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How is the anterior cruciate ligaments (ACL) injured?
The anterior cruciate ligament (ACL) is the most common ligament to be injured. The ACL is often stretched and/or torn during a sudden twisting motion (when the feet stay planted one way, but the knees turn the other way). Skiing, basketball, and football are sports that have a higher risk of ACL injuries.
The posterior cruciate ligament (PCL) is also a common ligament to become injured in the knee. However, the PCL injury usually occurs with sudden, direct impact, such as in a car accident or during a football tackle.
How are collateral ligaments injured?
The medial collateral ligament is injured more often than the lateral collateral ligament. Stretch and tear injuries to the collateral ligaments are usually caused by a blow to the outer side of the knee, such as when playing hockey or football.