The posterior drawer test for the ankle identifies which condition?

• A. Anterior talus displacement
• B. Syndesmotic instability only
• C. Tibiofibular translation
• D. Posterior displacement of the talus on the tibia

Answer: (D)

The test targets posterior stability of the ankle by assessing posterior translation of the talus relative to the tibia. When you perform it, you are forcing the talus to move backward within the ankle mortise; a positive result means there is excess posterior movement, indicating laxity or injury of the structures at the back of the joint (posterior talofibular ligament and posterior capsule). This is why the finding is described as posterior displacement of the talus on the tibia.

This differs from anterior drawer findings (which assess anterior displacement), from tests of syndesmotic instability (which focus on the distal tibiofibular relationship with different maneuvers), and from measures of tibiofibular translation (which look at movement between the two leg bones rather than the talus within the mortise).