Medial Collateral Ligament (MCL) and Posterior Cruciate Ligament (PCL) are two of the four ligaments providing stability to the knee and preventing the knee from moving too far in a specific direction. The other two ligaments are MCL and PCL. There is also the ACL and LCL. In addition to stability, these ligaments have the crucial function of keeping the knee from extending too far.
The MCL is located on the inside of the knee. This ligament helps keep the knee from bending inward (valgus). The PCL is also located on the inside of the knee, just behind the ACL. The primary function of the PCL is to prevent the tibia from moving backward with relation to the thigh bone.
The most common causes of injury to the MCL or PCL are sports, exercise, or trauma. Trauma may include motions like a forceful twist of the knee to one side or a direct blow to the knee. Both the MCL and PCL can incur injury in conjunction with an ACL injury.
Moving too far in a specific direction. (The other two ligaments are MCL and PCL, there is also the ACL and LCL.) In addition to stability, these ligaments have the crucial function of keeping the knee from extending too far. The MCL is located on the inside of the knee. This ligament helps keep the knee from bending inward (valgus). The PCL is also located on the inside of the knee, just behind the ACL. The primary function of the PCL is to prevent the tibia from moving backward with relation to the thigh bone.
Signs and Symptoms
- Pain in the knee, especially at the inside of the knee
- Knee swelling
- Bruising
- Popping sound
- Instability in the knee or a feeling of knee "giving out"
- Locking or catching in the knee joint or difficulty walking