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What Is concussion? The Signs And Symptons

What is Concussion
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The movie Concussion, currently screening at your local picture palace, deals with NFL players’ catastrophic experience of the phenomenon. Actor Will Smith plays Bennet Omalu, the doctor who uncovers the truth about the damage to the brain concussions can cause. So if you play a vigorous contact sports and have ever seen the little birds and bells circling your head, pay closer attention…

What is concussion?

It’s sudden – but usually short-lived – loss of mental function that occurs after a blow or other injury to the head. Symptoms include headaches, dizziness, confusion, amnesia, balance problems, blurred vision, vomiting and nausea. According to the NHS it is the most common but least serious type of brain injury.

How is it different from having just “banged one’s head”?

Very different. Concussion is most often caused by being punched, kicked, whacked, smashed or crunched in the head. But it’s how the brain reacts that is the key – concussion occurs when the brain moves so much that it’s not protected by its cerebrospinal fluid, bruising the brain and/or damaging the brain’s pathways.

So you don’t have to be knocked out to get concussed?

No. In fact, as Dr Dominic Paviour, a consultant neurologist at St George’s University Hospital in London, tells Coach, “Concussion doesn’t necessarily correlate particularly well with the severity of a head injury. A minor bump on the head can cause it. A more significant clash of heads, with a loss of consciousness could cause it, but not always. And sometimes people with very severe head injuries, of the kind that leaves you unconscious for a longer period, don’t describe common concussion symptoms on recovery.”

But it’s always caused by a blow to the head, yes?

Not necessarily. As Dr Mike Loosemore from the English Institute of Sport (EIS) explains, “Sometimes when people jump off a high building and land on their feet they can get concussed because of the force impulse going through body and into their head gives them a concussion as well.”

So apart from parkour, which other sports may be more likely to lead to concussion?

Horse riding, rugby (union and league), skiing and snowboarding and American football. However, according to Loosemore, who also works with GB Boxing, says that boxing “comes quite a long way down the list”. “Boxing has about the same concussion rate as ice skating,” he says. “Because when you fall over in ice skating you hit a pretty solid floor.”

So should I stop my young sons playing rugby?

Not necessarily. But it is worth being aware of the risks. In 2013, for instance, the Auckland University of Technology examined every hit sustained by a single amateur rugby union team in New Zealand during a season by using a high-tech mouthguard, which measured the force of each hit and how much the brain moved afterwards. It found that over a 19-match season, the squad experienced 20,687 impacts to the head greater than 10g (roughly the impact of a light punch) – or an average of 77 impacts to the head per player-position per match.

And the take home from the study?

According to Doug King, one of the academics involved, “The research shows there are repetitive sub-concussive impacts to the head in rugby union. When compared with American football, in some cases these are higher in frequency.”

What do you mean by sub-concussive impacts?

These are the hits which aren’t severe enough to cause concussion but can still show up as bruising on a brain scan – and, researchers are finding, can possibly lead to lasting brain damage, if the brain is not allowed to heal through resting.

What about my weekly game of football?


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The chances of getting a concussion playing football are very slim. But interestingly, recent research suggests that repeated heading of modern lightweight footballs could have a greater impact on the brain than previously thought. Researchers at Purdue University in the US found that some of the forces generated by heading back goal-kicks were as high as between 50g and 100g – similar to American football players crashing into each other.

But could that really cause concussion?

No. But the Purdue study did find something else: that MRI scans on players who headed the ball frequently showed evidence of sub-concussive damage. With rest these bruises healed, just like any other bruise. But without rest the risk of a more serious injury increased. So it might be wise not to spend every day practising heading goal-kicks.

But context and balance is key, right?

Exactly. As Paviour points out, the chances of having a significant injury from playing an amateur sport such as football, rugby or tennis are low. “That goes for horse riding and skiing too,” he adds. “There may be a small risk, but if it happens to you it is potentially catastrophic. Anecdotally, I have a neurologist friend who has two boys and he will let them play soccer but not rugby. He doesn’t think it is worth the risk.”

When should you see a doctor?

If you take a hit on the head and don’t feel right. As Paviour explains, the symptoms could include not liking light or loud noise, feeling an inner fogginess, headaches, nausea, feeling tearful or over-emotional or depressed. “Any one of those things could indicate concussion,” he says.

Is it easily misdiagnosed?

Not by a professional. But during a match a player might be told to “run it off” rather than sit out on the sidelines, which could be inviting trouble.

So is there a risk of more damage if you play on through a concussion?

“For me that’s the biggest worry,” says Loosemore. “If you go on concussed you are not thinking as clearly, you are not moving as clearly and you’re more likely to get hurt. And the next time you might get hurt a lot more. There’s certainly good evidence that when you get concussed again while concussed, it takes much longer to get over it a second time.”

How long does concussion take to recover from?

Usually 90% of people get better in a week, and 99% get better in a month – providing they physically and mentally rest until the symptoms disappear. “Mental rest is often the hardest thing because that means no watching TV, no playing Grand Theft Auto, and no reading books or newspapers,” warns Loosemore. “It’s actually very boring. It could go on for a few days. If it went for longer than a couple of weeks I’d start to look at other causes for the symptoms.”

Should we just wear a helmet for everything, then?

No, says Loosemore, who also founded the Centre for Health and Human Performance (CHHP).

“Clearly there are some sports in which should wear a helmet. If you are horse riding or motorcycling – where your head is in danger of forcefully hitting a very hard surface – then you want a hard outer shell to protect your skull from fracturing. But the crucial thing is this: a helmet isn’t effective in stopping a concussion. Because, as we know from decades of research, your brain is still going to move inside your skull regardless of whether you wear a helmet or not. Your helmet could be made of titanium and that wouldn’t change.

“Look at the NFL. The risk of concussion remains high even though they wear helmets. The same with rugby, even though more players wear skull caps these days. It’s also worth remembering that when doctors forced the authorities to put headguards on boxers in 1984 for the Los Angeles Olympics, the number of knockouts increased by three times. It actually increased injuries – the opposite of what they wanted to achieve. And since removing helmets from amateur boxing in the past couple of years, what has happened? The number of concussions have reduced by 20%.

“My view is that a helmet gives you a false sense of security and an increased sense of bravado. So players put their head where you shouldn’t be because they are less worried about taking a blow. Yet those impacts to the brain still cause damage. And that damage can lead to concussion.”

– Sean Ingle