Which test differentiates a meniscal tear from a ligamentous knee injury?

Which test differentiates a meniscal tear from a ligamentous knee injury?

• A. Lachman test
• B. Apley grind
• C. Thessaly test
• D. McMurray test

Answer: (D)

The key idea is using a knee test that specifically probes meniscal tissue while minimizing reliance on ligament stability. The maneuver known as the McMurray test provokes the menisci by combining knee flexion, rotation of the tibia, and then extension. If a torn meniscus is present, this sequence often produces a painful click or a clear joint-line pain as the torn fragment is pinched between the femur and tibia. This mechanical sign is characteristic of a meniscal tear and helps distinguish it from a ligamentous knee injury, which would more likely show laxity or abnormal translation on ligament-specific tests. In contrast, tests like the Lachman primarily assess anterior cruciate ligament integrity. A positive Lachman points toward a ligament tear rather than a meniscal problem. Tests such as Apley grind or Thessaly can indicate meniscal pathology as well, but the McMurray maneuver is the classic, most specific test that points toward a meniscal tear when the clinician observes the joint-line pain or a click during the maneuver.

The key idea is using a knee test that specifically probes meniscal tissue while minimizing reliance on ligament stability. The maneuver known as the McMurray test provokes the menisci by combining knee flexion, rotation of the tibia, and then extension. If a torn meniscus is present, this sequence often produces a painful click or a clear joint-line pain as the torn fragment is pinched between the femur and tibia. This mechanical sign is characteristic of a meniscal tear and helps distinguish it from a ligamentous knee injury, which would more likely show laxity or abnormal translation on ligament-specific tests.

In contrast, tests like the Lachman primarily assess anterior cruciate ligament integrity. A positive Lachman points toward a ligament tear rather than a meniscal problem. Tests such as Apley grind or Thessaly can indicate meniscal pathology as well, but the McMurray maneuver is the classic, most specific test that points toward a meniscal tear when the clinician observes the joint-line pain or a click during the maneuver.