Which special test is used to assess the medial collateral ligament (MCL)?

The valgus stress test is utilized to assess the integrity of the medial collateral ligament (MCL) specifically. This test evaluates the MCL by applying a lateral force to the knee while stabilizing the ankle, which creates a valgus (outward) stress that targets the ligament. If the MCL is intact, the joint should maintain its stability when the test is performed. However, if there is a sprain or tear, increased laxity or pain will typically be observed in the medial aspect of the knee during the test, indicating potential injury to the MCL.

In contrast, the varus stress test primarily assesses the lateral collateral ligament (LCL) by applying medial force to the knee. The anterior drawer test and Lachman's test are designed to evaluate the integrity of the anterior cruciate ligament (ACL) instead. Thus, the valgus stress test is the most appropriate choice for determining the condition of the MCL.