Posterior cruciate ligament (PCL) injury

Definition

A posterior cruciate ligament injury is a partial or complete tearing or stretching of any part of the posterior cruciate ligament (PCL).

Alternative Names

Considerations

Your doctor will perform a physical examination to check for signs of PCL injury. This includes moving the knee joint in various ways (these manipulations are called a posterior drawer test and a quadriceps active drawer test).

Your doctor may also check for the presence of fluid in the knee joint (the ballottement test). This test may show joint bleeding (hemarthrosis).

PCL injury may be seen using the following tests:

• Knee MRI
• Knee joint x-ray

Causes

The posterior cruciate ligament (PCL) is a powerful ligament extending from the top-rear surface of the tibia to the bottom-front surface of the femur. The ligament prevents the knee joint from posterior instability -- that is, instability in the back of the joint.

The PCL is usually injured by hyperextension (overextending the knee), which can happen if you land awkwardly after jumping. The PCL can also become injured from a direct blow to the flexed knee, such as smashing your knee in a car accident (called "dashboard knee").