Playing Rule Article Eight Decreases The Rate Of Sport Related Concussion In Nfl Players Over Two Seasons

ObjectivesThe objectives of this study were to determine if rule article 8 significantly reduced (1) the rate of concussions sustained by NFL players during regular season games, (2) the average games missed secondary to concussion injury, and (3) the number of players placed on the injury reserve for sport-related concussions (SRC).MethodsThis study was a retrospective review of all NFL players who were placed on the publically available injury reports for a concussion from the 2016-2017 to 2019-2020 regular seasons. Player's date of injury was cross-referenced with an absence of statistics from the respective games for which they were ruled out to ensure accuracy. With article 8 taking effect starting with the 2018-2019 season, players were assigned to a pre- or postrule cohort based on date of injury for purposes of injury rate comparison. Injury rates were calculated per 1000 athletic exposures (AE). Relative risk (RR) with 95% confidence intervals (CI) compared injury rates between the two cohorts. Average number of games missed and number of players placed on injury reserve (IR) per year were also calculated. Continuous variables were statistically compared using two-tailed t-test, while categorical variables were compared using Chi-squared test. Statistical significance was set at P <= 0.05.ResultsThere was a 40% decrease in the SRC rate when comparing the post- to the pre-article-8 cohort (3.3 vs 5.5/1000 AEs, respectively; RR 0.60; 95% CI 0.50-0.73). There was no significant difference in average games missed per concussion or percentage of players placed on the IR due to SRC between the two cohorts.ConclusionsThe rate of SRC over the past two NFL seasons following the enactment of playing rule article 8 has significantly decreased when compared with the two seasons prior. The average games missed per concussion and the number of players placed on the IR due to SRC has not significantly changed under playing rule article 8.