Concussion in Sport – What are the Risks?

Concussion has again been in the media spotlight with a number of high profile rugby players taking out a class action against World Rugby. This suit seems likely to grow and to include former Kiwi players. Given the frequent reporting about concussion in the media, and the sometimes-conflicting reports, it can be hard to understand what the actual risks are with playing contact sport. This article aims to summarise the evidence and give some practical recommendations about choosing a sport for your kids.

Long-term consequences

There is an increasing body of evidence that there may be some long-term consequences associated with head injuries sustained while playing sport. It is however important to acknowledge that there is currently no study that shows a definitive link between concussion and long-term brain injury. There are two studies that are often discussed in reference to this in the media. The first study involved the post-mortem assessment of the brains of ex-NFL players. This showed that almost all of the brains had evidence of chronic traumatic encephalopathy (CTE). One of the major issues with this study though is that all of the brains in this study were donated by players who had already experienced neurological symptoms. As a result, it is perhaps not a surprise that these players had abnormal findings. What remains unknown is what the brains of players with no symptoms looked like. The second study involves comparing ex-professional footballers from Scotland with a control group of non-football players. What has been widely reported in the media is that the footballers have a three times increased risk of dying from a neurological condition (like dementia or Parkinson’s disease. What has not been so widely reported though is that the footballers had better health outcomes (for example less cardiovascular disease) and lived longer. This increased longevity may be one reason why they were more likely to develop dementia.

Heading, tackling and other head impacts

While a concussion is relatively rare, most players who play a football code experience a number of relatively modest impacts to their head during any given training session or match (think heading in football). It is proposed that these impacts might, over time, increase the risk of long-term issues with the brain. While there are some studies that have shown that these activities might have some short-term effects on memory and brain function there are currently no long-term studies that show that these actions are dangerous. This is highlighted by a recent meta-analysis (a study that pools all the available data) looking at the effects of heading. This study concluded that there was no evidence that heading was dangerous. The study discussed above (in Scottish professional footballers) showed that there was no difference between goalkeepers, who head the ball rarely, and outfield players in terms of the risk of developing a neurologic condition. This may also suggest that heading may be less relevant.

What sport is best?

It is important to consider both the sport and the number of training sessions and matches when considering the risk of injury. The incidence of concussion is reported to be approximately three times higher in rugby and rugby league (than in football and other sporting codes). It is however important to recognise that kids who participate in football often have multiple training sessions and games per week. This effectively increases their number of ‘exposures’. For example, if a football player has three times as many training sessions a week (compared with a rugby player) their absolute risk of concussion is going to be similar. Combat sports, like boxing and MMA, have a very high risk of head injury.

What about ‘playing’?

While much is made about the risk of concussion associated with playing organised sport we should not forget that there is a degree of risk associated with day-to-day life, playing and from other activities (like riding a bike). It is hard to quantify this risk however it seems likely that the risk posed by many of these activities may be similar to those posed by unorganised ‘play’. It should be noted that the majority of hospital admissions due to head injuries in children do not occur from footballing codes and are more frequently associated with general play, bike-riding and incidents outside of sport.

So what would you do..?

My own personal view is that we will over time find that there is a link between concussions and longer-term cognitive problems. I think that it is likely that there are some individual traits that will predispose to future problems and that the risk will be enhanced with an increasing number of injuries and exposure. That said I believe that playing sport has overwhelming health benefits and I am not unduly concerned about the burden of concussion.

I would be comfortable with my kids (I have three boys) playing any football code under the current rules. I would, however, be very uncomfortable with them participating in combat sports (as the primary goal of these sports is to inflict a head injury). I would be more concerned however if they did sustain a concussion. I would be quite conservative with their treatment and return to sport. If they then went on to sustain multiple concussions I would encourage them to take up tennis.