In the McMurray test, which combination of tibial rotation and knee motion tests the medial meniscus?

• A. External rotation with valgus stress during extension to flexion
• B. Internal rotation with varus stress during flexion
• C. External rotation with varus stress during flexion
• D. Internal rotation with valgus stress during extension

Answer: (A)

The key idea is that the McMurray test isolates a torn medial meniscus by stressing the tissue with a specific combination of tibial rotation, knee motion, and collateral stress. For the medial meniscus, externally rotating the tibia and applying valgus stress while moving the knee from extension into flexion compresses the medial meniscal tissue between the femoral condyle and tibial plateau. If a tear is present, this maneuver often reproduces a click or pain as the torn fragment catches in the joint.

Patterns that involve internal rotation with varus stress, or external rotation with varus stress, tend to stress the lateral side rather than the medial meniscus, so they’re not the classic maneuver for a medial tear. Likewise, combining valgus stress with internal rotation during extension doesn’t isolate the medial meniscus as effectively as the extension-to-flexion sequence with external rotation and valgus stress.

So, externally rotating the tibia with valgus stress while moving from extension to flexion best indicates a medial meniscal issue.