Which special test is used to assess posterior cruciate ligament (PCL) pathology by evaluating posterior tibial translation?

Which special test is used to assess posterior cruciate ligament (PCL) pathology by evaluating posterior tibial translation?

• A. Anterior drawer test
• B. Posterior drawer test
• C. Lachman test
• D. External rotation test

Answer: (B)

The main idea is that the PCL’s job is to limit backward movement of the tibia relative to the femur. The posterior drawer test assesses this exact motion. With the knee bent to about 90 degrees and the femur stabilized, you push the tibia backward. A normal knee shows only a small amount of posterior movement with a firm end feel. If the PCL is torn or lax, the tibia will translate more posteriorly than normal, giving a positive finding. This test specifically targets posterior tibial translation, which is why it best identifies PCL pathology. By contrast, pulling the tibia forward evaluates the ACL, and the external rotation test mainly screens the posterolateral corner structures rather than posterior tibial translation.

The main idea is that the PCL’s job is to limit backward movement of the tibia relative to the femur. The posterior drawer test assesses this exact motion. With the knee bent to about 90 degrees and the femur stabilized, you push the tibia backward. A normal knee shows only a small amount of posterior movement with a firm end feel. If the PCL is torn or lax, the tibia will translate more posteriorly than normal, giving a positive finding. This test specifically targets posterior tibial translation, which is why it best identifies PCL pathology. By contrast, pulling the tibia forward evaluates the ACL, and the external rotation test mainly screens the posterolateral corner structures rather than posterior tibial translation.