With the knee flexed at 90 degrees, which of the following tests would be least likely performed?

• A. Anterior drawer test
• B. Ely's test
• C. Craig's test
• D. Posterior sag sign

Answer: (B)

With the knee at 90 degrees, several knee tests are commonly used because that angle puts the ligaments and joint structures in a position that makes abnormal motion or laxity easy to observe. The anterior drawer test uses that 90-degree flexion to assess ACL integrity by looking at anterior tibial translation. The posterior sag sign also relies on the knee being flexed around 90 degrees to let gravity show a sag of the tibia when the PCL is compromised. Craig’s test for femoral anteversion is performed with the knee flexed to 90 degrees to stabilize the limb while the tibia is rotated to find the neutral point. Ely’s test, on the other hand, is about rectus femoris tightness and requires moving the knee through flexion from extension to a greater bend to elicit a hip motion. If the knee is already fixed at 90 degrees, you can’t complete the necessary knee flexion movement for Ely’s test, so it’s least likely to be performed in that position.