Anatomy Guide › Lower limb

Calcaneus

Lower limb · Foot

The heel bone — the largest bone of the foot, your landing gear and the anchor of the Achilles tendon.

The calcaneus is the heel: the largest, sturdiest bone of the foot and the first part of you to strike the ground in a normal walking stride. It juts backward beneath the ankle like the rear pillar of an arch, forming the posterior anchor of the foot's structure, while the talus rides on its upper surface handing down the body's weight.

Its most famous feature attaches at the back: the Achilles tendon, the thickest and strongest tendon in the body, cables the calf muscles to the calcaneus. Every step, jump, and sprint ends with the calf pulling on this bone to lever the body forward over the toes — a system that can transmit forces of several times body weight. The bone's underside bears a broad pad of specialized fat, honeycombed into pressure-absorbing chambers, which is why heels tolerate a lifetime of impacts.

The calcaneus's troubles are as characteristic as its strengths. Plantar fasciitis — the stabbing morning heel pain familiar to runners and people who stand all day — is an irritation where the sole's fibrous band anchors to the calcaneus, sometimes accompanied by a bony 'heel spur.' Falls from height write a different story: landing on the feet can crush the calcaneus, an injury so linked to falls that emergency doctors who see it immediately check the spine, which often takes the same axial force.

In Anamo, the calcaneus holds down the rear corner of the foot map. Achilles above, plantar structures below, talus and cuboid ahead — heat readings around the heel resolve quickly once you know its neighbors.

Quick facts

Think you could find the calcaneus on a 3D model? Play Anamo and test yourself — every guess is color-coded by how close it lands to the mystery structure.

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