Ask your patient to lie in a supine posture.
The patient's ankle joint should be in 20deg of plantarflexion. Stabilize the anterior side of the distal leg (distal fibula and tibia) with one hand.
Next, cup the palm of a second hand and grab the patient's calcaneus, and make an attempt to bring the calcaneus anteriorly observing the total amount of anterior translation in the lateral portion of the ankle and the difference in the end feel.
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