Resolving PMHS Upper Neck Loads In High Head Angular Acceleration Testing

Initially, a series of rigid-arm pendulum tests were conducted to evaluate various methods of obtaining rotational head acceleration. Then a series of Hybrid-III dummy tests using only the head and neck system was conducted to validate the test methodology under high-rate chin loading. Finally, a preliminary series of post mortem human subject (PMHS) tests were conducted to derive the response of the human head-neck under high-rate chin loading. The results of the error analysis indicate that precision in locating the externally mounted head accelerometer instrumentation should be within 1 mm and 1 degree. Such accuracy in locating instrumentation relative to anatomical axes requires the use of a 3D positioning device such as a Faro Arm. The pyramid NAP was the best mounting device for a 3-2-2-2 accelerometer array to derive angular accelerations on the PMHS head. The head CG and mass moments of inertia should be directly measured for each preparation to obtain desired accuracy of results. PMHS testing produced upper cervical spine distraction injuries of varying severity. Occipital condyle tension load was found to be the best predictor of these injuries in the PMHS.