Examining the Use of Head Impact Sensors in School Sports

Head impact sensors are used to measure the g forces athletes sustain during contact in sport. Although these sensors cannot determine whether or not the athlete sustained a concussion, they serve as a promising tool for research.

Through interviews with school principals, coaches, and parents as well as focus groups with young athletes, we developed a greater understanding of the potential of head impact sensor technology to improve player safety. Key findings include the following:

• Sensors could reduce the risk of concussion. Parents reported that their children were more aware of brain injury as a result of the sensors’ presence. And students at one school reported greater awareness of their tackling technique because of concern that the sensor might record a heavy-impact reading and result in their removal from the game.
• A sound plan is necessary for implementing the sensors. Any school implementing the sensors must have a plan to manage and address logistical and troubleshooting issues as well as a plan for collecting and using the sensor data. How will the school use the data? Who will review the data? With whom will the school share the data?
• Sensors are not diagnostic tools and should not be used as such. These devices cannot determine whether athletes sustained a concussion, and there is currently no valid clinical standard for integrating these sensors with other clinical tools. However, both pilot schools used the sensors in a pseudo-diagnostic fashion. For example, one school set a threshold for mandatory evaluation of a student if an impact was recorded at 70 g and above; the other school set the threshold at 90 g and above. This confused parents and students at both schools who believed any recorded impact above these thresholds meant the student had experienced a concussion. Although it might seem logical that a higher g-force hit increases the risk of concussion, brain injury can occur even at low g-force levels.

Head Sensor Visual Project

In a separate initiative, Mathematica obtained a large de-identified data set containing head impact sensor recordings experienced by high school football players. These recordings provided the g force experienced by an athlete after an impact.

This data visualization captures the cumulative number of hits endured by a high school linebacker across all practices and games in one season. The green dots represent a low level of g-force impact, the yellow dots represent a moderate impact, and red dots represent the most severe impact. This visual helps stakeholders to understand the physical mechanism of motion and cumulative effect of hits experienced by a high school football player.