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beginnerSource-checked11 min read

The Ankle & Foot: An Overview

The body's base of support — the subtalar joint, the foot's arches, and its small intrinsic muscles.

Before this: The Lower Legs: An Overview

You will be able to

  • Distinguish the ankle joint (up/down motion) from the subtalar joint (side-to-side tilt).
  • Name the two key foot bones introduced in this region and their role in the subtalar joint.
  • Describe the general role of the intrinsic foot muscles.
Simplified side view of the ankle and foot showing the talus sitting beneath the tibia and fibula, the calcaneus (heel bone) below it forming the subtalar joint, and the arch of the foot extending forward to the toes.
Ankle & foot — talus, calcaneus, and subtalar joint (simplified). A beginner-level schematic of the ankle and foot's key bones: talus and calcaneus, forming the subtalar joint.
Illustration: Anatomy Learning Platform (original) · CC0-1.0 (public domain dedication)

⚠ Safety note

Significant swelling, bruising, inability to bear weight, or visible deformity after an ankle injury needs prompt medical evaluation. A trainer coaches balance and mobility work; they do not diagnose fractures or sprains.

Two joints, two directions

The foot's motion comes from two stacked joints working together:

  • The ankle joint (talocrural), covered in the Lower Legs region, hinges the foot up and down.
  • The subtalar joint, between the talus and calcaneus, tilts the foot side to side

(inversion and eversion).

Together, they let the foot both push off powerfully in a straight line and adapt to uneven or angled ground.

Small muscles, big stabilizing role

The intrinsic foot muscles live entirely within the foot itself, supporting the arches and fine-tuning balance — distinct from the calf and shin muscles, which start in the lower leg and only reach into the foot via long tendons.

Why ankle sprains are so common

Because the subtalar joint allows the foot to tilt, and because the outer ankle ligaments are relatively thin compared to the inner ones, rolling the ankle inward (inversion) is one of the most common sport and exercise injuries.

Sources for this lesson

“Ankle sprains are among the most common exercise and sport injuries.”

National Institute of Arthritis and Musculoskeletal and Skin Diseases — NIH / NIAMS · Sports Injuries

Government / official guideline · License: Public domain (U.S. government work) unless otherwise noted. · Last checked 2026-07-19

“The subtalar joint (talus and calcaneus) allows inversion and eversion of the foot, distinct from the ankle joint's flexion/extension.”

Anatomy and Physiology 2e — OpenStax, Rice University · Ch. 9.5 Synovial Joints

Peer-reviewed textbook · License: CC BY-NC-SA 4.0 · Last checked 2026-07-19

Take the quiz (3 questions)Explore the Ankles & Feet

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