Neurologists describe a concussion as a neurometabolic cascade. I hear that term and I fall into a dream of psychedelic waterfalls, of fireflies twinkling at twilight, of a seascape speckled by the starry-eyed blinking of the moonlight.
All that could not be further from reality. Sure, sometimes people ‘see stars’ when concussed. Other times they black out. And at other times, they see nothing at all. They may not even know they’ve been concussed. A concussion doesn’t even require head contact. It’s ridiculous that so many of us can earn the same injury but in such vastly different ways, and with different outcomes.
Not long ago, few in the sports world or even the medical community took concussions very seriously. You got your bell rung, big deal. You only had a concussion if it knocked you out or you weren’t sure what day it was.
Now, concussions are one of the hottest topics in sports medicine. In hockey we learn about another concussed player every other day– news brought to us with plenty of doom and gloom:
“The names pile on top of one another like a giant mound of hockey sticks in the world’s biggest pickup game. Evgeni Malkin. Rick Nash. Jeff Skinner. Ryan McDonagh. Vladimir Tarasenko. Only this is a contest you don’t want to play in or watch. This is the concussion game.” Adam Proteau, The Hockey News.
Proteau is a pro hockey insider who has more admirably written on the subject before, but other, more reactionary responses have been coming from a variety of other angles, including:
- Parents: One Canadian parent, seemingly caught up in the frenzy, suggested that anyone who permits their child to play contact ice hockey should be charged with child abuse.
- Non-hockey experts: The obligatory statement by the distinguished hockey outsider, in which the initial admiration for the beauty and skill of the sport is violated by the abject horror of fighting and other violent plays.
- Mainstream media: “Inside the Brain Lab” was a pumped up CBC special report from 2011 that so badly milks the issue for urgency that it is at times embarrassing to watch. Referring to one infamous head injury suffered by Sabres legend Rick Martin, correspondent Peter Mansbridge tries to lead Dr. Ann McKee by asking, “Would it surprise you to learn that [disease in Martin's brain] could happen from one concussion?” Yes, she says after a long and uncomfortable pause, that would surprise me, because it is extremely unlikely and there’s no evidence to support it.)
It’s concussion madness! Concussion mania! and it too shall, not pass, but eventually subside and we will settle into a more comfortable relationship with the mild traumatic brain injury called concussion. It will be an inevitable aspect of sport and of life; we will not fly into a panic each time another player is concussed or use the occasion as a springboard to further points of view. Instead, the concussed player at all levels of hockey will have his or her injury managed and treated appropriately like any other injury, so that they may get back to where they want to be: on the ice.
After all, the only way to end concussions in the sport of hockey is to shut down the sport of hockey. Good luck with that.
With that in mind, let’s meander through the minefield of the concussion.
CONCUSSION NUTS AND BOLTS
A concussion is defined as “a clinical syndrome characterized by immediate and transient alteration in brain function, including alteration of mental status and level of consciousness, resulting from mechanical force or trauma.” How do you diagnose that– Blood test? X-ray? MRI? No.
A concussion is a fully clinical diagnosis, meaning it’s an evidence-based ‘best guess’ that leans on symptoms, history, and any other data you can collect. No broken brain bones to image or concussed neurons to biopsy. A person may wrongly think they’ve never been concussed or wrongly think they have.
Here’s a concussion, one of the many concussions Devils defenseman Scott Stevens handed out during his career. Eric Lindros is moving across the Devils line with the puck when Stevens catches him in the jaw. Eric’s head snaps back. What you can’t see is the actual concussion: the action of the big man’s brain. Unlike the rest of his body, which has largely come to a stop, his brain is still cutting over the line, headed for the slot. It isn’t injured when Stevens delivers the shoulder; it’s injured when it collides with the inside of Lindros’ skull. The same is true for when Eric hits the ice. His head travels down, in the direction of the ice. It meets the ice, an immovable object. It bounces back up, while his brain continues downward and slams into the back of his skull.
What is believed to be occurring inside Eric’s head is that the force of his momentum causes the neurons in his brain to stretch or elongate. (I can’t help but see the iPad’s “pull-to-refresh” feature here). In that state, chemicals flow into the neuron and others flow out, creating an imbalance.
