Cerebral contusions without overlying skull fracture occur primarily in the frontal and temporal lobes, and are the most frequent clinical evidence of brain damage after closed head injury. In this study, physical models of the skull-brain structure were used to estimate the intracranial strain patterns that were caused by sagittal plane inertial loading. The focus was on the changes in intracranial strains as the characteristics of the model (no slip or partial slip interface between skull and brain) and the inertial loading (direction and magnitude) were varied. The findings of these tests indicate that: (1) the skull geometry and loading kinetics contribute to the nonuniform strain patterns within a surrogate brain during dynamic loading; and (2) that the skull-brain boundary condition may play a critical role in understanding the high incidence of frontal and temporal lobe contusions observed clinically. In addition, the data may prove to be a useful guide in the development of more sophisticated techniques to estimate intracranial strains during impact. (A)
Abstract