The calcaneus (latin: calcaneus, calcaneum; meaning “heel”) is the large bone forming the heel. The calcaneus articulates with both the cuboid and the talus bones.
There are several important landmarks on the calcaneus, such as:
- calcaneal tuberosity,
- calcaneal sulcus,
- sustentaculum tali,
- tarsal sinus (formed together with the talus).
The calcaneal tuberosity is the posterior thickened part of the calcaneus.
The calcaneal sulcus is a groove between the superior articular surfaces of the calcaneus.
The sustentaculum tali (the talar shelf) is a support for the calcaneus, directed medially. It gives attachment to the plantar calcaneonavicular ligament, tibiocalcaneal ligament, and medial talocalcaneal ligament.
The tarsal sinus is an indentation formed by the sulcus tali and the calcaneal sulcus.
The articular surfaces of the calcaneus include:
- superior articular surfaces,
- anterior articular surface.
The superior articular surfaces of the calcaneus (anterior, middle, posterior) are the three surfaces of the calcaneus that articulate with the talus.
The anterior articular surface is the surface of the calcaneus which articulates with the cuboid bone.