“Ten to twelve years ago it was smelling salts and ‘how many fingers am I holding up?’ and now the pendulum has swung entirely in the opposite direction,” says neuropsychologist Dr. Michael Collins, the Executive Director of the Sports Medicine Concussion Program at the University of Pittsburgh Medical Center (UPMC) and a familiar name in hockey circles, especially in the northeast. “But we’ve still got a lot to learn with this injury.”
Every complex scientific subject requires an eloquent insider to deliver the concept to the public in digestible form. Relativity and the mass-energy equation had Einstein; the cosmos, Carl Sagan; black holes, Stephen Hawking. Concussions just might have Michael Collins.
“Concussion is not the bogeyman,” Collins tells me. I’ve read that statement from him before and I wonder why it hasn’t sunk in with he public yet. “Rather, it’s a metabolic crisis. Chemicals leak out of neurons and others leak in. There is an energy demand that’s not being met through bloodflow and we know that can affect specific systems in the brain. A lot of research has been carried out demonstrating which systems are vulnerable and how to measure them, and we’re getting better at learning how to rehab those systems.”
This approach–of determining what areas of the brain have been disrupted and designing a treatment protocol accordingly–is the evidence-based foundation of how concussions are managed at UPMC, and progressively, all over North America.
“This field has moved forward so rapidly because we finally found a way to measure [concussions].” Collins is referring chiefly to ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing), an increasingly utilized neurocognitive testing tool that provides coaches, team trainers, and players with baselines that can then be used in various ways to put numbers to a person’s mental performance before and after a potential injury. ImPACT’s validity is supported by over 150 peer-reviewed papers and untold hours in the clinical trenches, and decision makers such as high school coaches like it because it takes the decision of whether a player is ready or not out of their hands. “It’s not perfect. But it works when coupled with a good clinical interview, a good examination, and a good understanding of how the injury breaks down. ImPACT is an objective piece of information in an otherwise largely subjective protocol.”
The program has now broadened to become an aspect of youth sports communities throughout the United States. However, ImPACT does more than just establish a neurocognitive baseline, according to Anne Mucha, DPT, a board certified neurologic physical therapist at UPMC and widely regarded as one of the foremost experts on vestibular rehabilitation therapy following concussions.
“ImPACT makes everyone involved in youth sports–parents, kids, coaches– more aware of the dangers of a concussion,” she says. “Whether or not the baselines prove to be one hundred percent valid or not, people are more mindful now. More hesitant. Instead of saying ‘Oh Johnny’s fine, send him back out’ the mentality is changing and now it’s more ‘Well, let’s sit him out and see what’s going on first.”
As a vestibular [i.e. inner ear, systems of balance and vision] rehabilitation therapist, Mucha is on the very front lines of concussion management, working directly with patients in creating treatment protocols unique to the individual.
“Vestibular therapy has been around a long time. It can treat problems arising in the inner ear, problems from migraines, and problems arising from similar brain conditions. So we extrapolate from that body of work the idea that it can enhance recovery from concussion, and it works. The brain is a plastic system. It’s modifiable through sensory adaptation and exposure.”
I tell Mucha that I can ruin my entire day by trying to read in the car. “That’s actually something we ask patients when they come in. We want to know about any sensitivity to motion before the concussion happened. Could you read or send a text in a moving car, things like that. And if you have those issues you’re probably pre-disposed to having vestibular issues from a concussion.”
“Concussions play dirty,” says Collins. “They hit you where it hurts. Every patient has constitutional factors that make them more susceptible to concussions–what you bring to the table from a central nervous system standpoint, that’s where we’re going to look first.”
The unofficial doctrine of the current concussion mania includes the idea that one concussion is all anyone needs to be on the train to progressive brain disease, a notion Collins refutes with one of his best-known statements. “Concussions are like snowflakes- no two are alike. This neuro-mythology in circulation suggests that one concussion creates permanent damage. I strongly believe that if we treat and manage the original concussion properly, we can hit the reset button on the brain.”
