Concussions are common in contact sports but in recent years, there has been a growth of litigation against professional governing bodies for compensation, alleging negligence in not taking reasonable steps to protect players from injury caused by repetitive concussive and sub concussive blows.

Concussions are brain injuries and can affect athletes at every level from amateurs to professional sports men and women.

Common symptoms of concussion in the short term are confusion, headaches, vomiting and speech problems but there are medical experts who suggest that in the longer term, repeated concussions are linked to early onset dementia and similar disorders such as Parkinson’s disease and chronic traumatic encephalopathy (CTE).

Medical causation will be difficult to prove in respect of these claims that repeated concussion could cause early onset dementia because there are numerous factors that increase the likelihood of any one person to develop dementia, such as genetics, age, sex, weight, alcohol use, level of fitness, diabetes, education, diet, and other lifestyle factors.

There are over a million people in the UK living with dementia and 1 in 20 people in their late 60s will have dementia or similar, and this number increases with age so that over half the people living into their 90s will have dementia. Dementia is a progressive degenerative condition that causes cognitive and physical disabilities.

The controversial issue of the link between one traumatic brain injury and early onset dementia has been tested in the leading high court case of Mathieu v Hinds in April 2022. The court was not satisfied that research presented a causative link between a one-off head injury and early onset dementia. In that case, the claimant was seeking a provisional damages order for the risk of early onset dementia.

The current litigation seeks to link recurrent concussion to early onset dementia and is of course different in a number of respects. Here, the athletes are trying to persuade the court that the respective bodies were negligent in not taking steps to reduce the risks posed by the sport and that there is a causative link between recurrent head injuries and early onset dementia. This issue of recurrent head injuries and the link to early onset dementia has yet to be tested in court but there are significant medical causation difficulties for those bringing these types of claims. 

Former Wales rugby Captain, Ryan Jones, and England’s world cup winning hooker, Steve Thompson, are among the group of professional and semi-professional players involved in a class action of more than 185 rugby union players in their 30s, 40s and 50s, being brought against several professional bodies including World Rugby, Rugby Football Union, and Welsh Rugby Union. This litigation is on-going and is the first of its kind in England and Wales.

The first ever UK wide concussion guidelines for grassroots sport were published by the government and Sports and Recreation Alliance in April 2023 aiming to help identify, manage, and prevent concussions in all types and levels of sport.

One issue that has gathered a lot of attention in the news recently is whether women are more susceptible to concussion in sport and whether they have more prolonged symptoms.

A 2021 US study found that teenage girls who play football were almost twice at risk of concussion as teenage boys, with girls more likely to be concussed on impact with the ball or goalpost.

Studies from US collegiate sports have shown that female athletes are 1.9 times more likely to develop a sports-related concussion than their male counter parts in comparable sports. Not only are they more prone to concussion, but their symptoms tend to be more severe, and their recovery time is longer.

Researchers point to several factors that may predispose women to greater effects of concussion including the girth of the female neck being 30% smaller than males, which increases the potential acceleration of the head by as much as 50%. There are also anatomical differences within the brain itself. Female brains are thought to have slightly faster metabolisms than male ones, with greater flow of blood to the head. Thirdly, there is evidence that the effects of concussion changes with varying hormone levels during a woman’s menstrual cycle.  

World Rugby has made a commitment to funding equal men and women’s research. Smart mouthguards are used in professional rugby to monitor in-game head impacts whilst scientists behind a ground breaking saliva test, where a swab is taken to look at markers of how the brain is functioning, have extended their study into women’s rugby.

FIFA has funded a research project at the Institute of Sport Exercise and Health in London, to focus on the impact of heading the ball in relation to women’s brain health.

Given that many more women are taking up contact sports like rugby and football, that might put them at greater risk of injury, it is likely that more research will be done to explore not only the effects of concussion on women but the reasons for the greater effect on them. A better understanding of the factors involved could lead to better prevention and care.


Emma Eccles is a Partner in the national catastrophic injury team at Clyde & Co and a member of the brain injury subject matter group.

Emma produced a podcast in 2023 with her colleague Helen Kanczes and neurologist, Dougall McCorry to discuss the case of Mathieu and one-off brain injuries and the alleged link to early onset dementia, exploring the difficulties in the diagnosis of dementia, risk factors, current research available and its limitation and a best practice guide for insurer clients.