DEEP DIVE: ACL Injuries in Women’s Football

With the news that Leah Williamson will miss the remainder of the 2022/23 season and this summer’s highly anticipated Women’s World Cup, I decided to take a deeper look into the history of ruptured anterior cruciate ligaments within the women’s game – and what can change to reduce the devastating impact of the injury. But first, let’s get up to speed on the basics.

What is an ACL?

An ACL – or anterior cruciate ligament – is the ligament that joins the femur to the tibia. It is crucial to knee stability and allows you to pivot more easily, which is a fundamental ability to have in a sport like football. The ACL isn’t the only ligament involved though – the Posterior Cruciate Ligament, Lateral Collateral Ligament and Medial Collateral Ligament are all just as important to the knee’s function.

However, it is the ACL that is most likely to rupture due to the excessive strain it faces when carrying out a sporting activity. Anterior Cruciate Ligament injuries are ranked according to a grading scale – where 1 represents an overstretched ACL, while 3 is a fully ruptured ligament. Based on the limited information we have surrounding Leah Williamson’s injury, it sounds as if the England captain has sustained a Grade 3 ACL rupture.

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What causes an ACL injury?

ACL injuries are caused by a variety of things – including twisting awkwardly and putting extra strain on the ligament. Quick changes of direction, rapid acceleration and sudden deceleration are also key causes. You can rupture your ACL after colliding with another player for example, though it appears Leah Williamson’s injury was caused by an overextension of the knee. The actual rupture of the ligament occurs within 70 milliseconds!

The most severe ACL injuries are often accompanied by a loud popping sound, which is actually the sound of the ligament tearing. The knee will be noticeably less stable, though some people are able to still walk following an ACL tear due to adrenaline.

How are injuries treated?

ACL injuries are treated according to their severity. Grade 1 injuries may just require physiotherapy, while Grade 3 injuries often require surgery – followed by a lengthy period of physio and rehabilitation work. Arsenal have confirmed that Leah Williamson will undergo surgery in the coming weeks, but the defender could still be looking at up to a year on the sidelines before she is fit enough to return to match action.


Now that we’ve got the basics out of the way, let’s take a deeper dive into the specifics of ACL injuries within women’s football. There are additional factors that need to be taken into consideration when compared to the men’s game, and some of the statistics we’ve discovered are truly mindblowing. Studies show that elite female athletes are up to six times more likely to sustain an ACL injury than their male counterparts.

Biological Reasons

Women have an entirely different hip structure to men. It is commonly reported that women have wider hips – though what actually seems to be relevant is the hip-to-femur ratio, which is greater in women. This increases the angle between the hip joint and the knee, placing extra stress on the anterior cruciate ligament.

Furthermore, hormones come into play as levels of LH and FSH rise during ovulation. This appears to allow more travel within the knee joint as it loosens and becomes lax – which in turn increases the likelihood of rupturing the anterior cruciate ligament. A study conducted by Wojtys et al found that when women are on oral contraception, the rates of ACL injuries during the ovulatory phase are reduced – which links back to the rise in LH and FSH levels.

However, it is important to note that this research hasn’t been carried out on a wide scale yet – so all of these findings are based on small sample groups and cannot be judged to provide an accurate correlation. Due to the smaller sample size, ‘trends’ appear more easily when in reality it could be completely coincidental.

Fixture Congestion

Another important factor is fixture congestion within the women’s game. This may seem counterintuitive given the fact that the Women’s Super League currently only features twelve teams while the Premier League boasts twenty – but the WSL season starts much later. The Premier League campaign usually kicks off in early August, with thirty-eight games to be played before the end of May.

However, the FA have just announced that the 2023/24 Women’s Super League season will not start until the final weekend of September. Teams must play 22 games in this time, alongside two domestic cup competitions – and some clubs will also be involved in European football too.

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While I’m not trying to suggest that the men will have played 22 games by the end of September, the women’s schedule could quite easily be stretched out by another six weeks or so to allow greater rest period between games. Potentially, the calendar could be designed in co-operation with UEFA to ensure that league games are not played in the same week as Women’s Champions League fixtures to offer increased recovery periods for female footballers.

