Everything we know about concussions is wrong

The risks are clearer, the causes are still murky.
The risks are clearer, the causes are still murky.
Image: Unsplash/Ben Hershey
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I’ve never had a concussion, at least not that I know of. There was this one time, when I was about seven, when my sister threw a rock at me and nailed me above my right eye, but I didn’t lose consciousness or forget who I was. My father, a doctor, responded to my screams by asking me to follow his finger and tell him what day it was. When I answered correctly, he handed me a bag of frozen peas to put on my eye and told me to let him know if I started to feel “weirdly tired.”

That was three decades ago, when concussions weren’t a big deal. As far as head injuries went, they were often seen as a blessing, a narrow escape from more serious trauma. At least you didn’t get your head split open. Shake it off, rub some dirt on it, and get back in there.

Then we discovered that football players, men who knock heads for a living, are riddled with CTE (chronic traumatic encephalopathy). We also learned that one concussion can in some cases be one too many, and that an accumulation of concussive episodes early in life is almost certain to cause long-term mental and/or physical problems.

It’s no longer acceptable to tell an athlete, of any age, to “walk it off.” But what do we tell them instead?

Daniel Torres is a neurologist at the four-year-old Concussion Center at New York University’s Langone Health Center. His doctor’s wall—where all the certifications and degrees hang so patients know they’ve come to the right place—has more framed bona fides than plaster. In a no-nonsense voice perfect for soothingly informing worried patients of their options, he tells me the first step in treating a concussion is figuring out what particular variety of concussion it is.

“Wait,” I say, “there’s more than one kind?”

The pornography of head injuries

Most people know what a concussion is, just don’t ask them to define it. This is true even for those who make concussions their business. Robert Cantu, clinical professor of neurology and neurosurgery and co-founder of the CTE Center at the Boston University School of Medicine told me it’s “traumatically induced strain to the brain.” But he couldn’t tell me definitively what kind of strain, or what the strain does to the brain. There are theories, but nothing confirmed.

“As of today we don’t have a biomarker, an image study, or a blood test that reliably tells when a concussion happened and when a concussion is cleared,” says Cantu. The state of the art is: you’ll know it when you see it.

Steve Broglio, an associate professor of athletic training at the University of Michigan, has spent a fair amount of time on the sidelines over the course of his career. After any bone-jarring play, he says, you get to look at the athlete and then it’s more or less a judgement call. “It is my opinion of the athlete when he or she presents to me,” says Broglio. “That’s a massive problem we face as a field.”

It’s impossible to help people you don’t know are suffering. And many athletes, afraid of losing playing time or being benched, actively try to cheat diagnosis. The lack of an objective diagnostic tool means many concussions can go undetected.  It also means we have no way of knowing for sure when someone has fully recovered, so we could be sending people back into work or into a game before they’re physically ready. At best that can prolong healing times, at worst, another concussive event could lead to second-impact syndrome, a swelling of the brain that can cause permanent damage, or sometimes death.

Going into the 2009 NFL season, the league began to accept that it had a concussion problem, it banned the wedge and bunch formations, formations where players group together and run full-speed at the opposing team during kickoffs. Since then the NFL has also set limits on how and when players can unload on each other, adding more circumstances and positions to what they call “defenseless players,” and limited the number of full-contact sessions teams could have during training camp prior to, and practices during, the season. In 2013, the NFL enacted concussion protocols to identify and treat the injury going forward, with hefty fines for teams failing to implement them.

Image: giphy /

Since the NFL only started keeping records in 2012, there aren’t a lot of official data, but the little we have are not that encouraging: there’s been no significant dip in the incidence of concussions among NFL players over the past five years.

One problem is that we may be looking at the physics all wrong, says Jamshid Ghajar, director of the Stanford Concussion and Brain Performance Center.

In our sea of ignorance, we thought if we knew anything, we knew helmets would help. Encasing a head in a hard, plastic sheath prevents injury; make that sheath better, prevent more injury.

The NFL ended their exclusive licensing deal with helmet-maker Riddell after the 2013-2014 season. Though players could always wear any headgear they wanted, it had to have a Riddell logo, and thinking a helmet is a helmet, most chose to go with the Riddell VSR4, a model essentially unchanged from helmets designed in the 1960s. Back then, a helmet was tested and considered effective if it prevented corpses from getting skull fractures when researchers hit it with hard objects. The closest there is to a federal regulatory authority on helmets, the non-profit National Operating Committee on Standards for Athletic Equipment (NOCSAE), research and sets minimum standards for safety, but their standards are more about impact, are pass/fail, and there are no national requirements to use certified models.

