Investigation of Brain Injury Kinematics: Introduction of a New Technique

Abstract The principal focus of this study is the measurement of relative brain motion with respect to the skull and between different regions of the brain. Using a high-speed bi-planer x-ray system and reduced density targets (RDT’s), the strain in a relatively small volume of brain can be determined. Relative motion between the brain and skull can be determined using implanted triaxial neutral density accelerometers (NDA-3’s) and a rigid-body accelerometer array (3-2-2-2) mounted to the apex of the skull. A suspension fixture is used for inverted, isolated-head testing. Two occipital impacts, 2.7 m/s and 4.2 m/s, are conducted on a single specimen. The high-speed x-ray system provides validation of the NDA-3 performance, and allows tracking of the RDT locations. Relative displacements between the brain and skull are found to be on the order of 3–5 mm, and stretch levels within the RDT array reach approximately 9 percent. These initial results provide the opportunity to introduce the new technologies and techniques designed for use in this ongoing study.