Avenues for Sport-Related Concussion Prevention in High School Football: Effect of Limiting Collision Practices

Abstract

Context Football continues to demonstrate the highest rate of sport-related concussion (SRC) in high school athletics. To mitigate the SRC risk, the Michigan High School Athletic Association (MHSAA) implemented rules aimed at reducing the number of collisions occurring in practices. Objective To estimate the rates of SRC in MHSAA football programs and evaluate progressive limitations to collision practices over 5 consecutive seasons. Design Retrospective cohort study. Setting Michigan high school football. Patients or Other Participants High school (9th–12th grade) football athletes (>99% male) participating in MHSAA-sanctioned events. Main Outcome Measure(s) Designated administrators at each school recorded the total number of participating athletes and SRCs (defined as head injuries resulting from athletic participation that required the student-athletes to be withheld from activity after exhibiting signs, symptoms, or behaviors consistent with an SRC) in the MHSAA injury-surveillance system each season (2015–2016 through 2019–2020). Progressive limitations to collision practices occurred across the study period. We estimated athlete-exposures (AEs) as the total number of players multiplied by the total number of possible practices (11 weeks, 4 days each) or competitions (9 weeks, 1 day each) during each season. Incidence rates and rate ratios (RRs) with 95% CIs were used to compare practice and competition SRCs and each season with the most recent season. Results A total of 7755 football SRCs were diagnosed across the 5-year period. The overall SRC rate was 8.03 per 10 000 AEs (95% CI = 7.85, 8.21). The competition SRC rate (30.13/10 000 AEs) was higher than the practice rate (3.51/10 000 AEs; RR = 8.58; 95% CI = 8.19, 9.00). The practice SRC rate was lower in 2017–2018 (RR = 0.86; 95% CI = 0.77, 0.97), 2018–2019 (RR = 0.89; 95% CI = 0.79, 1.0), and 2019–2020 (RR = 0.83; 95% CI = 0.74, 0.94) relative to 2015–2016. Conclusions We found that the progressive limitations to collision practices were protective against SRCs, as the rate of SRC was lower in the 3 most recent seasons relative to 2015–2016.

Publicly available data sources in sport-related concussion research: a caution for missing data

“…American football offers several examples. For example, injury surveillance research identified the protective impact of progressive limitations to collision practices (Bretzin et al 2022 ; Pfaller et al 2019 ; Broglio et al 2016 ). Other research using injury surveillance found that rule changes, including the Ivy League Kickoff Rule (Wiebe et al 2018 ) and penalizing targeting (Baker et al 2021 , 2022 ) were associated with reduced rates SRC, albeit sometimes with unintended consequences (e.g., increasing likelihood of lower extremity injury) (Hanson et al 2017 ; Westermann et al 2016 ).…”

Prevention strategies and modifiable risk factors for sport-related concussions and head impacts: a systematic review and meta-analysis

“…Restricting the frequency and/or duration of collision practices in adolescents reduced head contact and practice-related concussion rates. [89][90][91][92] Similar policy changes have not been successful at the collegiate level (supplemental). [93][94][95] A MA combining studies indicated a 64% reduction in practice-related concussion rates when policy and non-policy approaches to limiting contact in practices were implemented across adolescent and adult leagues (IRR=0.36;95%CI:0.16-0.80) (Figure 5).…”

“…75,76,[78][79][80] Policy limiting the number and duration of contact practices in American football has led to reduced SRC and head impact rates in adolescents. [89][90][91][92] Limiting the number of contact practices did not have as much success in terms of reducing SRC risk or head impacts at the collegiate level as teams were noted to run longer duration practices and with more intense contact (supplemental). [93][94][95] Further restrictions on limiting practice duration may help in decreasing head impacts and SRC risk at the collegiate level.…”

The National Football League Concussion Protocol: A Review

“…Similar to rule changes implemented in the NFL, leagues may also consider implementing their own data-driven rule changes to mitigate concussion risk based on their own unique observations and needs. At the league and team levels, decisions to limit or eliminate contact in practice can be considered, as this approach has been shown to decrease concussion incidence in the Ivy League [ 3 ].…”