Which test is commonly used to evaluate the anterior cruciate ligament?

• A. Trendelenburg test
• B. McMurray's test
• C. Lachman test
• D. Squeeze test

Answer: (C)

The Lachman test is a widely used clinical examination technique specifically designed to assess the integrity of the anterior cruciate ligament (ACL) in the knee. This test involves flexing the knee to about 20-30 degrees and applying anterior pressure to the tibia while stabilizing the femur. A positive Lachman test is indicated by excessive forward movement of the tibia relative to the femur, suggesting a possible tear or injury to the ACL.

Its effectiveness is due to the specific position of the knee, which maximizes tension on the ligament, allowing the examiner to detect even partial tears. This makes it a reliable indicator for ACL pathology, particularly when compared to other tests, which may be less sensitive or specific for evaluating this ligament.

In contrast, the Trendelenburg test evaluates hip stability and gluteal muscle function, the McMurray's test is used to identify meniscus tears, and the Squeeze test assesses for ankle fractures or syndesmosis injury, none of which directly evaluate the ACL.