In 2011, following up on research started in 2003 attempting to measure the impact forces their football players were exposed to, researchers at Virginia Tech developed a 5-STAR rating system for helmets. “The “S” in STAR is summation,” says Stefan Duma, professor of biomedical engineering at VT. “Every helmet is tested 120 different times, different energies, different directions, and then we aggregate all those tests to one star value.” The higher the STAR rating, the lower the force experienced by a player wearing the helmet. On the one to five scale, the VSR-4 scored a one.

Duma says his research indicates helmets can help, “We followed eight football teams for a year, and we proved that switching from a one-star to a five-star helmet can reduce concussions by half.” The NFL is banking on that. In 2016 the league invested $60 million towards a project called the “Engineering Roadmap,” to research, design, and test equipment innovations. And new helmets like Riddell’s Speedflex, and the highly-touted VICIS Zero 1, were designed specifically with concussions in mind.

Newer research that aggregates readings from helmet sensors to measure the impact exposure of different positions found (predictably) that linemen knock heads much more than kickers. This has led to some calls for position-specific helmets designed to protect against the unique kinds of impact each position experiences.

Ghajar argues that none of that will matter. “Until the game is about people running around trying to hit each other in the head with hammers, helmets aren’t going to do much,” he says.  He’s one of a growing number of experts making the case that preventing concussions is less about protecting the head from the force of the impact and more about stopping the head from moving around when it’s hit (or even when it’s not).

It’s not the size of the hit, it’s the motion in the ocean

Stephen Olvey, an associate professor of clinical neurosurgery/neurology at the University of Miami-Miller School of Medicine, is another. Olvey started his career in auto-racing back in the 1960s while he was still in medical school. He started out in the first aid tent, then eventually worked his way up to medical director of all Championship Auto-Racing Teams (CART), a now defunct open-wheel racing league (like IndyCar and Formula 1). Olvey served in that capacity from 1978 to 2003. He’s got an easy way of talking that makes it hard not to picture him working in the pits, topped with cowboy hat, complete with a cigarette hanging from his lips.

I asked him how a sport where everyone’s inside a car, essentially a protective metal frame, could have a concussion problem. “Imagine if one out of every seven NFL players was killed every year with a bad head injury,” he answered. That’s how it was for high-level professional racecar drivers in the 1970s, when racing was forced to carefully look at head injuries and helmets.

They quickly identified the problem, for this kind of racing at least, “Impact was not the most important thing,” Olvey said, “it was how much the skull is put in motion as a result of forces that affect the head.”

Most of the experts Quartz spoke with agree: you don’t even need to get hit directly in the head to sustain a concussion. A sudden and drastic change in acceleration is all that’s required to deform the brain inside the skull, and if the rate of change is sufficient, to induce traumatic brain strain.

If you’re in motion, then forcibly and suddenly stopped from being in motion by, let’s say, a giant, 350-lb-mountain-of-muscle who can deadlift a Volkswagen and run like a gazelle, a helmet may stop your head from splitting open. But the helmet won’t stop your brain from bouncing around the inside of your skull like a rubber ball thrown hard into a cardboard box. Shake an egg hard enough and the yolk will scramble despite the shell remaining intact.

The same holds true when a still brain is suddenly thrown into motion, like when a boxer gets hit with a right cross to the jaw.

In either case—boxing haymaker or football tackle—the head moves, or stops moving, immediately. The jello-like brain that’s floating in the skull, surrounded by shock-absorbing membranes called meninges, is always late to catch up. The brain distorts, sheers, bounces, and can even come loose from its moorings.

Image: giphy /

This is why helmets can’t do all that much to help with concussions. “The momentum and energy that’s transferred to the head [at impact] is not prevented by slowing things down within the range that a practical football helmet could do,” says Phil Bayly, a professor of mechanical engineering at the Washington University in St. Louis, who studies how the physical material of our brains react to motion. “The skull stops, the brain wants to keep on moving.”

Bayly and his team use MRIs and strobe-lights to take pictures of a cadaver’s brain case while the body was moved to simulate motion. Even when moving at a fraction of the speeds reached by athletes in game time situations, or a car crash on a racetrack, or even a soccer ball bouncing off the back of a person’s head, the brain still shows visible distortion, says Bayly.

