Teaching tool
A number of top concussion researchers also believe that real-time monitoring of impacts could help reduce the total amount of brain trauma from repeated subconcussive blows by identifying athletes sustaining a large number of such hits due to improper blocking or tackling technique. In a recent article on SI.com, Kevin Guskiewicz, PhD, ATC, Kenan Distinguished Professor and Director of the Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center at The University of North Carolina at Chapel Hill, pointed to a third practical use for impact sensors outside of the research arena: to help coaches and other personnel identify athletes who are sustaining a high number of high force impacts, especially to the top front of their helmets that appear to be the most worrisome from a brain trauma standpoint, as a result of poor tackling or blocking technique. "If a player is observed repeatedly sustaining larger impacts to the crown of his head," he told SI, "coaches will work with him on adjusting his technique," said Guskiewicz.
Using impact sensors as a teaching tool isn't just happening at the college level. It is happening in high school football, too. After Purdue researchers[16] found that high school football linemen who sustained a high number of high impact sub-concussive hits over the course of a season were the ones suffering impairment of their visual memory, the information led at least one player to change his blocking technique.
Tom Talavage, the lead author of the Purdue study, told PBS's Frontline in a 2011 interview, that he thought that at least 50 percent of the high impact hits linemen and linebackers were sustaining were due to poor technique. "Some of the players that we have on our team [do] have not very good technique, to be quite honest. And what you'll find is, they will launch into a play, and they will lead with their helmet. Other players will more correctly keep their head up, try to get their arms up as a blocking technique, or when they're rushing, they will try to get their arms up as a means to push the offensive lineman out of the way. Those technique differences lead to a very large difference in the total number of blows experienced and where those blows are experienced on the head."
Talavage said that, when one of the offensive lineman who was found to have been functionally impaired after sustaining a high number of subconcussive blows - impairment which persisted beyond the season - decided to change his technique, he experienced a drastic reduction in the number of blows he sustained to the top front of his head and a moderate reduction in the total number of helmet hits.
The result was that, after the second season, "his neurocognitive testing never detected any deficits, and from an imaging perspective we saw substantially less change in his fMRI activity. There's still some, because he's still getting hit, but his technique changed the distribution."
Research suggests that the cumulative effect of subconcussive impacts may increase the risk of long-term neurodegenerative diseases such as CTE, PD, AD, MCI and ALS. While researchers continue to look for the concussion "holy grail" in the form of specific impact thresholds above which concussions are highly likely and/or the number of impacts or the magnitude of impacts per week or per season that substantially increase the risk of long term brain injury, impact sensor technology is available right now to do what we can to reduce total brain trauma by using impact data to identify kids who need more coaching so they can learn how to tackle and block without using their helmets.
Dissenting view
Not surprisingly, some concussion scientists and researchers take a more cautious approach to the use of impact sensors. Despite finding that underreporting continues to be what she wrote in two 2013 studies to be an "alarming" [14] and "overwhelming" problem, [10] Johna Register-Mihalik, told MomsTEAM that the the reason the use of impact sensors was not among the recommendations she and her co-authors made to address the problem was that she viewed "the use of impact sensors in concussion detection, as the science, although a growing field of information, is just not quite there in how these may best be used from a clinical standpoint and across all sport settings."
"As it stands, there is no absolute threshold for concussive injury and while these sensors may identify individuals who receive a certain type of hit or impact, we do not yet know if those impacts not identified by a set threshold may lead to concussion. In many ways, this may provide a false sense of security, in that 'if the sensor didn't go off, I must not have a concussion.'"
Register-Mihalik recognized that "there is certainly potential for this type of technology to have great implications in the identification of concussion as the science advances," but, she argued, "we need more scientific and unbiased evidence of their ability to detect concussion before they are widely used and recommended in all settings. Until that time, there are some good examples of identification techniques of having trained observers, a parent advocate and continuing to promote concussion education that we know will increase identification rates."
Editor's Note: two real-time impact monitoring systems, Impakt Protective's Shockbox and i1 Biometrics' Hammerhead (now called Vector) impact sensing mouthguard, are featured in MomsTEAM's 2013 PBS documentary of concussions in high school football, "The Smartest Team: Making High School Football Safer." As of June 2015 MomsTEAM/SmartTeams has field tested seven brands over four years with football players ages 5-17.
For a guide to selected impact sensor products, click here.
For answers to frequently asked questions about impact sensors, click here.
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