What Is the Heel Bone?

The heel bone is called the calcaneus, a word that comes from "calc," meaning stone or chalk.

Shape

• The calcaneus is a short bone of the tarsal, or ankle group, and the largest bone of that group. The posterior end of the calcaneus is the tuberosity of the calcaneus, which is the heel that you feel outside your foot.

Tendon

• The tuberosity of the calcaneus is where the calcaneal (Achilles) tendon attaches the bone to the calf muscles.

Connection to Leg

• The calcaneus does not articulate directly with the tibia, or leg bone. Above the calcaneus sits the talus, another tarsal bone. It's superior surface is called the trochlear surface of the talus, and this articulates with the leg.

Arches

• Arches keep the sole of the foot from resting flat on the ground. Two of the three arches spring from the heel bone. The medial longitudinal arch goes from the heel to the great toe. The lateral longitudinal arch goes from the heel to the little toe. The third arch, the transverse arch, crosses the tarsal bones just proximal (closer to the body) to the phalanges (toe bones).

Evolution

• The human calcaneus is much larger and more developed that that of the chimpanzee, since humans support their entire body weight on their feet.