Anterior Cruciate Ligament (ACL) Tear
SUMMARY
Causes- Violent over-twisting of the knee
- Lower leg forced forward
- Common in skiing
- Sudden change of direction
- Audible pop sound at time of the injury
- Minor tears - slight pain at start, increasing
- Swelling and stiffness
- Unnatural movement of knee joint
- Major tears - leg will not hold weight
- Combination of rest and physiotherapy
- Knee brace to correct alignment and promote healing
- RICE within first 72 hours
- Strengthning exercises in later recovery
- Surgery may be required for major tears or ruptures
What is an ACL Tear?
An ACL Tear is a common sporting injury affecting the Anterior Cruciate Ligament of the knee. The ACL Ligament joins the back of the thigh bone (femur) to the front of the shin bone (tibia) giving the knee joint its stability. It prevents over extending the knee (hyperextension) and it stops the knee twisting too far. There are levels of severity of an ACL Tear, from a slight tear in the ligament to a complete rupture. A complete rupture of the ACL will result in significant pain and very little function of the knee joint. Surgery is potentially the only way of treating a complete rupture. The levels of tear are as follows:- Grade 1 tear: a small number of fibres are torn resulting in some pain but the joint will function relatively normally.
- Grade 2 tear: a large number of fibres are torn and the knee joint will lose a lot of functionality.
- Grade 3 tear: the ACL ligament is completely torn and the knee becomes unstable. There will be very little if no function of the knee. Surgery is most likely required.