Soccer is a contact game. Players collide in the fight for the ball, fall and injure themselves. Just like Christoph Kramer in the final game of the 2014 World Cup. Kramer hit his head in a duel and looked disoriented, but continued to play until he couldn’t do it anymore. Only later did it turn out that he had suffered a concussion. The Kramer case is one of the best known, but not an isolated case.
The world football association Fifa has now reacted. At the current women’s soccer World Cup, so-called “concussion spotters” are now observing the games for the first time and keeping an eye out for possible concussions. If there is any suspicion, they notify the medical staff. An overview of what makes concussions so dangerous and why women especially benefit from the new “scouts”.
A concussion is caused by a head injury, such as collisions and falls while playing sports. It is also known as mild traumatic brain injury. The violent effect on the head leads to “a mostly short but sometimes longer-lasting functional disorder or neurological disorder of the brain”, as can be read in a recommendation for action by the Federal Institute for Sports Science on craniocerebral trauma. To put it simply, “the concussion leads to a smaller or larger short circuit in the normally ordered jumble of nerve cells and electrical lines [in the brain]. Connections between individual nerve cells can be torn off.”
Symptoms usually appear soon after the injury, but it can take up to 48 hours. Typical symptoms include headaches, memory problems, nausea, vomiting, and drowsiness. “The cause of the typical symptoms of a concussion is mechanical irritation of the nerve fibers, which can be accompanied by a temporary loss of function,” explain the neurologists and psychiatrists in the network.
Head injuries should always be examined by an (emergency) doctor; in the case of a concussion, monitoring usually lasts 24 hours. This is important because traumatic brain injury can result in cerebral hemorrhage and contusion. After a concussion, a physical and mental rest period of one to two days is important. A concussion usually heals completely within a few days. But not always.
As a rule, the symptoms subside completely and the brain recovers completely. “But not for up to 30 percent of those affected, which is why they are called the ‘miserable minority’. They can have symptoms such as headaches, concentration and sleep disorders, depressive moods for months or years,” says Inga Koerte, Professor of Neurobiology.
A study carried out by the University of Nottingham on behalf of the Football Association of England and the Professional Footballers’ Association found that professional footballers were almost three and a half times more likely to develop dementia or another neurodegenerative disease such as Alzheimer’s in the general population (2.8 percent/0.9 percent).
Scientists currently assume that chronic traumatic encephalopathy (CTE), also known as boxer’s disease, is caused, among other things, by repeated head injuries such as hits or bumps. CTE is a neurodegenerative disease in which nerve cells die. Symptoms include dementia, depression, suicidality. The disease has now been detected in hundreds of professional athletes, including football professionals.
According to the Federal Institute for Sports Science, 270,000 people suffer a craniocerebral injury in Germany every year, the majority can therefore be classified as minor. There are currently no valid numbers specifically for concussion. It is assumed that 40,000 to 120,000 concussions are treated in emergency rooms in this country. At least 44,000 people have sustained concussions while playing sports, with undocumented cases estimated to be “much higher.” “Especially in contact sports, 5 to 15 percent concussions can be expected in relation to all injuries suffered,” according to the Federal Institute for Sports Science.
It is not clear how often women suffer brain injuries during sport. As is so often the case, there is a “gender data gap” with regard to such studies . This means that they are mainly conducted among male athletes. Female athletes are more likely to suffer from such injuries. The American Academy of Neurology reported in 2017 that female athletes are 50 percent more likely to suffer a concussion than male athletes playing sports like soccer.
Fifa’s “Health and Fitness for Female Footballers” guide states that women suffer more head and knee ligament injuries than men. According to this, 17 percent of injuries to female soccer players are to the head. As part of a small study by the youth development center for juniors at the Julius-Maximilians-Universität Würzburg (JMU), 127 female soccer players of junior age were asked about their injury histories. It was about athletes, the second to fourth women’s leagues. Every sixth player reported a concussion as a first or second injury.
Inga Koerte is a professor of neurobiology at the Ludwig Maximilians University in Munich and the Harvard Medical School in Boston. She is considered a luminary when it comes to head injuries. In the LMU research magazine “Insights”, Koerte explains that a study was able to show “that more changes in the brain can be detected in women after repeated head shaking”. Studies have also suggested that the symptoms women experience as a result of concussion are also more severe, more varied, and longer lasting than those experienced by men. Accordingly, women were more likely to show behavioral symptoms and more frequently reported difficulties in maintaining relationships. In men, it is more about neurological symptoms such as headaches or dizziness, she continued in an interview with “Süddeutsche Zeitung”.
The reasons for this are diverse. Hormones are probably one of them. A study by the University of Rochester indicates that the consequences of a concussion are also influenced by the phase of the menstrual cycle the woman is in. For example, women are “worse together” after a concussion and need longer to recover if the concussion occurred in the second half of the cycle, according to Koerte in “Insights”. According to the study, hormonal contraceptives could be a proven antidote. According to the neurobiologist, in addition to hormonal differences, factors such as genetic differences and differences in injury patterns also played a role.
The brain structure itself could also make a difference. “The axons, i.e. the extensions of the nerve cells in the brain, are thinner and less stable in women. If you pull on the axons, they tear faster in women than in men,” explains Koerte in an interview with “Spiegel”. So it’s possible that head injuries, such as bumps, not only cause concussions more quickly in women, but also have more serious effects on the brain. In addition, women’s brains work differently than men’s, so the two halves of the brain communicate more with each other. In the case of craniocerebral trauma, however, this connection is often damaged.
Further studies indicate that the physical constitution could also play a role. According to this, male athletes could have stabilized their neck better in comparison to female athletes. According to the conclusion of the study, targeted training of the neck area can reduce the risk of injury in women.
As part of a small study, Koerte and colleagues at the Ludwig-Maximilians-Universität in Munich and the Harvard Medical School investigated whether headballs, i.e. rather mild head concussions, are harmful to the brain. This was examined on the brains of twelve football professionals from a large club. The research team was able to prove, among other things, that “changes in the brain can also occur without acute symptoms,” as Koerte explained to “Die Zeit”.
The researchers found large-scale changes, especially in the areas responsible for memory and attention, among other things. “We found increased diffusion, which can indicate thinner myelin sheaths. If they become thinner, the conduction is not as fast. That could explain why brain functions deteriorate,” says Koerte. She hopes that this will also increase awareness of possible brain damage through sport in Germany. First steps have been taken. In March 2023, the professional clubs of the first and second Bundesliga signed a uniform protocol for dealing with head injuries suffered by players in German professional football.
Source: Neurologists and psychiatrists online, IQWiG, Gesund.bund, Federal Institute for Sports Science, study by the University of Nottingham, LMU, Süddeutsche Zeitung, University of Rochester, Spiegel, Science Information Service, FIFA, UEFA, Die Zeit, SRF, DFL brochure on head injuries