CONCUSSION FAST FACTS
- Incidence of sports-related concussions in the US annually: 300,000
- Likelihood that an athlete in a contact sport will sustain a concussion in a given year: 10-19%
- Period in which the majority of hockey concussions occur: 2nd*
- Position most associated with concussion: None- distributed equally among goalies, defense and forwards*
- Percentage of concussions that feature a loss of consciousness: 10%
- Number of deaths believed to be a result of so-called second impact syndrome in the last ten years: 30-40
- Estimated percentage of concussions not reported by athletes: 49%
*From a prospective 1996 study of the Swedish Elite League.
Chronic traumatic encephalopathy is a tauopathy: a neurodegenerative disease defined microscopically by the progressive collection in the brain of an abnormal protein called tau.
The evidence suggests that a person can develop this disease following repetitive, mild traumatic brain injury. The precise cause-and-effect relationship between the two is not understood.
This is the brain disease we’ve heard so much about in recent years that is being diagnosed post-mortem in professional athletes.
Progressive cognitive impairment, progressively dramatic changes to behavior and personality, so-called Parkinsonionism (not Parkinson’s Disease, but symptoms similar to it), as well as abnormal speech and gait are all associated with CTE. It is an unquestionably insidious disease that currently has neither cure nor mitigating treatment.
CTE shares characteristics with other neurodegenerative disorders, such as Alzheimer Disease (AD), progressive supranuclear palsy, and post-encephalitic Parkinsonism. However, it is regarded as being neuropathologically distinct with “a clear environmental etiology.” That ‘clear environmental etiology’ refers to the belief that the origins of CTE are in repeated blows to the head.
“The best way to understand CTE is to look at boxing,” says renowned neurologist Dr. Barry Jordan, and in fact, CTE first appeared in the medical literature in 1928 when Harrison Martland, a New Jersey pathologist, published a paper in the Journal of the American Medical Association under the no-nonsense title, “Punch Drunk”. He describes this term as ring parlance for a boxer who has endured so many blows to the head or jaw that he’s clearly and permanently neurologically impaired.
When Boston University researchers reviewed the four dozen or so cases of neuropathologically verified CTE in the medical literature in 2009, the overwhelming majority were boxers. ”The New York State Athletic Association, by way of boxing, has pioneered our understanding of the disease.”
A widely respected sports neurologist, Dr. Barry Jordan is the Chief Medical Officer of the New York State Athletic Commission, a team physician for USA Boxing, the assistant medical director of Burke Rehabilitation Hospital, and he serves on the National Football League Players Association (NFLPA) Mackey-White Traumatic Brain Injury Committee and the National Football League (NFL) Neuro-Cognitive Disability Committee.
“Studies of boxers and brain trauma go back decades. And today, if you want a license to box in New York State you need to have an MRI of your brain. That’s unprecedented.” Dr. Jordan concedes that the imaging technique doesn’t help with concussions but it does expose lesions that can predispose a boxer to brain injury. “We require that they be scanned every three years, so you can actually identify in some boxers progressive changes over time.”
If there is a genetic component to concussion vulnerability, perhaps there is one to CTE as well since it’s not in the brain of every autopsied athlete. “A few studies have suggested a genetic predisposition,” he says, neglecting to mention that he is the lead author on a couple of them, “although it hasn’t been fully demonstrated yet.”
If boxing has pioneered the scientific understanding of CTE, then football has delivered it to the public. High profile suicides by former NFLers such as Ray Easterling, Dave Duerson and Junior Seau, followed by the post-mortem diagnosis of CTE, will do that for you.
Some four thousand retired football players have filed lawsuits against the NFL arguing that the league failed to properly address concussions and traumatic brain injury, and that it knew enough about the issue to do something about it. The immediate problem with such a lawsuit is obvious: the NFL is not a medical entity. It gets its medical direction from doctors. As health care and law expert David Orentlicher wrote,
“One can easily think that the [NFL] was too slow to worry about the medical consequences of head trauma. But the extent to which its response was unreasonable is unclear. If many medical experts did not worry about concussions, it is difficult to fault the NFL for not worrying either.”
Of course, the sport of football has always been plagued with injuries, especially head trauma.
