Which bone forms part of the ankle joint together with the tibia and fibula?

• A. Calcaneus
• B. Navicular
• C. Talus
• D. Cuboid

Answer: (C)

The ankle joint proper (talocrural joint) is formed where the distal ends of the tibia and fibula meet the superior surface of the talus. This bone sits between the leg bones and the rest of the foot, acting as the hinge that enables dorsiflexion and plantarflexion. The other bones listed have important roles elsewhere: the calcaneus forms the subtalar joint with the talus (the heel and side-to-side movements) and the navicular and cuboid help form the midfoot joints with the talus and metatarsals, but they do not form the ankle joint with the tibia and fibula. So the bone that forms part of the ankle joint with the tibia and fibula is the talus.