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Parametric study of impact parameters on peak head acceleration and strain for collision impacts in sport

Abstract Collisions are a common cause of concussions. The nature of a collision impact is governed by the velocity of the striking players and the body parts involved. The purpose of this study was to describe the effects of velocity, mass, surface stiffness and location on peak linear and angular acceleration and strain. A variable-mass pendulum fitted with simplified impact surfaces representing the stiffness of an unprotected head, a protected (helmet) and a well-padded (i.e. shoulder pad) condition were used to impact a Hybrid III headform at four locations and velocities. Headform accelerations were input into a finite-element model to approximate peak strain in the cerebrum. Stiffness was most influential on peak linear and angular acceleration, and strain was most influenced by velocity. Interaction effects demonstrated that the 9 kg mass had consistently higher peak linear and angular acceleration and strain than the 15 kg mass between 3.0 and 4.5 m/s. Mass and velocity interactions may have important implications for age and size related concussion risk.