Wonder Woman is arguably the most powerful hero in the DC Universe, despite her relatively smaller size compared to Superman, Batman, and beyond. Just as the dangerous power and potential of superheroes come in all sizes and shapes, it is dangerous to assume all concussions are created equal. No matter who you are or what biological sex or gender you identify with, when you are engaged in contact sport you are exposed to concussion risk. Concussion, or to use the accidentally dismissive yet commonly applied term of “mild traumatic brain injury,” requires individualized management given the multiple aspects influencing treatment and recovery.
Just like Wonder Woman's powers, abilities, and challenges, studies have been showing that men and women present significant differences at all levels of concussion management, from exposure to recovery. But just as almost all major superheroes have been men, research studies have been typically done with men only. There is a huge gap in understanding related to women. But that’s probably fine, right? Women have mostly been neglected as participants in physiological research since, well, pretty much the very beginning. Instead, it seems women are often just thought of as slightly smaller versions of men, which is, of course, incorrect. Differences due to sex and gender must be carefully addressed when it comes to health. It is simply part of the process of understanding variability instead of the search for universals.
Women have unique challenges and an uphill battle against concussion. Source: E. Paul Zehr While women are generally healthier and have a longer life expectancy than men in North America, women are more susceptible to certain health conditions. These include stroke, osteoarthritis, and mental health issues like depression and anxiety. While both have been neglected, a clear example where women need a specific approach is concussion in combat sports.
Bruno Follmer, a Ph.D. trainee at the University of Victoria, Rodolfo Andre Dellagrana from Federal University of Santa Catarina in Brazil, and I analyzed almost 2000 MMA fight outcomes from Ultimate Fighting Championship (UFC) bouts. Our study was the first to differentiate head trauma exposure for men and women in MMA and what we found was stunning.
Source: Courtesy Pixabay. The incidence of a fight ending due to head strikes was compared across the male and female weight categories. We showed that fights in the female bantamweight division (56.7 to 61.2kg) had a 221% increased risk compared to the strawweight (up to 52.1kg).
For the female weight categories, there is about a 9kg difference between the upper limit weights for bantamweight and strawweight. To find a similar ~200% increased risk in men the weight difference was more than 5 times larger (50kg) and contrasted heavyweights (up to 120kg) compared to the lightweights (up to 70.3kg). This adds to the recurring technical mismatch in some fights with women, such as the recent boxing match that resulted in a gruesome 7-second knockout.
When studied in laboratory conditions of acceleration mimicking whole body impacts, women have higher acceleration and larger displacement in the head-neck segment than men. This is important because muscles surrounding the neck can decrease acceleration and, therefore, the forces that are transmitted to the brain. Also, during baseline assessment after concussive impact exposure, women often endorse more symptoms, and at a higher severity than do men. This makes the concussion diagnosis more difficult and suggests additional approaches are needed.
The recovery process after a concussion seems to take longer in women. Evidence suggests more persistent disruption in executive function (like paying attention, planning, focusing, and regulating emotions) and in the autonomic nervous system (involuntary actions) in women. Migraine and visual memory impairment are also particularly common in women. The issue becomes even more dangerous in multiple episodes because female athletes with a history of concussions can have reduced cerebral blood flow compared to women with only one concussion, a result that was not found in men.
THE BASICS
Source: Courtesy Pixabay Despite efforts to include a more explicit study of women in all domains, a huge gap remains in concussion research and clinical practice. A recently published review exploring neurological consequences of repetitive head impacts analyzed studies from 1930 up to the 2000s. In this comprehensive summary, not a single case involving female athletes was described.
Beyond the poor representation in superhero movies, women have been neglected in science and medicine. This neglect has huge negative implications for health and wellness. Using the explicit example here, the dismissive attitude that women are just little men when it comes to concussion management has to be forcefully refuted. The increase in female participation in fighting sports, and the recent female superhero empowerment movies (including both Wonder Woman and Wonder Woman 1984) are reasons to believe that the media exposure and cultural recognition is growing. Scientific exploration and medical management must continue to match and support the real difference between women and men.
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Concussions Among College Students Warrant Greater Attention Note: This post was a collaboration with Bruno Follmer, a Ph.D. candidate in the Rehabilitation Neuroscience Laboratory at the University of Victoria, and Aaron Alexander Varga, a medical student at the University of Alberta.
© E. Paul Zehr (2020)