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Soccer’s new secret weapon for head-impact safety? The X2 Patch may be it


Just a piece of white tape placed discreetly behind the ear.

While there’s plenty of work still to be done, this inconspicuous new gadget has the chance to change the landscape of soccer safety as we know it.

The first hint the X2 patch would have an impact was when it was used on rugby players in England. Soccer would be smart to pay heed to the results.

The 2014 World Cup illustrated the serious problem currently facing the sport. Just ask Alvaro Pereira…well, don’t ask him, because he probably wouldn’t admit it. Pereira was rendered blatantly unconscious on the pitch in Brazil by Raheem Sterling’s knee, but managed to override the physio, allowing Pereira continue. The examples continued through the subsequent Premier League season, with Hugo Lloris and Romelu Lukaku making headlines following their inability to remember significant events after serious blows to the noggin.

But players have been getting rocked in the head as long as the game has been around. We see the worst blows on highlight recaps, but there are thousands of impacts nobody sees.

Only now are we beginning to understand just how impactful those headshots are to the future of players.

This brings us to Allianz Park in London, England. Jan. 3, 2015. What the heck is that white piece of tape behind the Saracens players’ ears?

“The crucial question is: ‘What are the medium to long-term effects of repeated concussion on a professional rugby player?’” That’s what Saracens chief executive Edward Griffiths wants to know. “Blows to the head are sort of a reality of the game, but there’s too many questions and not enough answers. We have various protocols to determine when a player should leave the field after being struck on the head, and [to determine] when he’s fit to play again after being concussed. But we are not satisfied that any of those protocols are based on real medical evidence.”


Saracens player Richard Wigglesworth wearing the X2 Patch behind his ear.

So he set off to find out on his own.

“We did a lot of research, this program has been eight months in research, and we came down to two companies, one in Australia and one in Seattle, X2 Biosystems.”

X2 Biosystems was founded in 2007, and is solely dedicated to developing products that are designed to solving the growing public concern for head injuries across all sports. This piece of white tape is their baby.

About the size of a silver dollar, the X2 Patch jams an assortment of bite-size technology such as a tiny gyroscope, accelerometers, and other miniaturized bits of equipment into a central hub, which stores or transmits the data to a nearby computer. The key component is a Microelectromechanical System, or a MEMS for short. They feature the same general parts that are essential to air bag deployment or car assembly line robots – the most important feature being the impact sensor.

This all began as sensors in football helmets and mouth guards. Anywhere someone could stick a sensor close to the skull, they did it. But while mouth guards were impossible to ensure constant, steady contact with the upper jaw and helmet sensors were placed in a unit meant to absorb impact, the readings were scattered and inaccurate. In came X2.

“Ideally, you’d peel back a piece of skin behind your ear and permanently mount our sensor on the bone and be done with it,” joked X2 CEO John Ralston. “But we’re kind of constrained to put it on the skin.”

Ralston also discussed challenges confronting a patch behind the ear, some of which is obvious. Skin movement can throw off readings. Sweat and high-speed movement can cause it to fall off. But according to Griffiths, that hasn’t been a significant problem. “Our players are very happy to wear the patches, and once they put them on they forget they’re there. We’ve already had players go straight into the showers with them still on because they forgot they were there.”

Taking it another step, what if a patch could give an instantaneous impact readout that could tell medical teams on the sidelines whether a player needed to come off? It would solve the problem of lengthy sideline diagnosis, and would relieve coaches faced with the dilemma of playing a man down or burning one of his substitutes

Unfortunately, it’s not that easy. Because of human variation, one player might be able to sustain a heavier blow without receiving a concussion, while another player might be more susceptible for a variety of reasons. Because of this, Ralston immediately shot down any possibility of the patch diagnosing a concussion, at least at this time.

“X2’s piece of the puzzle is simply providing tools to get more data about what happened,” Ralston said. “We still hand it over to the M.D.’s and the clinicians to make diagnosis, that’s not part of what we do today. It may be in the future, but [the patch] is still proving to be a phenomenally powerful tool for assessing head impact.”


The X2 Patch is visible behind the ears of Virginia Tech women’s soccer players in a game against Duke in September, 2014 (Photo Credit: Virginia Tech Athletics,

He’s not the only one that says instant diagnosis is either far away or impossible. “You’re never going to get to the point where it’s an absolute diagnosis,“ said Dr. Stefan Duma, department head of the Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences.

“I could measure 80 G’s [of impact force] on one player who could have a concussion, and I could measure 120 G’s on another player who’s fine.” Dr. Duma is known for purchasing every significant piece of technology developed in athletic head impact sensing and testing it on his own, as a third party. He has done extensive testing with the X2 patch.

