Incidence and magnitude of head impacts experienced by male adolescent rugby players: A two-season comparison

Abstract

Introduction. In recent years there has been an increase in public and media awareness regarding the safety and brain health of players either after a concussion or after long-term participation in rugby union. Because of the nature of rugby, players are exposed to repeated collisions which may or may not result in a concussion. These impacts involve both linear and rotational acceleration. At present there is sparse research investigating the role of collisions in rugby on the brain health of junior rugby players. Methods. Forty U16 male rugby players aged 14-16 years completed pre-season and post-season assessment which included: (i) advanced magnetic resonance imaging (MRI) of the brain, (ii) neurocognitive testing, (iii) health history questionnaire, (iv) motor control questionnaire. Participants wore instrumented mouthguards during their club and school season (recording collisions 8g and above) for all games and contact trainings. The collisions were video verified and coded according to relevant descriptors. Results. Magnitude and incidence data for the male cohort, across two seasons, can be presented at this time. Average total incidence per team was 14.19-16.25 impacts at training and 71.95-105.4 impacts at games. Incidence range per player was 12 to 496 impacts experienced per season, with an average of 107.61. Average peak linear acceleration (PLA) was 18.15-19.17 at training and 20.08-20.63 at games. Magnitude range per player was 13.8-28.2 g, with an average of 19.48. Player loading influenced incidence rate and maximum PLA, but not average PLA. Wider study results, expected in early 2024, will incorporate results from neuro-cognitive testing, motor control questionnaires, and MRI scans. Conclusions. The study highlights the need for objective data to measure head impact exposure in rugby union, especially at the junior level. Monitoring head impact loading is crucial for rugby safety and may help to establish a distinction between kinematics of concussive and non-concussive injury.