Could the ‘notch’ be key to understanding ACL injuries in women’s football?

Players who compete in the top two levels of German women’s football are four times more likely to rupture their anterior cruciate ligament (ACL) than their male counterparts, according to the German Football Association (DFB).

The governing body has funded a central injury and illness registry in women’s football for three years. So far in the Frauen Bundesliga , Germany’s top flight, there have been a reported seven ACL injuries 10 games into the current campaign. In the men’s Bundesliga , meanwhile, there have been three such injuries.

Among those to have suffered the injury is the Bayern Munich midfielder Lena Oberdorf . The Germany international recovered from an ACL injury to start this season and played six matches before rupturing the same ligament in the same knee. The DFB has implemented several measures to try to limit the amount of ACL injuries sustained by male and female players, including “training formats for medical staff and content on injury prevention in coach education” and “a scientifically supervised test battery with individual training recommendations”.

ACL injuries are prevalent across the women’s game with a reported seven players enduring one in England’s Women’s Super League already this season. Among them is Michelle Agyemang , who ruptured an ACL during England’s 3-0 friendly win over Australia last month. And according to ACL Women Football Club, a social media account that collates information on the injuries in the sport via research and club announcements, France’s Première Ligue has recorded six ACL issues and Italy’s Serie A Femminile two so far this season. None have been recorded in Spain’s Liga F.

ACL injuries have become more common in the women’s game than in the men’s, leading to studies into the reasons. Fifa is funding research into discovering if hormonal changes impact the likelihood of the injury occurring in women.

Saket Tibrewal is a consultant trauma and orthopaedic knee surgeon at Cromwell hospital in London. He conducts three to four ACL surgeries a week and says medical professionals do not yet have answers regarding the higher rate among female players.

“We are still in the infancy of really understanding this,” Tibrewal said. “I think the reason for that is women’s football has exploded on a professional level over the last few years. Five years ago there were probably the same amount of injuries but people weren’t aware of it. I think that it is now so much more mainstream we are seeing it a lot more.

“The biomechanics of women are very different to men, in terms of muscle strength and landing mechanics. Women’s bone anatomy is also smaller than men’s. Where the ACL goes in, it is in the middle of the knee; we call it the notch. Women seem to have smaller notches; is that a reason to cause impediment or [more] force through it? We don’t know, but it’s something we are looking at.”

The Chelsea and England midfielder Keira Walsh recently said the increasingly busy schedule that female players have to adhere to could be another factor. “Maybe sometimes we do play too many games in a congested fixture schedule. There’s not enough recovery time,” said Walsh. “You can do the research, but ultimately you need to listen to the ones going through it and how we can best find the solutions.”

With women footballers rupturing ACLs at such a high rate, what does the future hold for limiting the injury? “We are going to know a lot more in the next five years, which will hopefully push us on even further,” said Tibrewal. “If players do get ACL injuries, we are better now at getting players back to a very high level. We are on an upward curve on getting excellent outcomes from these surgeries. Watch this space to where we go next with it.”

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