Football players experience numerous blows to the head that may increase the risk for brain injury. While the majority of active football players are younger than high school age, investigations of head impact exposure (HIE) among youth players has been limited. Even less is known about the acute effects of HIE on neurological function in this population. PURPOSE: To measure HIE in youth football players over a full season and explore associations between HIE and changes in selected clinical measures of neurological function. METHODS: Twenty-two male middle school football players (11-14 yr) wore helmets outfitted with a Head Impact Telemetry System that uses six single-axis accelerometers to track and quantify head impact frequency, magnitude, duration and location. Impact data were collected for each practice and game during the season (27 practices, 9 games). Selected clinical measures of balance (BAL; AMTI force plate, NeuroCom Balance Master), oculomotor performance (OP; King-Devick Test), and simple reaction time (RT) were also assessed before (PRE) and after (POST) the season. RESULTS: The median number of head impacts per player was 252 (season), 80 (games) and 144 (practices), respectively. The maximum number of head impacts sustained by a single player was 880 for the entire season and 54 for a single session (practice). Approximately 48.8% of all head impacts had a linear acceleration between 10-20 g, 49.5% were between 21-80 g and 1.7% were greater than 80 g. Nearly all BAL, OP and RT measures were unchanged (P = 0.065 - 0.648 [BAL]; P = 0.079 - 0.221 [OP]; P = 0.346 [RT]) at POST. There were no POST deficits in any of the measures evaluated. CONCLUSIONS: This is the first study to examine associations between HIE and clinical measures of neurological function in middle school football players. Overall HIE in these players was found to be intermediate to what has been reported for younger and older (high school) players. Furthermore, these data suggest that the primary difference in HIE between middle school and high school football players is impact frequency. With no observed impairments in selected clinical measures of neurological function or a discernable relation between HIE and post-season deficits, an acute adverse effect of playing football on neurological function cannot be confirmed in this population.
Read full abstract7-days of FREE Audio papers, translation & more with Prime
7-days of FREE Prime access