The anterior cruciate ligament (ACL) is taut in which position of the knee and resists which specific movement?

• A Full flexion; resists posterior translation of tibia on femur
• B Mid-range flexion only; resists valgus stress
• C Full extension; resists anterior translation of tibia on femur ✓
• D Full extension; resists posterior translation of tibia on femur

Explanation

The ACL runs from the anterior intercondylar area of the tibia to the posterior part of the medial surface of the lateral femoral condyle. It is taut in full extension and resists anterior translation of the tibia on the femur (positive anterior drawer test) and also limits hyperextension and internal rotation. The posterior cruciate ligament (PCL) resists posterior tibial translation. Neither cruciate directly resists valgus or varus stress — these are roles of the collateral ligaments.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.