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Concussions: What We Know and What We Don't

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Concussions: What We Know and What We Don't

Dec 22, 2015

It might surprise you, but doctors’ understanding of concussions is still in its infancy. In this podcast, we ask neurosurgeon Dr. Greg Hawryluk to bring us up to speed on what we know and what we don’t. He also clears up some misconceptions, talks about how they affect the brain, and what should worry you the most if you get a concussion. There is one thing we know for sure: If you think you have suffered from a concussion, it’s important that you see a doctor.

Episode Transcript

Interviewer: Are concussions more serious than people think? We'll find out next on The Scope.

Announcer: Medical news and research from University of Utah physicians and specialists you can use for a happier and healthier life. You're listening to The Scope.

Interviewer: Dr. Greg Hawryluk is a neurosurgeon at University of Utah Healthcare. It seems like there's a lot in the news and in popular culture about concussions nowadays, and we're starting to learn that maybe they're a little bit more serious than we first thought. It feels as though at one point, if you got a concussions somebody would go, "How many fingers am I holding up?" If you passed the test, great. You're okay. But it's a little bit more serious than that, we're starting to learn.

Dr. Hawryluk: That's exactly the case. First off, what I can tell you is that it's probably an epidemic. There's probably way more concussion out there than we've ever really known. We're only now starting to see a lot of people coming to doctors with their concussion.

Interviewer: So how serious is a concussion in terms of the damage caused to the brain?

Dr. Hawryluk: The problem there is that we really don't know. We don't think that a concussion implies a structural injury to the brain. We still think that it's probably sort of a chemical imbalance. But there's no question that we do think it puts you at risk for ongoing damage to the brain, perhaps over the rest of your life. We are seeing something we call chronic traumatic encephalopathy, changes consistent with Alzheimer's disease in the brain. It really is suggesting that athletes need to be a lot more careful in terms of avoiding concussions and having them treated by a doctor, than has been the case in the past.

Interviewer: So a concussion is when your brain actually hits your skull. Right? So it's not a physical bruise in terms of like what a muscle is. But it causes a chemical imbalance. Explain that.

Dr. Hawryluk: Yeah. There's a few misconceptions about concussion. So one is that you don't actually have to hit your head to have a concussion, and you don't have to lose consciousness. Really, all that has to happen is your brain sloshes around inside your skull. The hallmark is that there's at least a temporary change in brain function. But in fact, we don't see bruising of the brain. We think that probably it's a chemical imbalance that leads to the brain dysfunction. If it gets to the point where there's actually bleeding in or around the brain that is an even more serious condition.

Interviewer: What does that chemical imbalance look like? What's going on there?

Dr. Hawryluk: It's something we really don't understand. It's something that's hard to study. What's really funny to me as both a neurosurgeon and as a scientist is that we haven't made more progress in this field. We can put people on the moon, but we really don't understand what's going on. In some senses, we're sort of at square one with concussion. The important thing is that we're recognizing the significance of it. But there's an awful lot more work to do to figure out what's going on and how to best treat these.

Interviewer: If I understand correctly, a single incident can be bad, can cause symptoms and damage. But it's the multiple incidents without recovery time that you're really worried about.

Dr. Hawryluk: Well, that's absolutely true. We're concerned about both cases. One concussion is certainly a concern and has to be appropriately treated. These days, we certainly advise that every concussion should be seen by a doctor. But our level of concern as physicians goes up quite a bit when we start to see multiple concussions. The worst case scenario that we worry about as doctors is basically a repeat head injury before the first concussion is fully resolved.
The reason that that's so important is because we actually see people die from that. There's something called "second impact syndrome." So if a player, for instance, goes back to playing football before their first concussion is resolved, some of those patients have died. We know that there's a tremendous amount of brain swelling that can occur in that instance, and that's one of the biggest things that we're trying to avoid and get word out to both players and coaches. That once you've had a concussion, you need to sit out and be seen by a doctor.

Interviewer: Outside of football is that the case, say for example, I was skiing and took a hard hit and got a concussion. Could the same thing happen if I got a second concussion as a football player?

Dr. Hawryluk: That's absolutely the case. One of the challenges with concussion is that a lot more things can cause concussion than I think a lot of people realize. Football is one that we would all think of. But I always tell people, I remember a time when I was younger and when I was on a roller-coaster, and I'm pretty sure I had a concussion on that roller-coaster. So, really anytime that you're jarring your head around that's a big issue.

Interviewer: If I get that one-time concussion, whether I'm playing a sport or in an accident, or something like that, should I be super-concerned above and beyond seeing a doctor?

Dr. Hawryluk: Well, the biggest thing is to see a doctor. The biggest change of concussion management over the last 10 years has been the idea of rest and graduated return to normal activities. We do think that we've learned that that leads to the best recovery from a concussion. After any sort of a concussion, the minimum amount of time it takes to fully get back to what you were doing before in terms of activities is about a week.
Some recommendations say that in children it should probably take twice that long to get back to normal activities. So, that needs to be medically supervised. There's usually six steps that we talk about as people go back to their normal activities. The good news with concussion is that the vast majority of people have a resolution of their symptoms and ultimately do quite well. There are, however, a minority of patients, maybe 20% that even six weeks out from a concussion are still having trouble, something we call "post-concussion syndrome." But the good news is that fortunately that's a minority of people.

Interviewer: Are there long-term repercussions to concussions then?

Dr. Hawryluk: Well, there certainly can be. So we think that at some level there is a brain injury, and we certainly worry about the accumulative effects. We are starting to learn, again with these professional athletes that perhaps these seemingly minor blows to the head when they're accumulative can lead to depression and behavior change. In fact, we think that maybe even some suicides have been linked to this.

Interviewer: Which comes back to that chemical imbalance [inaudible 00:06:16].

Dr. Hawryluk: That's exactly right.

Interviewer: That makes total sense.

Dr. Hawryluk: Yep.

Interviewer: What's the future hold? What do you think we're going to find in the next 5, 10 years? You said it's in its infancy. Where are things going?

Dr. Hawryluk: Yeah. It's a time where the concussion field is advancing in a lot of different directions. We're learning more and more about the basic science of the condition. We're learning more about how to treat these patients and how to manage them in terms of their sporting activities.
One of the things that is something I think an awful lot about is people that are participating in contact sports. I'm hearing a lot of parents these days with reservations about having their children play hockey or football. I think to a certain extent that's reasonable. But if I look back on my own life, the lessons that I learned playing sports with other kids is so important for socialization and it's important to be active and to be healthy.
So I just have a bit of concern that the way this conversation seems to be going is should kids be participating in some of these sports? What I always counsel my patients and their families is that I really think participation in sports have so many benefits that I hate to see kids pulled out. I think really what's important is encouraging safe play. The reality is that most concussions we think are probably preventable. Teaching players to treat each other with respect, to obey various rules for safety, I think those are the key. Again, I just worry about kids not participating because of some of these fears.

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