Which set of tests assesses the collateral ligaments of the knee?

• A. Lachman and Anterior Drawer
• B. McMurray’s and Apley’s
• C. Varus stress test (LCL) and valgus stress test (MCL)
• D. Clarke’s test and Godfrey’s sign

Answer: (C)

Testing the collateral ligaments of the knee relies on applying sideways forces to the tibia while the thigh is stabilized, looking for abnormal widening or laxity. The valgus stress test applies a medial force to stress the medial collateral ligament, while the varus stress test applies a lateral force to stress the lateral collateral ligament. Performing these at appropriate knee flexion (often around 20–30 degrees) helps isolate the MCL and LCL from the cruciate ligaments. Therefore, this pair of tests best assesses the collateral ligaments.

The other tests target different structures: Lachman and Anterior Drawer assess the anterior cruciate ligament; McMurray’s and Apley’s tests evaluate meniscal pathology; Clarke’s test and Godfrey’s sign relate to patellofemoral issues and posterior knee sag/PCL involvement.