Back in 1931, the American Football Coaches Association conducted the first survey of football fatalities resulting from head trauma. After 35 years the torch was passed to the University of North Carolina at Chapel Hill, where the annual survey continues to this day, and considers all major levels of football. Now in its ninth decade, the year 1990 stands out as being the only year in which a football fatality was not recorded. This contrasts sharply with the 36 direct football fatalities in 1968.
In the wake of that tragic year, the National Operating Committee on Standards for Athletic Equipment (NOCSAE) was formed, which overhauled football helmets and in 1973 established standards that form the foundation of the standards active in the NFL today.
Granted, the manner in which the NFL responded to the Mike Webster lawsuit– in which it repeatedly tried to discredit any notion of a link between head trauma and mental illness– is something of a black eye, but the NFL is emerging as the leader among pro sports in confronting the issue.
As recently as Super Bowl XLVII in 2013, the league announced it would have independent neurologists on the sidelines next season to evaluate players who may have experienced a concussion. According to Dr. Jordan, the NFL will also feature trainers in the upstairs booth to monitor players on the field in the event trainers on the ground are otherwise preoccupied.
The idea that doctors should be independent is not entirely new, of course. One of Adam Proteau’s recommendations to the NHL is to free up the physicians who make these diagnoses from having any team affiliations, since there seems to be a conflict of interest.
Like NFL fans, hockey fans need to get used to reading about the dissected brains of their aging heroes. What began with Bob Probert and Reggie Fleming has continued through Rick Martin: the post-mortem diagnosis of CTE. It has continued even with the 28 year old enforcer Derek Boogaard. Meanwhile, several retired NHL players including the likes of Keith Primeau have already signed off to donate their brains to science, joining some 500 other athletes.
The NHL’s stated policy is not to release hard numbers regarding head injuries and concussions. You don’t have to believe in the grassy knoll to think that they’re concealing this information for very good– and not terribly flattering– reasons. Regardless, in 2011 Kris King, the NHL’s Vice President of Hockey Operations, released some concussion statistics for that season through 1 March, as he explains in the video above:
- 44% from legal hits
- 26% from accidents
- 17% from illegal hits
- 8% from fighting
As Gary Bettman is fond of saying, hockey is a fast game played in a closed environment. To that end, some concussions are unavoidable. Few would disagree. What many take exception to is the league’s actual dedication to reducing concussions and other forms of TBI. Opposing fans want stiff, message-sending penalties to players who are still taking head shots or sending guys head first into the boards.
President Barack Obama recently told the New Republic that:
“[I]f I had a son, I’d have to think long and hard before I let him play football. And I think that those of us who love the sport are going to have to wrestle with the fact that it will probably change gradually to try to reduce some of the violence … I tend to be more worried about college players than NFL players in the sense that the NFL players have a union, they’re grown men, they can make some of these decisions on their own, and most of them are well-compensated for the violence they do to their bodies.”
This is an important point. Back in July I wrote about how Gary Bettman’s approach to concussions resembled the manner in which Big Tobacco publicly fought damaging claims about its product for so many decades. The theme was that this was Bettman’s problem and something he needed to do more about.
The analogy with Big Tobacco remains entirely valid. But the notion that this is his problem does not. This is why the players pay Union fees. It is the responsibility of the PA to worry about the players– today, in five years, and in fifty years. The NHL’s primary responsibility, as we saw in the lockout, is to its bottom line. Since fights and big hits are good for business but losing players to concussions is not, it seems reasonable for the league to act according to those interests. Otherwise, the only obligation it has to the issue is a moral one.
BEYOND FOOTBALL AND HOCKEY
The growing impression is that this degenerative disease is endemic in athletes who play high-contact sports. But is it really so limited?
Verified mild cases of CTE have indeed been found in former football players, boxers, and former hockey players. But it has also been found in professional wrestlers who used steroids, soccer players who ‘regularly headed the ball’, domestic abuse victims, circus dwarfs who took part in dwarf-throwing events, and even concert-going “head bangers.”
In fact, emerging evidence shows CTE can also develop in soldiers who have been exposed to blast waves.
