Anterior Cruciate Ligament (ACL) injuries have plagued women’s football in recent times. Football-focused studies suggest women are six times more likely to tear their ACL than men, and consequently, within the last 18 months, 195 elite female players were estimated to have suffered the injury.
In the last 12 months, many teams have been left with depleted squads due to the injury crisis. At present, 13 WSL players are going through recovery from an ACL injury, including Man United defender Gabby George and Leicester winger Hannah Cain. One of the worst affected teams has been Arsenal, who have seen key players Beth Mead, Vivianne Miedema, Leah Williamson and Laura Wienroither side-lined due to the injury in recent months.
Chelsea are another WSL club who have been affected in recent weeks, with two of their players picking up ACL injuries within the last month. Star striker Sam Kerr had her season cruelly cut short in January due to an ACL injury, while Mia Fishel sustained the same injury on international duty with the USA last week. Unfortunately, ACL injuries are occurring left right and centre in the women’s game at the moment, which is having a devastating impact for both the players and clubs concerned.
Staggeringly, there were over 25 players (enough for an entire squad) that missed out on playing in the Women’s World Cup last summer due to ACL tears, which puts into perspective just how serious of an issue this ‘epidemic’ has become.
What is an ACL injury?
The ACL is a tough band of tissue which joins the thigh bone to the shin bone at the knee joint. It runs diagonally through the inside of the knee and gives the knee joint stability, while also helping to control the back-and-forth movement of the lower leg.
The ACL can be torn if your lower leg extends forward too much, or if your knee and lower leg are twisted. Common causes of an ACL injury include changing direction or stopping suddenly, landing incorrectly from a jump, or having a collision, such as during a tackle.
ACL injuries are common in sport, with football having the most ACL incidents. The injuries are usually non-contact, with players often seen falling to the ground in pain following an awkward landing or sudden change of direction. ACL injuries are undoubtedly one of the most devastating injuries in football.
Where complete ruptures occur, reconstructive surgery is usually required. This involves the torn ligament being replaced with a tissue graft to mimic the natural ACL. According to research, the average recovery time for an ACL tear is around eight months, however, this can differ depending on the severity of the injury.
Why Are Female Players at Greater Risk?
Although more research into ACL injuries and how to prevent female players from suffering them needs to be done, some studies have identified some of the risk factors that could play a role in the increased risk of injury for women. There are a wide range of factors that could contribute including anatomy, biomechanics, hormones, workload and gender disparities.
Anatomy
Anatomy is one of the main contributing factors that puts women at greater risk of ACL injuries than men. The female pelvis is wider than a man’s, which changes the mechanics of how the thigh bone, tibia and femur function. This puts more stress on soft tissues that support your joints. Also, women are typically more knocked-kneed, meaning their knees usually tilt inward. This alignment alters the knee joint, which increases the risk of injury during movements such as pivoting, jumping, and landing. Another factor is the ACL tissue is usually thinner in women. As a result, it takes less force for the ACL to tear than it would for men.
Biomechanics
The biomechanics of men and women differ, which could also be a factor. After jumping, women tend to land in an upright posture, which results in less core engagement and straighter knees. On the other hand, men usually land with more core engagement and bent knees, which in turn brings a lower risk of ACL injury.
Hormones
Studies have shown that the elasticity of collagen in the knee is impacted throughout different stages in the menstrual cycle, resulting in a higher risk of ACL injury. Additionally, women have a lot more oestrogen. This hormone, which is essential to bone growth, fluctuates during a woman’s menstrual cycle, which may have an impact. Oestrogen can also cause looseness in ligaments and tendons, which can make women more prone to injury.
Workload and Gender Disparities
ACL injuries among female players have also been linked to high workload. With the rapid growth in popularity of the women’s game, the frequency of fixtures has increased, and the physical demands on players have also increased. Despite this, female-specific sports science and access to strength and conditioning specialists is still lagging behind in the women’s game. In childhood, girls have usually not been exposed to the same elite level of training as early as boys and have not built up the same capacity or base level of strength and endurance, which increases vulnerability and puts them at greater risk of injury.
Chelsea Women’s player Fran Kirby commented on this, saying: "It's important to get the basic fundamentals really young - there is a difference when it comes to how we (boys and girls) are brought up playing.
“The boys are doing gym work and learning basic running mechanics at the age of six. When I was coaching at Reading the grassroots girls couldn't even access a gym. The most important thing is teaching young girls the basic mechanics of being a footballer and being a sportsperson."
Improving access to female-specific sports science and strength and conditioning could be key to reducing the number of ACL injuries among women in the future.
Football Boots
Another potential factor is women are playing in boots designed for men. According to a recent report coordinated by the European Club Association, as many as 82 per cent of female players surveyed experience high levels of discomfort wearing football boots. Women’s feet, heels and arches are shaped differently to men’s. Women also move and run in a different way to men, however the length of studs on boots are designed around male movement and traction. This increases the risk of women getting their boot stuck in the surface and an injury being caused.
It is also worth noting that women’s teams are often likely to be playing on uneven surfaces where the men’s teams have played the day before, which could also increase the risk of injury.
What is Being Done to Prevent ACL Injuries in Women’s Football?
In December 2023, European football’s governing body UEFA announced the introduction of an expert panel on women’s health to seek a deeper understanding of ACL injuries and their frequency among female players. This is a step in the right direction in terms of reducing the risk of ACL injuries among women and will help to understand why injuries are occurring so frequently, but also how we can reduce the frequency of ACL injuries.
The central focus of this panel is to gain a deeper understanding of ACL injuries among female players. It has been reported that the long-term aim is to publish a UEFA consensus on ACL injury prevention and management by the summer of 2024, plus an up-to-date ACL injury prevention programme.
In terms of injury prevention, FIFA has already developed training programmes (such as the 11+) that are designed to prevent ACL injuries and have been implemented by clubs and national teams. However, there is still a need for female-specific programmes to be developed, as ACL injuries are becoming a more regular occurrence in the elite women's game.
In terms of football boots, some brands have begun to invest in manufacturing female-specific boots. Puma were the first to launch a women’s specific fit in July 2021, and Nike followed suit with the launch of the Phantom Luna boots ahead of the World Cup last year. Nike said the boot is made up of “three key elements: traction, fit and feel – all of which were designed with female-specific feedback, needs and anatomy in mind”.
The introduction of female-specific boots is also a positive step; however, it is worth noting the Phantom Luna is offered to both male and female players - it is not exclusively a women’s boot. More work must be done to ensure women have access to kit that is designed solely for them. The European Club Association has announced a study commissioned to highlight the benefits of well-designed footwear, which should have a positive impact.
In conclusion, ACL injuries are a huge issue in women’s football, and more research must be completed to prevent these devastating injuries from occurring so regularly in the women’s game.