Intrinsic foot muscles are responsible for movement of the ankle and foot

Ankle anatomy

The ankle joint, also known as the talocrural joint, allows dorsiflexion and plantar flexion of the foot. It is made up of three joints: upper ankle joint (tibiotarsal), talocalcaneonavicular, and subtalar joints. The last two together are called the lower ankle joint.

The upper ankle joint is formed by the inferior surfaces of tibia and fibula, and the superior surface of talus. The lower ankle joint is formed by the talus, calcaneus, and navicular bone. The joint is supported by a set of ankle ligaments: the medial collateral or deltoid ligament, and lateral collateral ligament.

We’ve got you covered with everything you need to know about the ankle joint and its ligaments with these study units:

Bones of the foot

There are 26 bones in the foot, divided into three groups:

• Seven tarsal bones
• Five metatarsal bones
• Fourteen phalanges

Tarsals make up a strong weight bearing platform. They are homologous to the carpals in the wrist and are divided into three groups: proximal, intermediate, and distal. 

Learn the bones of the foot in half the time with these interactive quizzes and labeling activities!

• The proximal tarsal bones are the talus and calcaneus. 
• The intermediate tarsal bone is the navicular. 
• The distal tarsals are the cuboid and three cuneiform bones (lateral, intermediate, and medial).

A useful mnemonic in order to remember the tarsal bones is the following:

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• Talus
• Calcaneus
• Navicular
• Medial cuneiform
• Intermediate cuneiform
• Lateral cuneiform
• Cuboid

Quiz yourself on the foot bones in multiple difficulty levels with this quiz.

The easiest way to learn all about the tarsal bones is to review them one by one. You can do that with our additional resources:

Metatarsals are homologous to the metacarpals​​​​​​​ of the hand. They are involved in supporting body weight. On the plantar surface of the head of the 1st metatarsal, we see two prominent sesamoid bones (a medial and a lateral one). 

Phalanges also parallel the hand, the lateral four toes are made up of three phalanges (proximal, middle, and distal). Whilst the great toe (hallux) is comprised of only two phalanges (proximal and distal).

We encourage you to take a look at our study materials to find out more about the bones of the foot and foot ligaments.

Joints of the foot

Besides the ankle joint which connects the foot with the leg, the bones of the foot articulate among themselves through many synovial joints. There are four groups of foot joints: intertarsal, tarsometatarsal, metatarsophalangeal, and interphalangeal. 

• The intertarsal joints are between the tarsal bones. These joints are the subtalar (talocalcaneal), talocalcaneonavicular, calcaneocuboid, cuneonavicular, cuboideonavicular, and intercuneiform joints. 
• Tarsometatarsal joints are the articulations between the tarsals and metatarsals.
• Metatarsophalangeal joints (MTP) are the joints between the heads of metatarsals and corresponding bases of the proximal phalanges of the foot. 
• Interphalangeal joints are between the phalanges of the foot. The great toe has only one interphalangeal joint, while the other four toes have a proximal (PIP) and a distal (DIP) interphalangeal joint.

Muscles of the foot

Foot muscles contribute to eversion and inversion of foot, movements of the toes, as well as plantar flexion and dorsiflexion. We encourage you to go through this study unit to learn all about the foot muscles.

The foot muscles are divided into plantar and dorsal groups. There are only two muscles in the dorsal group, while the plantar muscles are further subdivided into three groups; lateral, central, and medial. 

The dorsal foot muscles are in the dorsum of foot and they extend the toes. They are the extensor digitorum brevis and extensor hallucis brevis muscles.

The plantar foot muscles are divided into three groups of muscles by the deep fasciae of the foot: lateral, central, and medial. Note that plantar muscles can also be studied as four layers, but here they are presented as groups.

The lateral plantar muscles act upon the fifth toe. They are the abductor digiti minimi, flexor digiti minimi brevis, and opponens digiti minimi muscles. 

Central plantar muscles act upon the lateral four toes. They are the flexor digitorum brevis, quadratus plantae, four lumbricals, three plantar interossei, and four dorsal interossei muscles.

Medial plantar muscles act upon the great toe, or hallux. They are the abductor hallucis, adductor hallucis, and flexor hallucis brevis muscles. Note that adductor hallucis is anatomically located in the central compartment of foot, but it is functionally grouped with the medial plantar muscles due to its actions on the great toe (hallux).

Note that tendons in the foot are protected with tendon sheaths. We can help you with both tendons sheaths and with medial plantar muscles.

Check out these study resources:

To master all lower limb muscles, check out this muscle anatomy reference chart with high-quality illustrations. It provides a quick reference to lower limb muscle origins, insertions, innervations and functions.

What's the best way of learning anatomy? Repetition for sure. And how to make repetition interesting? With Kenhub custom quizzes! Test your knowledge about the ankle and foot anatomy with our quiz specially designed to aim the bones, ligaments, joints, muscles and neurovasculature of this region.

Sources

All content published on Kenhub is reviewed by medical and anatomy experts. The information we provide is grounded on academic literature and peer-reviewed research. Kenhub does not provide medical advice. You can learn more about our content creation and review standards by reading our content quality guidelines.

Article, review and layout:

• Jana Vaskovic
• Alexandra Osika
• Nicola McLaren

Illustrations:

• Ankle and foot (left lateral view) - Liene Znotina
• Ankle joint (overview) - Paul Kim
• Bones and ligaments of the foot (diagram) - Liene Znotina
• Muscles of the foot (overview) - Liene Znotina