Effect of infraction type on head impact severity in youth ice hockey.

PURPOSE To identify the effects of infractions sustained during participation in youth ice hockey on biomechanical measures of head impact severity. METHODS Sixteen adolescent Bantam-aged male ice hockey players (age = 14.0 +/- 0.5 yr, height = 171.3 +/- 4.5 cm, mass = 63.7 +/- 6.6 kg) were equipped with accelerometer-instrumented helmets to collect biomechanical measures relating to head impacts (linear acceleration, rotational acceleration, and Head Impact Technology severity profile (HITsp)) sustained while participating in ice hockey. Single-camera video footage from 54 games was synchronized with the head impact data, and all viewable collisions (n = 665) were evaluated as resulting from a legal collision or an infraction. Infractions were further categorized into boarding or charging, checking from behind, and elbowing or intentional head contact. Statistical analyses included random-intercepts general linear mixed models. RESULTS Infractions were observed in 17.3% (115/665) of all body collisions. Overall, collisions involving infractions had higher linear accelerations (P = 0.012) and HITsp (P = 0.021) than collisions with no infraction. Specifically, elbowing, head contact, and high sticking infractions resulted in greater linear acceleration (P = 0.005) and HITsp (P = 0.010) than collisions with no infraction. A strong trend for higher rotational accelerations in this infraction type compared with legal collisions was also present (P = 0.059). CONCLUSIONS Infractions result in higher measures of head impact severity than noninfraction collisions. Athletes and coaches should conform to playing rules, and officials should enforce more stringently existing rules and assess more severe penalties to participants who purposefully attempt to foul an opponent at the youth ice hockey level.