Cruciate ligament is found in the knee joint.

Cruciate ligaments (also cruciform ligaments) are pairs of ligaments arranged like a letter X. They occur in several joints of the body, such as the knee joint and the atlanto-axial joint. In a fashion similar to the cords in a toy Jacob's ladder, the crossed ligaments stabilize the joint while allowing a very large range of motion.

The cruciate ligaments of the knee are the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). These ligaments are two strong, rounded bands that extend from the head of the tibia to the intercondyloid notch of the femur.

The ACL is lateral while the PCL is medial. They cross each other like the limbs of an X. They are named for their insertion into the tibia: the ACL attaches to the anterior aspect of the intercondylar area, the PCL to the posterior aspect. The ACL and PCL remain distinct throughout and each has its own partial synovial sheath. Relative to the femur, the ACL keeps the tibia from slipping forward while the PCL keeps the tibia from slipping backward.

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