Differences between the male and female brain have been the subject of extensive research for decades. Although difficult to study, research has shown that being XY vs. XX can correlate to differences in how you think, feel and even respond in a given situation.
But did you know that males and females may also differ when it comes to concussion injuries?
Recent research suggests females may be more susceptible to sustaining concussion injuries than males, and if they do, they may take longer to recover.
First, let’s dig deeper regarding the susceptibility of concussion.
It has been established in many studies that, in sports where both sexes participate, girls tend to have a higher incidence of concussion than boys. One study found that female high school athletes are 1.56x more likely to sustain a sports-related concussion than their male counterparts playing the equivalent sport (1).
A systematic review by Prien et al. (2018), found that women’s ice hockey ranked third (behind only men’s rugby and men’s football) for the highest concussion rates during game play (2). This was ahead of men’s hockey which is a full contact version of the same game. Another study also found that girl’s soccer had the highest incidence of concussion of all high schools sports (3). Even higher than boys football! There certainly looks to be a sex difference in regards to susceptibility.
Recently, a large meta-analysis was published that examined sex-differences in the incidence of sports-related concussion(4). Meta-analyses are particularly useful because they combine all previous studies into one – a summary of sorts. This particular meta-analysis examined various ages and sports (contact & non-contact) and found that with both soccer and basketball, there was a significantly higher incidence of concussion in females compared to males. There were no significant differences found between girls and boys with hockey and lacrosse.
Why the difference with some sports and not with others?
One reason may be the involvement of contact during game play. Soccer and basketball both have similar levels of contact between the sexes and females appear to sustain more concussions. Whereas with hockey and lacrosse, men engage in significantly more contact than women and this may increase the incidence of concussion among the males in these sports. Even still, it only puts them equal to females in terms of concussion risk.
So it seems that girls really do get more concussions than boys – but does this mean that girls are actually more susceptible to concussions?
There are several theories as to why girls may get more concussions than boys but only two of them deal with increased susceptibility. Here are the theories:
- Hormonal fluctuations – Hormone fluctuations throughout the menstrual cycle are thought to potentially increase the susceptibility of women to concussions, although this theory has not yet been widely studied.
- Differences in neck strength – females generally have decreased head-neck strength compared to males and tend to go through greater peak acceleration and increased angular displacement during impact than males. This theoretically makes females more likely to sustain the acceleration/deceleration force required to produce a concussion in the first place.
- Reporting differences – some researchers suggest that females may simply be “more honest” than males leading to increased relative reporting of these injuries for females in sport.
In addition to differences in susceptibility, studies also indicate that once concussed, the recovery trajectory may be longer in females than males.
Theories as to why this may be are similar to those with injury susceptibility.
Preliminary studies have found that women who sustained concussions in the 2 weeks prior to menstruation (luteal phase) had slower recovery than women who were concussed in the 2 weeks directly after their period or women taking the birth control pill.
Also, females generally have a reduced head to neck ratio compared to males, which may lead to more acceleration, potentially a more severe injury, and therefore longer recovery.
Other theories include women taking more time to present for care (increasing the chance for chronicity) and the tendency for male sports to have more funding and perhaps better sideline medical personnel and post-concussion care.
Although these theories warrant further investigation, the preliminary findings are interesting nonetheless! Understanding this area better will affect how healthcare practitioners treat and manage concussions across the two sexes.
If you’d like to learn more about these interesting sex differences, watch this recent video podcast on the topic:
- Bretzin AC, Covassin T, Fox ME, Petit KM, Savage JL, Walker LF, et al. Sex Differences in the Clinical Incidence of Concussions, Missed School Days, and Time Loss in High School Student-Athletes: Part 1. The American Journal of Sports Medicine. 2nd ed. 2018 May 23;46(9):2263–9.
- Prien A, Grafe A, Rössler R, Junge A, Verhagen E. Epidemiology of Head Injuries Focusing on Concussions in Team Contact Sports: A Systematic Review. Sports Medicine. 2018 Jan 18;48(4):953–69.
- Schallmo MS, Weiner JA, Hsu WK. Sport and Sex-Specific Reporting Trends in the Epidemiology of Concussions Sustained by High School Athletes. J Bone Joint Surg Am. 2017 Aug;99(15):1314–20.
- Cheng J, Ammerman B, Santiago K, Jivanelli B, Lin E, Casey E, et al. Sex-Based Differences in the Incidence of Sports-Related Concussion: Systematic Review and Meta-analysis. Sports Health: A Multidisciplinary Approach. 2019 Sep 30;53(2):194173811987718–6.