How do I know if I've torn my ACL?

An ACL tear is a common injury, particularly for those who play competitive and demanding sports. No matter whether you are a weekend or a professional athlete, the adrenaline of the game and your personal pain tolerance can make it difficult for you to know the severity of an injury.

However, determining whether you have an ACL tear can actually be quite easy – if you know what to look for.

The following are telltale signs that you have torn your ACL:

You heard a ‘pop.'

People who have experienced an ACL tear often report a popping sound at the time of injury. Most people are surprised by how loud this can be, with team players and bystanders often able to hear the sound as well. The ACL is a very taught ligament and when it experiences a strain that causes it to tear, the result is similar to a rubber band snapping.

You experience an intense and sudden onset of pain in the knee.

If you don’t hear the pop, you might feel the joint move and a sudden onset of pain in your knee. The level of pain experienced is dependent on the severity of your injury. Sometimes it feels like you have dislocated your knee.

Your knee has become unstable.

The ACL is critical to the stability of your knee joint. When you tear your ACL, you may find it difficult to place any weight on the injured knee without it feeling unstable or collapsing.

Your knee has swollen quickly.

A tear to your ACL causes the knee to swell rapidly, often within minutes of the injury. There is a blood vessel in your ACL that, when it is torn, causes the knee joint to fill with blood and swell. Most patients report that their knee swelled after injury.

While these symptoms can aid you in deciding whether your knee injury could be more severe than you thought, it is important to see a doctor so that he/she can perform a proper diagnosis on your knee. Your doctor will perform a range of tests to look for signs of instability in your knee and may recommend you undergo an MRI to determine whether the ligament is completely or partially torn, and to check for signs of any associated injuries to your knee.

To help you to better understand the treatment and rehabilitation of an ACL tear, top Orthopaedic Surgeon in Newcastle and the Hunter Valley, Dr Stuart MacKenzie has created a free guide on knee reconstructions.