Tagged MRI of the brain during mild angular acceleration of the skull.

It’s widely believed that rotational acceleration, where the head turns instead of moving front to back, is particularly dangerous. Going back to the jello comparison, Bayly says if you slap the mold on the top, the shock will ripple to the bottom, and bounce back, the jello no worse for wear. But consider what would happen if you were to pick up the plate the mold was on, and twist it like it’s a steering wheel and you’re about to miss your right turn. You’d have quite a mess on your hands. If engineers could figure out a way to stabilize the neck to prevent the violent swings of the head that scramble brains within the skull, says Ghajar, maybe we could prevent concussions.

Olvey says open-wheeled auto-racing’s success in solving its head-trauma problem adds evidence to the theory. Inside the cockpit of all open-wheeled race cars, there’s a restraint device called a head surround, that literally surrounds the driver’s head, keeping it motionless and looking forward. Coupled with the HANS (head and neck support) device, the head surround ensures that inside a race-car, a driver’s head, neck, and thorax become a single, rigid unit, always moving in the same direction, front to back, never turning. There’s been some form of this restraint in every open-wheeled racing car for several years, but prior to 2014 drivers could turn their helmeted heads a few degrees left or right. Now they can’t turn in any direction whatsoever for the entire race.

Image: giphy /

Since deploying that new, more rigid, system, says Olvey, “there has been only one suspected concussion in IndyCar racing,” which turned out to be a misdiagnosis. From 2012 to 2014, says Olvey, there were five documented concussions in IndyCar. While that’s nothing compared to the number of concussions in the NFL, it is the type of progress that can help teach us what types of solutions actually work.

Obviously there’s no head surround for football. Athletes need to be able to move their heads on a swivel (as they tend to say), and the neck just isn’t strong enough, even on the beefiest competitors, to handle the kind of forces generated during most impacts. Also, for the neck to be of any help at all, the player has to see the hit coming. And sometimes everything simply happens too fast. The impact is over before the body has time to respond.

An army of treatment

Most concussions resolve within days, but in up to 20% of cases, symptoms can linger for weeks, even months. Rarer, but not unheard of, are cases that never resolve. Torres, of NYU,  says most of his patients are among the long-term sufferers, the 20-percenters. They come to him with persistent difficulty falling or staying asleep, dizziness, headaches, tinnitus, a hard time accessing memories, and/or an overall fuzziness of thought. Sometimes they complain of depression or a sudden propensity to anger.

The issue is that all of these could indicate of any number of other conditions. And the more time that passes between injury and diagnosis, the harder it becomes to link present symptoms with previous head trauma. By the time a patient gets to him, says Torres, he’s not so much trying to determine whether or not the patient is suffering from a concussion as he is trying to to diagnose the dizzying array of symptoms that a patient’s concussion could present itself.

Torres begins his assessment by asking questions—“Where are we at today?”, “Did your team win the last game?”—from the SCAT5, the fifth iteration of the Sport Concussion Assessment Tool.

The test is designed for assessment during an in-game experience and, Torres admits, a little silly in a clinical setting. But he adapts the questions to a non-game setting to assess a cognitive baseline; rather than ask what the score of the game is, he’ll ask if what the weather is like, or what a person had for breakfast. He uses the SCAT5 framework to measure the value of a person’s cognitive function when he first sees them, to establish a baseline against which future progress can be measured.

After the SCAT5, he runs more cognitive tests, tests to measure balance, and asks questions to assess the patient’s quality and quantity of sleep. He’ll have the patient follow the point of a pen with their eyes to evaluate how well they’re seeing and orienting to the space and environment. Lastly, he orders imaging tests of the brain and nervous system, and physical exams to rule out any structural damage.

Torres then evaluates the results from the tests and the questionnaires and assigns the patient to a treatment schedule. It could include working with any combination of the dozens of different specialists available to the concussion center, including neurologists, neuro-ophthalmologists, physical and occupational therapists, and audiologists. Since concussion symptoms can change over time, and there’s no telltale marker to indicate the extent of recovery, treatment will continue to be a conversation more than anything else.

“There’s just not amazing science in the field in general,” says Torres. “So you have to decide which not-so-great science are you going to follow.” Those are not exactly the sorts of words you want to hear at a doctor’s office.