If concussions are now seen as endemic, they are endemic not because hockey, or any other sport, is played the wrong way, but because the human body is not designed to safely prevent the soupy brain from maintaining momentum in any direction and slamming into the skull when the rest of the body has stopped.
“The brain,” says Collins, in what amounts to his most troubling soundbite, “is an egg yoke inside an egg shell.”
For one minute, watching Jeremy Roenick make a case for shrinking player pads during a recent NHL broadcast, it looked like we might have a meaningful dialogue in hockey about reducing equipment size and strength across the board, making players feel less like linebackers in full body armor and more attuned to the pain involved in throwing a hit as well as taking one. Then, along came hockey’s idea of a buzzkill, Matt Cooke. His skate stomped down on the heel of reigning Norris Trophy winner Erik Karlsson, slicing it open. All of the sudden, the conversation shifted to making hockey socks from kevlar. Kevlar!
This field is an arms race, with each new innovation spurning on the next. How long before all the equipment is made of kevlar?
The number of lives saved by the helmet in the NHL can only be measured by how many lives were lost before and after the helmet became mandatory in 1979-80 for all players new to the league. In 1968, 51 years into the history of the National Hockey League, Minnesota North Stars forward Bill Masterton became the only player in that history to have died as a direct result of hitting his head on the ice. He was not wearing a helmet. Would it have mattered if he was? Well, it would not have made things worse. But one death in 51 years, and none in the 45 since, means that statistically the number of lives saved by the helmet is somewhere between zero and one.
In fact, the NHL’s safety record as regards head injury and death is sparkling compared to Sweden. The helmet has been mandatory in Sweden since 1963, and no deaths have occurred since then. But in the decade leading up to 1963, 16 players died due to head injuries.
Nonetheless, helmet standards and better helmet design are closely associated with a reduction in fatal or catastrophic head injuries in hockey at all levels. Had Lindros not been wearing a helmet when Stevens flattened him, who knows whether he would have survived that hit. There’s no denying the incredible contribution helmets have made towards player safety, but they are also associated with a bump in the rate of concussions, although this could be a consequence of detection bias—greater awareness of the problem, in other words.
Lately there have been a handful of initiatives to create a safer helmet. Dr. Collins, Dr. Jordan, and Dr. Michael Stuart, the Medical Director for USA Hockey and a consultant to the NHL Player’s Association, told me they’re all for the effort and the work put towards developing better, safer equipment, but that a safer helmet would contribute nothing to concussion prevention. “No helmet can mitigate this injury completely,” added Collins. “They’re going to happen. The bigger issues are, how do we properly manage them; help them heal; and get them back into play.”
As far as the potential for a safer helmet to mitigate the appearance or severity of CTE, Dr. Jordan says it’s anyone’s guess. “No one knows whether a better helmet can protect athletes against any long-term consequences.”
According to Dr. Jordan and others, and contrary to some public perception, mouth guards do not prevent concussions. Instead, mouth guards provide some protection against oral and dental injury. The debate is over whether mouth guards contribute anything towards the protection of a hockey player in any manner against concussion or TBI. Some emerging evidence suggests that while they do not prevent concussion, mouth guards might have an impact on concussion symptom severity–notably, mouth guards appear to have demonstrated an ability to decrease the severity of symptoms in concussed players who use them compared to those who do not.
… But stop and think about that: how would you really know whether concussion symptom severity is decreased in players with mouth guards? Ethically you can’t explore it using the gold standard of clinical trial design, a randomized, double-blind prospective trial. You can’t carry out a study in which you take a bunch of hockey players, give only half of them mouth guards, subject them all to concussions, and measure severity. The best you can do is to take a retrospective look at a set of past concussion events, determine severity according to an acceptable scale if you’re fortunate to find some reasonably consistent documentation of it, then determine whether the player wore a mouth guard.
Unfortunately, this approach runs counter to so many of the things we’ve learned about concussions. It says nothing about the kind of hit that caused the concussion. It fails to reflect the belief that every concussion is different. It says nothing about whether the players had a history of concussions, or a history of migraines, or any other genetic or physiological susceptibility.
There are enough confounding variables to reduce whatever information you can collect to being no better than a stack of anecdotes.
