Development and application of a method to simulate commotio cordis inducing impacts for the evaluation of football chest protective equipment

Abstract

As one of the most widely played and watched contact sports in the United States, football presents a significant risk of blunt chest trauma. Thus, effective chest protection is essential to prevent rare but fatal injuries like commotio cordis. Despite the risk of fatal outcomes, current test methods for certifying chest protective equipment fail to account for injury metrics relevant to commotio cordis and neglect body-to-body collisions, common in contact sports such as football. This study presents the development of a method that simulates shoulder-to-chest impacts via a pneumatic linear impactor, and the evaluation of football chest protectors, with the goal of informing cardiac safety. This statistically verified method considers two impact locations vulnerable to commotio cordis at minimum and moderate football tackle testing speeds to evaluate chest forces, rib deflections, and viscous criterion values of seven different football chest protector combinations on a Hybrid III Upper Torso Assembly. Additionally, this study investigates the quasi-static behavior of the chest to evaluate the predictive capability of quasi-static tests for the dynamic performance of these protector combinations. Researchers show that current football chest protectors fail to reduce viscous criterion values below the established 25% risk threshold for commotio cordis risk at moderate football tackle testing speeds. Additionally, researchers observed a moderate trend between quasi-static stiffness and dynamic viscous criterion ( $R^2$  = 0.580, p = 0.0468, slope = 0.059, 95% CI [0.02, 0.963]). Ultimately, a statistically verified test method was developed that differentiates between protector combinations, locations, and speeds, to inform certification standards for football chest protective equipment.