The ACL
Anterior cruciate ligament · ligamentum cruciatum anterius
A strong band inside your knee that stops the shin sliding forward and the knee twisting.
What it does
The ACL runs diagonally inside the knee from the back of the femur to the front of the tibia. It stops the shin sliding forward under the thigh and limits twisting, keeping the knee stable when you change direction, land or pivot.
Surprising fact
Most ACL tears happen without any contact, during a sudden landing or change of direction, and female athletes tear it several times more often than male athletes in the same sports.
Why it matters
An ACL tear often comes with a pop and rapid swelling. Training programmes that teach good landing and cutting technique cut the risk substantially.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.