Posterior cruciate ligament (PCL) injuries to the knee occur less often than injuries to the anterior cruciate ligament (ACL), and they frequently are not recognized. The ACL is the more familiar of the two structures, but both ligaments contribute to the knee’s stability. Therefore, if either of these ligaments is torn or injured, the person may experience unpleasant symptoms. Specifically, swelling, pain, a feeling of loss of stability in the knee joint is likely to occur.
Ligaments are strong, fibrous bands of connective tissue that hold bones together. For example, the anterior and posterior cruciate ligaments attach the femur or thighbone to the tibia or shinbone. These two ligaments create a cross to form an “X” in the middle of the front of the knee.
Many experts describe the posterior cruciate ligament as the primary stabilizer of the knee. It is stronger and broader than the ACL. Most of the time, posterior cruciate ligament injuries happen when the knee is bent and force is applied to the front of the shin. These injuries can also occur due to hyperextension or in association with stress or rotational force.
Posterior cruciate ligament injuries may have been over-simplified in the past. However, a tear of the ligament can result in no future disability to severe impairment. Therefore, treatment of PLC injuries depends on several factors, including the severity of the injury.
Posterior cruciate ligament injury causes
When the tibia or shinbone is forcefully struck just below the knee, it can cause posterior cruciate ligament injuries or tears. They can also happen if a fall occurs onto a flexed or bent knee. Among the situations in which these injuries can happen are:
- Sports activities: Soccer and football players are at risk for posterior cruciate ligament injuries if their knee is bent with the foot pointing toward the ground when they fall. It is because the shinbone strikes the ground first and forces it back, tearing the PCL. If the player is tackled when the knee is bent, this injury may also occur.
- Motor vehicle accidents: If a person’s bent knee strikes the dash in a motor vehicle accident, the shinbone may be forced backward, causing the PCL to tear.
- Running injuries: Certain types of running injuries may also result in posterior cruciate ligament injuries.
Posterior cruciate ligament injury risk factors
The main risk factors for injuring the posterior cruciate ligament are being male and participating in contact sports such as soccer and football.
Other situations, behaviors, and conditions that may increase the likelihood of PCL injuries include:
- Sustaining an injury during sports activities
- Being involved in a motor vehicle accident
- Falling on a flexed (bent) knee
- Being struck forcefully on the shin directly below the knee
- Having a dislocated knee.