Getting our legs under us

Ghajar, at Stanford, thinks he’s developed a device that can both better diagnose, more effectively monitor, and could possibly help prevent, concussions. His device is based on the idea that our eyes provide insight into how our brains orient and coordinate our bodies in time.

“Our brains are actually two and a half seconds in the future,” says Ghajar. “By the time you sense something, it’s already happened. We anticipate the future, interact in the present, and are aware of the past.” To hit a tennis ball screaming down the line, a person’s brain has to anticipate where that ball will be, and react before it gets there.

Everyone’s life is lived on a slight time delay. But when someone has a concussion, that whole system gets out of whack. It makes people feel literally “out-of-sync”—symptoms sometimes described as “brain fog” or being “dazed,” says Ghajar. He built a system to measure that disconnect with eye-trackers and a Samsung Gear VR headset.

“EYE-SYNC Technology,” as he calls it, measures a person’s ability to maintain what’s called smooth pursuit with their eyes. Basically, it analyzes how the eyes perform when tracking words across a page or an object in motion. There’s a diagnostic standard called the King-Devick test that measures this ability, but it requires that someone observe and interpret eye movements as the patient reads numbers off a card. Ghajar’s EYE-SYNC can do the same, but in much less time, and without all that pesky human error.

The subject is fitted with a modified Samsung VR headset equipped with the latest eye-tracking technology, and told to follow a virtual dot as it traces a circle across the screen.

At a recent conference, Ghajar showed two videos demonstrating the technology in action. The first showed a normal, predictive brain state: the subjects’ eyes always tracked slightly ahead of the dot they were told to follow, leading smoothly and anticipating the predictable pattern of the circle. The second was of a concussed brain. Here, the eye-dot was shockingly sporadic, jumping in front of and falling behind its intended target, with no clear system or pattern. It was pretty clear all systems were not go.

Ghajar says the technology can also also pinpoint attention deficiencies in a person’s visual field, and improve them. He has been working closely with Stanford athletes, all of whom are required to undergo baseline tests with the EYE-SYNC device. Results from some athletes’ tests suggested they might not notice things coming from the lower left as well as from other angles. When the trainers found this out, they worked with the athletes to train away those weaknesses.

This sort of approach could prevent concussions, Ghajar says because more often than not, it’s the hit you don’t see coming that knocks you out.

The road to recovery

W.H. Earles, writing in the Journal of the American Medical Association, said that, “Every case of recent head injury, however trivial it may appear, should, we believe, be treated with the greatest consideration, lest damage to hidden and important structures escape our attention, thus leaving a foundation for future trouble which too often is irreparable.”

Earles wrote that in 1903. Football has always had a problem with concussions, but without visible damage to assess and the fact people walked away soon after the injury, it was hard to make the case that it was a big deal. And that attitude stuck around for almost a century.

In speaking with Mara Sproul, a program manager at the Concussion Center, I recalled watching NFL games in the 1990s, and seeing players get the sense knocked out of them on first down, and go back in for third. She told me she remembered when people thought it wasn’t a concussion unless someone lost consciousness.

“People laughed at [concussions] 20 years ago,” says Broglio, “it’s only been in the last 10 years that the money, resources, and attention have been there to push the field forward.”

According to the US Centers for Disease Control, from 2001 to 2010, the rate of American emergency room visits for traumatic brain injury nearly doubled (from just over 400 to more than 700 per 100,000). Though this sounds like grim news, it actually may represent a sobering sign of progress.

The increase in concussion cases doesn’t mean people hit harder now, or that there are more horses to fall off of—one study found that horse accidents accounted for 42.5% of all adult TBI events between 2001 and 2012—or even that we now are more diligent in spotting them. What the numbers are most likely showing is that more and more people are becoming aware of the dangers and are motivated to seek help. As a result, during that same decade-long period that saw US emergency room visits double, the number of deaths due to TBI saw a steady decline.

Hopefully these positive trends are a direct result of the public coming to grips with the true nature of these injuries. Even if a person is able to walk away from an accident, a pile-on, or a vicious hit that makes a stadium wince in unison, that does not mean they escaped unharmed. Though we are only starting to learn what’s going on behind a sufferer’s eyes, what we now know for sure is that telling anyone to walk it off, to get back in there, is not, and has never been, enough.

Correction: This article has been updated to more accurately describe the role of the NOCSAE.