Anterior cruciate ligament (ACL) injuries are prevalent in sports that involve jumping/landing and high speed change of direction, for example AFL, netball, basketball and skiing. The role of the ACL is to provide stability to the knee joint both in a rotational and anteroposterior direction. The ACL will “fail” (i.e. a partial or full tear) if the forces at the knee joint are stronger than what the ligament can withstand.
We know that ACL ruptures occur in approximately 3% of recreational athletes and 15% of professional athletes. Female athletes, however, are 2-10 times more likely to sustain an ACL injury than their male counterparts.
Why are females at a higher risk of ACL rupture?
There are several risk factors that increase a female’s risk of injury to the ACL:
Females having a wider pelvis than males, therefore there is a greater angle between the hip and the knee, known as the Q-angle. The Q-angle refers to the effect of the quadriceps muscle on the knee. In increased Q angle, as seen in females, increases the lateral pull of the quads which is thought to place the ACL at greater risk of injury
Because females have an anatomically wider pelvis, the knees sit more medial compared to the hips. This predisposes the knee into a position of valgus, where the knee collapses inwards on activities such as landing and changing direction. This position increases load through the ACL, therefore increasing the risk of damage
Females are more likely to have looser ligaments, therefore meaning the ligament is more easily damaged
Females generally have less powerful muscles than males. Due to the increased flexibility of ligaments, muscle strength is even more important to support the joint. Muscle strength and power needs to be adequate to be able to withstand the demands of sport and protect the knee during high-risk movements (e.g. landing, high-speed change of direction)
Higher oestrogen levels can make ligaments more lax, therefore predisposing them to injury. Females have a higher risk of ACL rupture at certain points during the menstrual cycle due to the hormonal changes that occur
What can we do about this increased risk of ACL rupture? How can ACL tears be prevented?
While some of the risk factors outlined above cannot be modified, such as anatomy and hormones, there is still a lot that can be done to prevent ACL injuries. The main focuses of an ACL injury prevention program are the biomechanical and strength risk factors.
Strength is addressed by developing a strength-based exercise program, ideally performed in a gym, targeting muscles that assist in both stabilising the knee joint and improving control during high risk activities. Key muscle groups to address are the quadriceps, hamstrings, calf, gluteals and core. A combination of pure strength/power exercises and more functional exercises should be used.
Biomechanics are addressed by assessing how a person moves and identifying and correcting any parts of the movement that predispose to ACL injury. For example, landing with the knee collapsing inwards is high risk, therefore correcting this by coaching the person to land with the knee in a better position helps reduce the risk. The same can be said for changing direction.
This should initially be done in a controlled environment, eventually progressed to simulate the demands of sport, for example with contact or an opponent. While it does take time to change biomechanics and movement patterns, this is potentially the most important component of preventing ACL injuries.
What if I have already ruptured my ACL?
The principles of rehabilitation post ACL reconstruction are very similar to the principles of prevention. The initial post-operative phase involves reduction of pain and swelling, range of movement and muscle activation. Subsequent phases involve muscle strengthening, correction of movement patterns and simulation of sports-specific requirements.
Should I see a physiotherapist prior to a surgeon for ACL tears?
Its not too important who you see first, though getting early physiotherapy intervention to assist with swelling management, range of motion and power will assist. Our expert ACL physiotherapists can put you in contact with excellent surgeons, so everyone works as a team to give you, the patient, the best possible outcome following an ACL rupture. The main priority is that you get in be seen by a highly skilled physiotherapist or doctor, to get an accurate diagnosis and start to create the best management plan for yourself.
Should you or your club need any advice about ACL injury prevention in females or assistance with rehabilitation post ACL reconstruction, please contact us, as we have had hundreds of ACL injuries come through our clinic over the years, with very successful outcomes.
We also provide a range of other treatments no matter your age of fitness level. If you have any questions, feel free to get in touch with our friendly team. You can book your next sports physiotherapy appointment with us by calling 1300 369 930 or you can book online.