Women’s football also has international tournaments interspersed throughout the year. In the men’s game, these tend to solely be international qualifiers or the occasional friendly here and there – though the women are subjected to one-off mini tournaments such as the Arnold Clark Cup. In this year’s instalment, England played three games in six days! When there’s nothing on the line other than a meaningless trophy, it seems utterly bizarre to add more games into an already congested season.

Playing Surface

Arsenal boss Jonas Eidevall appeared to blame the playing surface at Leigh Sports Village for Leah Williamson’s injury. In a post-match interview, he pointed out that with ‘pitches like that, players are going to get injured.’

Women’s football teams often share facilities with other clubs – Manchester United’s ground is also used by the team’s academy and a professional rugby league side. In comparison to the men’s game, the playing surface is used far more frequently. At first glance, it looks as if Eidevall may be onto something.

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However, Leah Williamson is currently one of three Arsenal players out with an ACL injury – joining Vivianne Miedema and Beth Mead in the recovery room. Miedema tore her anterior cruciate ligament in a Women’s Champions League group stage game against Lyon – but that game was played at the Emirates Stadium, so the pitch quality can’t be at fault. Beth Mead’s injury also came at the Emirates Stadium, as she was forced off during the club’s loss to Manchester United in North London.

When two of Arsenal’s three ACL injuries have come at world-class sporting facilities, and the club’s home ground nonetheless, it feels as if Jonas Eidevall is simply looking to pin the blame on someone else. Playing surfaces do need to improve in the women’s game, but it’s not fair to blame the pitch at Leigh Sports Village in this particular case.

Football Boots

With women’s football only really bursting to the forefront in recent years, there’s been a noticeable lack of football boots designed with female athletes in mind. Instead, elite players are forced to wear boots designed for men – who have different needs for support and structure.

This ties back to my earlier point about hip structure, as this causes a difference in the way women run. As the angle between their hip joint and knee is increased comparative to men, women find themselves struggling with the stud placement on male boots. They are specially designed to allow maximum traction based on the average angles required by a male athlete – but due to the anatomical differences between the two sexes, women often end up fighting the ground as their studs become stuck. When this happens, an overextension of the knee is likely – and that’s how you end up with an ACL tear.

Lack of Investment

There’s also an undeniable lack of investment in the women’s game. From a young age, boys are offered all kinds of support and an intense training schedule if they wish to make it big in the professional game. Girls haven’t been awarded the same luxury, and while things are beginning to change now, it’ll be some time before we see the effects of that.

The lack of investment also carries over to rehabilitation. It’s estimated that just 6% of sports science studies are carried out solely on women, meaning there’s far less data to assess the best options for recovery – or even prevention – of an anterior cruciate ligament injury.

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That’s emphasised by Aoife Mannion, who has torn the ACL in her right knee twice. The defender’s first injury came while she was playing for Manchester City in November 2019, and after moving across the city to Manchester, she suffered the same injury in February 2022. When playing for two of the biggest – and richest – clubs in the sport, there’s absolutely no excuse. There would be uproar if the same had happened to Ronaldo or Messi, for example – but because it’s a woman, it seems to be perfectly acceptable and brushed off.

Furthermore, more investment from club owners would allow for bigger squads. With a greater transfer budget, clubs would be able to sign more, higher quality players – once again reducing the workload for the whole team. That would allow increased squad rotation, which currently doesn’t happen due to the drop-off in quality between the preferred starting eleven and the bench.


It’s clear that more investment is needed – from an early age, at a professional level, and everywhere in between. Fixtures could be spread out over a longer time period to allow for more rest and recovery between games, and pointless international friendlies should be scrapped to ease the pressure on these professional athletes. At the same time, more studies need to be conducted on the female body so that clubs can finally understand the true impact that hip structure and hormonal changes have on the anterior cruciate ligament.