Role of impact location in concussion outcomes among US high school football players

Background: Research has examined concussion events by impact location (i.e., the area on the head in which impact occurs). However, little research exists regarding impact location's association with concussion-related outcomes, such as symptomatology, symptom resolution time, and length of time until return to play. Methods: National High School Sports-Related Injury Surveillance Study data (2008/09 to 2011/12) were analyzed to calculate rates and describe circumstances of football concussion by impact location (i.e., front-, back-, side-, and top-of-the-head). Results: The concussion rate was 5.1 per 100,000 athlete exposures (AEs) (95% Confidence Interval [CI]: 4.8, 5.4), with most concussions occurring from front-of-the-head impacts (57.1%) followed by side-of-the-head (27.9%), back-of-the-head (7.5%), and top-of-the-head impacts (7.4%). Most concussions were caused by head-to-head contact (70.0%), followed by contact with another body site (e.g., elbow, knee) (23.9%), and contact with playing surface (following player-player contact) (6.1%). The number of symptoms reported, symptom resolution time, and length of time to return to play were not associated with impact location. However, a higher proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.8%) than those sustaining concussions from impacts to other areas of the head (3.3%) (IPR [Injury Proportion Ratio]: 2.7; 95% CI: 1.4, 5.4; P=0.01). Conclusion: These findings support calls for better enforcement of rules prohibiting players from initiating contact with the top of the head and better education of players regarding proper tackling technique.