From the Research
Expected exam findings for a right knee medial collateral ligament (MCL) tear include pain and tenderness along the medial aspect of the knee, particularly over the MCL itself, as well as pain with valgus stress testing, which is supported by the most recent study 1. The patient will likely demonstrate pain with valgus stress testing, where the examiner applies a force to the lateral knee while stabilizing the thigh, pushing the knee inward. Depending on the severity of the tear, there may be varying degrees of joint laxity with this test. For grade I tears, there is pain but minimal laxity; grade II tears show partial laxity with a firm endpoint; and grade III tears demonstrate significant laxity with no firm endpoint. Patients often report pain with weight-bearing, particularly when pivoting or changing direction. Swelling may be present but is typically less pronounced than with other knee injuries like ACL tears. The patient might also demonstrate an antalgic gait, favoring the affected leg. Range of motion testing may reveal pain at the extremes of motion, especially with external rotation of the tibia. These findings reflect the MCL's role in providing medial stability to the knee joint, resisting valgus forces that would otherwise push the knee inward excessively, as described in 2, 3, 4, 5.
Some key points to consider when examining a patient with a suspected MCL tear include:
- Pain and tenderness along the medial aspect of the knee
- Pain with valgus stress testing
- Varying degrees of joint laxity depending on the severity of the tear
- Pain with weight-bearing, particularly when pivoting or changing direction
- Swelling, although typically less pronounced than with other knee injuries
- Antalgic gait, favoring the affected leg
- Pain at the extremes of motion, especially with external rotation of the tibia, as noted in 1.
It is essential to note that the diagnosis of an MCL tear is often made based on a combination of history, physical examination, and imaging studies, such as MRI, which is considered the gold standard for diagnosis, as mentioned in 2.