Ligament · Knee

Anterior cruciate ligament

Ligamentum cruciatum anterius

One of the two ligaments that cross inside the knee. It runs upward and backward from the front of the shin plateau to the inside wall of the outer femoral condyle, and its job is to stop the shin sliding forward on the thigh bone and to limit rotation. It is best known for how it fails: most ACL injuries happen without contact at all, when someone decelerates, lands or pivots with the knee collapsing inward. That is why ACL care is as much about retraining landing and single-leg control as it is about the ligament itself.