The anterior cruciate ligament (ACL) is the ligament inside the knee that provides stability during pivoting, twisting, and cutting movements. Injuries to this ligament is becoming more common due to a number of factors and the increased participation in sport. An ACL rupture may occur in the mid-substance or at either end (its attachment to the femur and tibia).
The ACL connects the femur (thigh bone) to the tibia (shin bone) and acts to stabilise the knee by preventing the tibia from moving too far forward in relation to the femur and preventing excessive rotation between the two bones. ACL rupture is caused by the body pivoting or rotating around a planted foot. This movement is common in sports such as AFL, Netball, Soccer and Rugby but can occur during any activity that involves this pivoting motion.
At the time of injury patients will describe a 'pop' within the knee or a feeling that the knee gives way. This is followed by acute pain and in most cases an inability to play out the game or continue the activity you were doing. After the initial injury the knee will swell, walking may become difficult and you may require the use of crutches. This tends to settle down in 10-14 days. Some patients are unaware of the severity of their injury at the time and only notice symptoms when they attempt to return to sport or previous activities. These symptoms include:
A thorough history and examination is usually sufficient to be suspicious of an ACL injury. Patients will often describe a dis-trust in their knee or a feeling of instability. On Examination there will be excessive forward movement of the tibia in relation to the femur compared to the other knee.
MRI is the gold standard investigation and will be requested by your doctor or surgeon. MRI will be able to confirm the diagnosis of ACL rupture but also allow us to assess the other structure within and around the knee that may have also been damaged.
There is a wide range of treatment options for your ACL injury and the decision will come down to extent of the injury, associated damage to the knee, anticipated outcomes and goals. In a select group of patients managing ACL ruptures non-surgically may be an option but should be discussed with your surgeon.
As the ACL does not heal on its own a surgical reconstruction is recommended if you wish to return to your previous activities or level of sport. This involves taking tissue from your knee and passing it in the line of the previous ACL to stabilise the knee.
There are a number of graft options each with their pros and cons, which Dr Shales will discuss with you.
The long-term outcome for ACL reconstruction is good. Over 80% of patients return to sport with over 60% returning to their previous level. When returning from an ACL injury there is a return to sport guideline which helps inform you when you are physically ready to return to sport.
ACL injuries are the most feared injury to a sports person or anyone who lives an active lifestyle. Fortunately there is a well researched and structured exercise program that has been shown to reduce ACL injury rates by up to 67%.
Please see the links below for more information and further reading regarding ACL injury prevention.
In conclusion, ACL injuries represent a significant challenge to patients who live active lifestyles and participate in sports at any level. Advancements in surgical techniques, rehabilitation protocols, and preventive strategies have improved outcomes for individuals with ACL injuries, facilitating a return to an active lifestyle and sports participation. With a comprehensive approach that encompasses both surgical intervention and rehabilitation, Orthopaedic surgeons play a crucial role in managing ACL injuries and helping patients regain strength, function, and confidence in their knees.
