A Peak Virtual Power Concept to Compute Brain Injuries Associated with Concussion

Concussion can result from various sports collisions and can lead to the disruption of neuronal cell membranes and axonal stretching, leading to a neuro-metabolic cascade of molecular changes in the brain. There is currently no agreement on which numerical method can assess such lowlevel injuries. This paper demonstrates for the first time that Peak Virtual Power (PVP), based on the Clausius-Duhem inequality, assuming that the injury is represented by the irreversible work in a human body, could be a candidate to capture brain distortion related to concussion. Three NFL helmet-to-helmet impacts were reconstructed with finite element analysis, using validated helmet computer models fitted with calibrated Hybrid III headforms against linear and angular acceleration impact corridors. The Hybrid III head form was then replaced with a THUMS 4.02 human head model, in which the PVP was computed at the corpus callosum and midbrain locations. The results indicate that mild and severe concussions could be prevented for lateral collisions and frontal impacts with PVP values lower than 0.928mW and 9.405mW, respectively, and no concussion would happen in the head vertical impact direction for a PVP value less than 1.184mW. This innovative method proposes a new paradigm to assess brain injuries and helmet design.