Who Are the Authors of the Study?
Eamon T. Campolettano and Steven Rowson
Why Was This Study Done?
At the time of this study, NOCSAE’s ND006 youth football helmet standard was in Proposed status. Because this standard was being developed to help address the unique injury environment of youth players, NOCSAE requested research to evaluate impact-testing criteria in the standard.
What Was the Purpose of This Study?
The primary goal of this study was to compare laboratory impacts to real-world head impacts sustained by youth football players during games and practices. Researchers wanted to find out if the laboratory tests defined by the proposed standard accurately simulated the severity and types of impacts that occur in actual youth football gameplay.
When Did This Study Take Place?
The on-field head impact data used in this study were collected over four football seasons, spanning from 2015 to 2018.
How Was the Study Done?
To gather data on real-world head impacts, the researchers equipped 112 youth football players (aged 9–14) with helmets containing accelerometer arrays. Accelerometers are small devices that measure acceleration, allowing the researchers to record the severity of head impacts during play.
Next, the researchers conducted laboratory impact tests for comparison to the on-field impacts. These tests were performed on two different helmet models at four specific impact locations, as defined in the proposed standard. The Severity Index (SI) and peak rotational head acceleration were calculated for each impact, providing key metrics for comparison with the on-field data.
To analyze the relationship between the laboratory and on-field impacts, the researchers used a bivariate cumulative distribution function (CDF), a statistical tool that allows for the comparison of two variables simultaneously. In this case, the SI and peak rotational acceleration values from the laboratory tests were compared to the distribution of these values in the on-field data.
What Were the Results of the Study?
The results of the study showed that the laboratory impact tests consistently produced SI and peak rotational acceleration values that were among the top 10% of the most severe impacts experienced by the youth football players on the field. This indicates that the proposed NOCSAE youth standard is focused on the most severe impacts that are likely to occur in youth football. However, the study also found that the laboratory impacts were generally more severe than the average biomechanics associated with concussions that were actually observed in the on-field data.
What Are the Implications of This Study?
This study has important implications for the development of NOCSAE’s youth football helmet standard. The findings suggest that while the proposed standard assesses high-severity impacts, it may be too stringent, as the laboratory tests produced impacts that were more severe than those typically associated with concussions in young players. This raises the question of whether the standard’s biomechanical limits for SI and peak rotational acceleration should be adjusted to better reflect the actual conditions that lead to concussions in youth football. The study highlights the need for continued research in this area, particularly to gain a more detailed understanding of the biomechanics of concussion in youth athletes.
TERMS
Severity Index (SI): A measure of the severity of a head impact, taking into account both the magnitude and duration of the acceleration.
Rotational Head Acceleration: A measure of how fast the head rotates during an impact, which is thought to be a key factor in concussions.
Biomechanical: How forces and movement affect the human body.
