Ligament · Ankle

Deltoid ligament

Ligamentum collaterale mediale

A strong triangular fan on the inner ankle, spreading from the medial malleolus down onto the talus, calcaneus and navicular. It is much tougher than the lateral ligaments and resists the ankle rolling outward, so it is injured far less often — when it does fail, the force involved is usually enough to break bone as well.