Anterior Cruciate Ligament (ACL) Injury

The ACL is a ligament that lies within the knee joint itself and its role is to prevent the forward movement of the shin bone in relation to the thigh bone.

An ACL injury typically occurs either during a ‘cutting’ motion or a single leg landing. A typical ACL injury occurs when the knee is externally rotated with 10-30 degrees of knee flexion when the foot is planted on the floor. As the person decides to change direction the knee falls inwards (creating what is known as a knee valgus position) and the torso twists. With the ACL taught in knee flexion, this extra demand on the ligament due to altered ground reaction forces can lead it to fail or rupture completely.

When discussion the mechanism of injury, people would usually report an audible click / pop or as if something had come out and gone back in again, acute pain at point of injury with swelling often quick to appear within the joint and reports of the knee feeling unstable

On examination the person typically presents with:

• Restricted movement

• Widespread mild tenderness

• Lateral or medial joint line tenderness.

There are a number of special tests that help diagnose an ACL injury which include the anterior draw test, lachmann test and pivot shift test. The Lachmann test is the most accurate examination technique and is commonly used.

How can physiotherapy help?

There is LOTS of evidence being released about the best way to rehabilitate a person following an ACL injury. If a person wanted to return to high level sport that involved lots of dynamic movements / changing direction then surgery would have usually been the option. However, there is more evidence to suggest that actually with the correct rehabilitation programme you may not need to undergo surgery, as evidence as shown similar outcomes between people undergoing surgery and those who have none-surgical interventions

However, if you were to undergo surgery there has been a large focus on return to play protocol. Literature suggests that 9 months post-surgery, following a detailed rehabilitation programme, is the time when people should look to return to sport. Other papers say 12 month is more ideal. What needs to be remembered is that people recover quickly, and have different demands to meet with their activity and a barrage of tests looking at strength, dynamic movement and control etc will accurately reflect an athletes true capacity to return to sport.

Following surgery physiotherapy can help by:

• Providing you education and advice

• Working with you to create a programme and the milestones required to progress rehab.

• Cryotherapy

• Range of movement exercises

• A graded exercises programme

• Manual therapy

• Motor control and proprioceptive exercises

• Return to sport assessment, discussion and advice