ACL tears are usually caused by a sudden pivoting action. A common sporting occurrence, they can range in severity and often require surgery to restore full mobility.

ACL Tears

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What is an ACL Tear?

An ACL tear is an injury to the anterior cruciate ligament. The ACL is one of four important ligaments in the knee. It helps connect your thighbone (femur) to your shinbone (tibia) and provides rotational stability. ACL tears usually occur in sports that involve sudden stops or starts with pivoting manoeuvres, and patients often notice a popping sound when the injury occurs. This is followed by severe pain, swelling, restricted movement and a general feeling of the knee giving way. 

ACL injuries are graded depending on the severity of the sprain ranging from a mildly damaged ligament (grade one) to a complete tear where the ACL has been split in two (grade three). Some people are genetically predisposed to this injury, and if it happens on one side they are at a greater risk of it happening to the other.

How is it treated? 

Very minor sprains may heal without surgery and in some cases can be treated with physiotherapy exercises and rest. If the ACL is completely torn, it will not heal without surgery and it cannot be stitched back together. Reconstructive surgery can be performed arthroscopically, and the damaged ACL is replaced with new tissue. To achieve this, tendons are usually taken from your hamstrings, patella tendon or quadriceps tendon and grafted into tunnels within the bones.

How long will it last?

The operation takes between 1-2 hours and will usually require an overnight stay. You will be able to move your knee directly after surgery and rehabilitation exercises can begin almost immediately. Following a rehabilitation program is essential to restoring mobility and motion as well as achieving the best long-term outcome. Full healing can take up to a year, with a return to rigorous sports and activities possible after 9-12 months.

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