Objective: The performance of five newer helmets was compared with the baseline VSR-4 helmet in 10 reconstructed cases of National Football League (NFL) collisions causing concussion. The laboratory reconstructions were conducted to determine changes in concussion risk with newer football helmets.
Methods: In 60 laboratory tests, translational and rotational head accelerations were measured in the striking and struck players represented by Hybrid III dummies. Six-axis upper neck loads and moments were measured in five cases with the struck player and five with the striking player. Biomechanical responses and concussion risks were evaluated for each collision to determine changes with newer helmet designs.
Results: Thirty-two out of 50 reconstructed cases showed greater than 10% reduction in severity index with newer helmets compared with the VSR-4; four cases increased. The average reduction in concussion risk with newer helmets was 10.8% (range, 6.9-16.7%) based on severity index. The reduction was 9.7% (range, 6.5-13.9%) based on translational acceleration and 18.9% (range, 10.6-23.4%) with rotational acceleration. Neck responses in the struck player showed a general reduction in moment and force with newer helmets.
Conclusion: With newer football helmets, there was a trend toward 10 to 20% lower risks of concussion in reconstructed National Football League game collisions. However, a few designs and cases showed increased responses. The evaluation of football helmets to the proposed National Operating Committee on Standards for Athletic Equipment concussion standard should lead to more uniform reductions in concussion risk with future football helmets.