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Updated: Nov 10, 2025

Modified Drop Tower Impact Tests for American Football Helmets
Published on: February 19, 2017
Player age and initial helmet contact among American football players
David X Wang1, Anthony M Napoli2, Alex R Webb3
1Allegheny Health Network, Department of Orthopedics, Pittsburgh, PA.
Objective:
Concussions and chronic traumatic encephalopathy (CTE) related to professional football has received much attention within emergency care and sports medicine. Research suggests that some of this may be due to a greater likelihood of initial helmet contact (IHC), however this association has not been studied across all age groups. This study aims to investigate the association between player age and IHC in American football.
Methods:
Retrospective review of championship games between 2016 and 2018 at 6 levels of amateur tackle football as well as the National Football League (NFL). Trained raters classified plays as IHC using pre-specified criteria. A priori power analysis established the requisite impacts needed to establish non-inferiority of the incidence rate of IHC across the levels of play.
Results:
Thirty-seven games representing 2912 hits were rated. The overall incidence of IHC was 16% across all groups, ranging from 12.6% to 18.9%. All but 2 of the non-NFL divisions had a statistically reduced risk of IHC when compared with the NFL, with relative risk ratios ranging from 0.55-0.92. IHC initiated by defensive participants were twice as high as offensive participants (RR 2.04, p < 0.01) while 6% [95% CI 5.4-7.2] of all hits were helmet-on-helmet contact.
Conclusions:
There is a high rate of IHC with a lower relative risk of IHC at most levels of play compared to the NFL. Further research is necessary to determine the impact of IHC; the high rates across all age groups suggests an important role for education and prevention.
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