Gary Schwitzer, a leading voice in ethical health journalism and publisher of HealthNewsReview.org, has a saying:
The plural of ‘anecdote’ is not ‘data’.
Put another way, you can have a hundred anecdotal stories that testify to an idea, but together they don’t amount to anything that bears any resemblance to scientific evidence supporting that idea. The most important thing about the scientific method is that it demands an environment that can be reproduced so that others can test it too. There’s no point in reproducing an anecdote. And you certainly don’t want to reproduce a concussion.
So, what’s in the pipeline?
Arguably the biggest recent headline involved a UCLA pilot study that used PET scans and a radiotracer known as FDDNP to scan the brains of five living former NFL players in the hopes that they could detect the tau protein, which would mark the first time death and an autopsy weren’t required. FDDNP-PET imaging has previously been successful in visualizing Alzheimer’s in living patients, and in this pilot study, investigators reported that they believe they are detecting the tau deposits in the five subjects in the places where it collects. They did not find any in the five control subjects. This does not mean that it works; only that future trials have been justified and be planned and carried out using larger cohorts.
Why we’re all so up in arms about concussions at the professional level is beyond me anyway. This isn’t my job or your job. This is Donald Fehr’s job, the head of the Players’ Union and arguably the most powerful labor leader in North America. The man who can help shut down the game to enrich his membership can surely act in a meaningful way to make the game safer for them as well. This isn’t a public health issue, it’s an occupational one. Concussions are an occupational hazard for the pro hockey player, and a mild one at that all things considered. In 2007, home healthcare workers reported 27,400 injuries on the job, ranging from bloodborne pathogens to needlesticks, unhygienic conditions, verbal and physical abuse, guns, drugs, hostile animals and more. And they’re trying to help people. Each morning over 91,000 men and women in the United States head off to work in coal mines– mining the coal that feeds the electricity grid. About 25-30 die every year. Where’s that uproar?
If you absolutely must fly off the handle at every word of a concussion, do it for the kids playing sports in your town or school. They’re the ones who need a voice.
Benson et al. Is protective equipment useful in preventing concussion? A systematic review of the literature. Br J Sports Med 2009;43(Suppl 1):i56-67.
Biasca N et al. The avoidability of head and neck injuries in ice hockey: an historical review. Br J Sports Med 2002 Dec;36(6):410-27.
Daneshvar DH et al. The epidemiology of sports related concussion. Clin Sports Med. 2011 Jan;30(1):1-17, vii. doi: 10.1016/j.csm.2010.08.006. Review.
———-. Helmets and mouth guards: The role of personal equipment in preventing sport related concussions. Clin Sports Med 2011 Jan;30(1):145-63.
Giza CC, Hovda DA. The neurometabolic cascade of concussion. J Athl Train. 2001 Jul-Sep; 36(3): 228–235.
Jordan BD et al. Apoliproprotein E epsilon4 associated with chronic traumatic brain injury in boxing. JAMA 1997 Jul 9;278(2):136-40.
Martland HS. Punch Drunk. JAMA. 1928;91(15):1103-1107.
McKee AC et al. Chronic Traumatic Encephalopathy in Athletes: Progressive Tauopathy following Repetitive Head Injury. J Neuropathol Exp Neurol. 2009 July ; 68(7): 709–735. doi:10.1097/NEN.0b013e3181a9d503.
———-. The spectrum of disease in chronic traumatic encephalopathy. Brain. 2013 Jan;136(Pt 1):43-64.
Mueller FO, Cantu RC. Catastrophic sports injury research: Twenty-Sixth annual report. Fall 1982-Spring 2008, University of North Carolina, Chapel Hill.
Ryan AJ. Protecting the sportsman’s brain (concussion in sports). Br J Sports Med. 1991 June;25(2): 81—6.
Small GW et al. PET Scanning of Brain Tau in Retired National Football League Players: Preliminary Findings. Am J Geriatr Psychiatry. 2013 Feb;21(2):138-44.
Tegner Y, Lorentzon R. Concussion among Swedish elite ice hockey players. Br J Sports Med. 1996 Sep;30(3):251-5.