significantly lower values of the shear properties of the human brain than currently used in most three-dimensional (3D) FE models today are needed to predict the localized brain response of an impact to the human head. KEYWORDS-Finite element (FE) analysis; human head; brain displacement; intracranial pressure; brain material properties; brain-skull interface.

Finite-element models of the human head and their applications in forensic practice

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“…3) [23]. A simplified neck, including the extension of the brain stem to the spinal cord, dura mater, spine and muscle and skin, was also modelled.…”

Biomechanical Assessment of Brain Dynamic Responses Due to Blast Pressure Waves

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“…Similar to other components, a broad range of bulk module can be found for CSF, e.g., 0.2 MPa, 39 4.76 MPa, 40 and 2.19 GPa. 18 Table 2 presents the material properties of the head's components that have been used in the simulations.…”

Mechanical Trauma and Classification of Wounds

“…These accelerationinduced tissue strains are associated with local brain displacements within the deep white matter measured by Hardy et al (2001) and calculated by Kleiven and Hardy (2002). DAI is biomechanically characterised by a non-contact trauma caused by inertial forces as a result of abrupt cranial deceleration or sudden angular motion of the head.…”