Athletes have another reason to smile: Sensor-laden mouth guards provide vital head trauma statistics

Head trauma in contact sports is not a new phenomenon, but it has only recently become a national concern. Concussions suffered during sports, especially repeated injuries, correlate with long-term cognitive problems, mental health issues and dementia. Correct diagnosis and treatment of concussions relies on identifying problematic head impact and understanding the biomechanics of sports-related head trauma.

While reconstruction of accidents from videos provides valuable information about the type of injuries that contact athletes face, detecting injuries needing immediate attention requires real-time information of head impact. X2 impact uses sensors in mouth guards to provide information about the linear and rotational accelerations of impact occurring during sports collisions. The data transmitted to monitors or smart phones on the field provides coaches and athletic trainers real-time information about head impact. 

Concussions occur after traumatic injury to the head and brain. These injuries affect a variety of brain functions and can range from mild to fatal. Repeated trauma to the head, which may occur in sports, can result in chronic traumatic encephalopathy (CTE). CTE is a neurodegenerative disease caused by repeated head trauma. The symptoms begin to occur around midlife and include mental health changes, cognitive disfunctions, and memory problems. Although first noted in boxers, susceptibility for acquiring this disease extends to anyone exposed to repeated mild head trauma. Currently, definitive diagnosis of CTE only occurs postmortem, but imaging techniques may detect biomarkers of this disorder in living patients.

Understanding the long-term effects of repeated head trauma on future brain function is not lost on players currently suffering from loss of brain function. The last note of Dave Duerson, a former defensive back from the Chicago Bears, read, “please see that my brain is given to the NFL’s brain bank”. In shooting himself in the chest he left his brain intact. Tragedies such as this only highlight what has long been known, that repeated head trauma causes neurological problems that extend beyond the initial injury.

The acknowledgment that concussions need immediate attention has led to changes in guidelines. From professional sports leagues, such as the National Football League (NFL) and National Hockey League (NHL), to high schol sports, policies are being put in place that require the assessment of head injuries before players are allowed to reenter the game. Although these guidelines are a first step, the current protocols for assessment of injuries may not be enough. A real-time measure of force to the head could provide a more objective approach to identifying potentially problematic head impact.

Helmets equipped with inertial sensors and gyros are used in football to provide information about impact force to the head and the subsequent effect on the brain. These helmets, however, are quite expensive. Mouth guards with sensors may provide a cheaper alternative. Six acceleration and rotation sensors in the X2 impact mouth guard record the gravitational force of impact and send this information to the X2 access point on the sideline. An algorithm estimates the impact that the brain experienced and transmits the information to authorized mobile phones. This provides real-time impact reports to the sidelines. This information provides objective measures of impact, which is essential in sports that have traditionally followed a “shake it off” approach. Patents are pending on this technology.

Currently, the mouth guards are being tested at select colleges, such as Stanford and University of Washington, and market launch is expected early 2012. The co-director of the Center for the Study of Traumatic Encephalopathy, Robert Cantu, however, remains skeptical about the extent of the information that is provided by sensor based measures of impact.

Although sensor-based measures of head impact provide real-time information about hits, they may not adequately assess the effects of various impacts on the brain. Since symptoms of CTE don’t arise until years after the injury, it is unclear how much trauma and what type of trauma leads to this type of disorder. Despite these limitations, real-time information provides alerts about potential problems. Furthermore, long-term data collection from these devices can further our understanding of the long-term consequences of repeated head trauma.

Recent focus on the long-term negative effects of head trauma, especially repeated head trauma, occurring during contact sports is resulting in new guidelines to protect players. These guidelines might be hard to enforce, as underreporting of symptoms is common in sports.

Although X2 impact will not prevent concussions, it will provide real-time information about head impact. Understanding the true impact on the brain in real time will provide early detection of concussions and subsequent early treatment, which will hopefully minimize the long-term consequences of the injury. Furthermore, data collected from these devices will further our understanding of which hits are most damaging for brain function.