“All [the X2 patch] does is give the physician a little more information. There’s so much variability, all it does is serve as an extra piece of information. Because we’re all different, it will never be an absolute diagnosis tool. It’s not like a biomarker.”

As part of his research Dr. Duma has applied the X2 Patch across every in the Virginia Tech athletic program, most extensively on the women’s soccer team this past fall season, alongside extensive video recordings to pair the digital readouts with what actually happened on the field. His findings for the current product are somewhat disappointing. While the complete conclusions on the X2 Patch won’t be published for a few more months, he was able to give a synopsis of what he found. As exciting as the prospect of the technology is, it’s clearly not yet suitable for full consumption just yet.

“I’m not discrediting it because they’re trying to solve a difficult problem, but it’s not ready,” said Dr. Cantu. “We were initially extremely excited about [the patch]. The problem here is there’s not a single peer review journal paper that shows the validation data. Our paper will be the first, and it will not be positive, so we will likely not be using the X2 Patch anymore.”

According to Dr. Cantu, the patch, in its current state, is wildly over-recording the number of impacts, almost to a 10-to-1 scale. “There’s two levels of accuracy. The first is does it accurately predict when a hit happened. These things are too light that their algorithm is not doing that correctly, it’s not telling you when the right hits happened, as much as one out of 10.”

“There’s not a solution for telling you how many hits actually happened that are real hits. So in a general sense, our girls when they practice or play a game, one practice or game will have about one head impact. But if you’re measuring 10 or 20 [in each] over the course of a season, it looks like the girls had a thousand head impacts.”

So obviously there’s much work to be done But according to Ralston, it’s not the obvious head impacts that are the only dangerous moments for athletes, it can be little motions that build up over time.

“One thing that four years of data has shown is it’s not just direct impacts to your head [that are dangerous],” says Ralston. “It’s any indirect impact that makes your head move suddenly. So heading a ball or simply taking a fall, or having someone bump into you shoulder-to-shoulder can set your head in motion, and at some point you stop moving but your brain continues to bounce around inside your skull.”

So while there seems to be some discrepancy on what should be measured and what shouldn’t, one thing is clear: with some refinement and upgrades, the X2 Patch could eventually be a revolutionary piece of technology that not only collects a heavy amount of data for further research into the dangers of head impacts in soccer, but also can potentially be a tool that aids on-field medical staffs to make quick diagnoses in a manner which impacts the sport itself less and therefore convinces managers and players to take the issue much more seriously than at the present time. And it’s just one part to the puzzle. Dr. Duma says he’s tested around 20 different products all designed to accomplish the same thing, and while none have stood out as quite ready, they all have positive outlooks.

X2 Biosystems has received plenty of play in American sports and around the world. Their logging software is being utilized by both the National Football League and Major League Soccer, with both leagues to provide every team with the software for next season. The software allows teams to make quicker on-field decisions as well as log problems for players for simple recall later, and allows medical staffs to create plans of recovery for anyone that has an issue.

X2 also had a mouth guard used in a wide-ranging study done by a New Zealand rugby league, and the findings were just published in the American Journal of Sports Medicine a few months ago.


X2 has begun testing on multiple products, including a headband and mouthguard in addition to the behind-the-ear patch, and they are using the technology to study the impact of heading a soccer ball on the brain (Photo credit: X2 Biosystems)

But the patch is only beginning to see use on the market, and Saracens were willing to take the first step. That step is a massive one. Saracens is undertaking a huge research project – with no guarantee of any significant results – simply for the betterment of its players who ply their trade in the inherently dangerous environment of professional rugby.

“This data is just one area we’re looking at,” said Griffiths. “We’re also shortly going to start taking blood tests and looking at biomarkers, so there are several areas of the research of which the X2 Biosystems product is just one.”

“We hope to have some answers - or some preliminary answers - later in the summer, but we don’t know. There’s no guarantee, we’re setting off to find some answers, whether those be sooner or later, we simply don’t know.”

What exactly are the questions to which Saracens is searching so vehemently for the answers? That would require another full writeup altogether. But Griffiths was adamant that the end result is the important part, not the question itself.

“We don’t want to be visiting our players in 20- to 25-years’ time and find them suffering from some kind of neurological disease or from dementia and think back and say ‘well, back in 2015 we sort of thought something was going on, but we didn’t really know.’”

It’s time soccer teams began to care about the well-being of players as much as this rugby club. And while it’s not perfect, the X2 Patch isn’t just a cool gadget you look at, think “wow that’s cool” and move on with your life. It’s a potentially game-changing piece of technology that hopefully, with more time, effort, and development can provide players and coaches with a never-before-seen avenue to channel their in-game thought processes not just on winning a match, but staying safe in the process. That’s the real challenge.

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