Comparison of video-based and sensor-based head impact exposure.

Area of Science:

• Biomechanics
• Sports Science
• Injury Prevention

Background:

• Wearable kinematic sensors are used to quantify head impact exposure.
• Existing sensors often lack accuracy in estimating impact kinematics and count.
• Independent methods are needed for validating sensor-based impact data.

Purpose of the Study:

• To compare head impact quantification between instrumented mouthguards and video analysis in collegiate American football.
• To evaluate the accuracy of sensor-based impact location detection.
• To develop and validate a novel exposure metric accounting for player participation.

Main Methods:

• Seven collegiate American football players were equipped with instrumented mouthguards.
• Video recordings of practices and games were used for comparison.
• Impacts were analyzed using both sensor data and video observation, with a focus on location and timing.

Main Results:

• Instrumented mouthguards recorded significantly more impacts (2,032) than identified in video (271).
• Matched video and sensor data yielded 193 and 217 impacts, respectively.
• Impact location distributions were similar between methods, but sensor accuracy for location prediction was limited (81/217).
• A new metric, impacts per player-play, showed higher exposure during games (0.35) than practices (0.20).
• Traditional impacts per player-hour metric showed higher exposure during practices (4.7) than games (3.7).

Conclusions:

• Instrumented mouthguards and video analysis provide complementary data for head impact assessment.
• A novel player-play metric offers a more accurate representation of head impact exposure by accounting for participation.
• Further research is needed to refine sensor accuracy and validate exposure metrics across different sports.