Mild traumatic brain injury (TBI) is a common injury to service members in recent conflicts. We attempt to correlate simulation results with clinical data from advanced imaging techniques to identify TBI-related subtle alterations in brain morphology, function, and metabolism. Magnetic resonance image (MRI) data were obtained for a young adult male, after a concussive head injury caused by a road traffic accident. A similar fall of a pedestrian using an articulated human body biodynamics model was integrated with the finite element (FE) analysis using a high-resolution human head model to investigate TBI from an accident. The hyper-viscoelastic model was used to represent the strain rate dependence in brain tissues. The bone structure was simulated using an elastoplastic model to capture the focal permanent deformation. Enhanced tetrahedral elements were used in modeling nearly incompressible tissues. The localized large deformation in the head was simulated and compared with those from the MRI images. Biomechanical measures, such as stresses and strains, were correlated with postaccident medical images with respect to injury location and severity in the brain. The correspondence between model results and MRI findings shows a new way to relate computational simulation response of human head to blunt impacts with clinical data from such incidents and thus enhances our understanding of the mechanism, extent, and effects of TBI.