Foot and Ankle Anatomy

The foot is a very complicated structure. This page provides numerous foot anatomy images, including illustrations of the bones, muscles, tendons, ligaments in the foot and ankle, and descriptions of the structures.

The inside (medial), outside (lateral) and front (anterior), and back of the foot (posterior) are shown in the image below. In the first view, titled medial view, the inside of the arch and ankle are shown. You can see the origin of the plantar fascia, which is a common area of heel pain.

The great toe and the posterior tibial tendon are also shown. Pain at the inside of the arch can be due to posterior tibial tendonitis. The second view, titled lateral, shows the outside of the foot. The peroneal brevis tendon insertion is labeled, and this is a common area of pain in peroneal tendonitis.

Avulsion fractures of the base of the 5th metatarsal will also have pain in this area. In the third view of the front of the foot, titled anterior, the common area of nerve impingement is labeled.

The great toe is also labeled. The most common problem at the great toe is a bunion. Osteoarthritis is also common in the great toe joint, the 1st metatarsal phalangeal joint. The last image shows the back of the foot, also known as the posterior aspect, and the Achilles tendon and its insertion are labeled. The two areas labeled are the common areas of pain in Achilles tendonitis.

Below are diagrams of the foot’s orientation, common anatomical foot structures, and common foot problems associated with these structures.

anatomy foot medial labeled

Medial

anatomy foot lateral

Lateral

anatomy foot anatomy

Anterioranatomy posterior labeled

Posterior

Foot Bones

Bones in the Foot: Top View

A labeled diagram of the bones in the foot is shown below. This view is from the top of the foot.

Anatomy bones of the foot labeled A. distal phalanx of the hallux.

 

Foot Bones

B. proximal phalanx of the hallux
C. distal phalanges
D. intermediate phalanges
E. proximal phalanges
F. 1st metatarsal
G. lesser metatarsals
H. medial cuneiform
I. intermediate cuneiform
J. lateral cuneiform
K. styloid process
L. cuboid
M.navicular
N. talus
O. calcaneus

Bones in the Foot: Bottom View

A labeled diagram of the bones in the foot is shown below. This view is from the bottom of the foot, a plantar view. Ligaments attaching to the bones are also shown but not labeled in this diagram.

Foot anatomy bones plantar view labeled A. distal phalanx of the hallux

B. proximal phalanx of the halluxanatomy-bones-plantar
C. distal phalanges
D. intermediate phalanges
E. proximal phalanges
F. 1st metatarsal
G. lesser metatarsals
H. medial cuneiform
I. intermediate cuneiform
J. lateral cuneiform
K. styloid process
L. cuboid
M. navicular
N. talus
O. calcaneus
P. sesamoid

Common structural foot problems that develop at the metatarsal phalangeal joints include bunions and hammertoes.

Bones in the Foot: Side View Anatomy

This is a view of the foot looking at the foot from the side. The foot bones are labeled with the pronunciation given. Note that there are two accessory bones labeled that do not occur in all feet; they are the os peroneum, which can occur on the outside of the cuboid, and the os vesalianum, which occurs at the base of the 5th metatarsal.

Foot anatomy, bones labeled lateral view

A. fibulaBones in the Foot: Side View Anatomy
B. tibia
C. talus
D. navicular
E. cuneiforms
F. calcaneus
G. cuboid
H. os peroneum
I. os vesalianum
J. styloid process
K. 5th metatarsal
L. 5th metatarsal phalangeal joint
M. phalanges

Tendons on the Top of the Foot

A tendon is a structure that connects the muscle to the bone. It can be described as a cord or a band of connective tissue. The extensor hallucis longus originates in the front of the leg and travels down the ankle to attach to the big toe.

The function is to pull up the big toe (extend) and pull up the ankle (dorsiflex). The extensor digitorum longus originates in the front of the legs, travels across the ankle, and inserts on all the toes. This tendon pulls the toes up (extend) and pulls up the ankle (dorsiflex).

The extensor digitorum brevis is a small muscle that originates on the top of the heel bone and extends out to the digits. The extensor digitorum brevis pulls the toes up (extends the toes).

Image of tendons on the top of the foot

TendonsA. Extensor hallucis longus

B. Extensor digitorum longus

C. Extensor digitorum brevis

Tendons on the Bottom of the Foot

The image below shows the flexor hallucis longus, the flexor digitorum brevis, flexor digitorum longus, and posterior tibial tendon. The flexor hallucis longus originates in the back of the leg, crosses the ankle, and inserts on the base of the small bone in the big toe.

Its action is to bend the big toe down (flex) and bend the ankle down (plantarflex). The flexor hallucis brevis is a small muscle that originates from the small bones on the bottom of the foot and inserts into the base of the big toe. Its action is to bend the big toe down (flex).

The flexor digitorum longus originates in the back of the leg, crosses the ankle, and inserts on the tips of the toes. Its action is to bend the toes down (flex) and bend the ankle down (plantarflex). The posterior tibialis originates in the back of the leg, crosses the ankle, and inserts on the navicular and the bottom of the midfoot within the arch.

The action of the posterior tibialis is to bend the ankle down (plantarflex) and support the arch (supinate). Learn more about an ankle sprain.

Image of tendons on the bottom of the foot, flexor tendons

A. Flexor hallucis longusTendons on the Bottom of the Foot

B. Flexor hallucis brevis

C. Flexor digitorum longus

D. Posterior tibialis

The most common foot condition associated with tendons is tendinitis, also referred to as tendinosis or tendinopathy—more information on tendonitis/tendinosis, posterior tibial tendonitis, and phases of tendon healing.

Plantar Fascia

Plantar FasciaThe plantar fascia is a long ligament-type structure that supports the longitudinal arch when walking. The medial, central, and lateral bands are three bands, as shown in the image to the right. The fascia originates on the heel bone, called the calcaneus, and extends to insert into the bottom of the toes.

The plantar fascia is one of the main structures that support the arch. In those with faulty foot mechanics, most commonly overpronation, the plantar fascia can become over-stressed, stretched, and torn, leading to inflammation, pain, and eventual degeneration in a condition known as plantar fasciitis.

Big Toe Joint

The big toe joint is called the 1st metatarsal phalangeal joint or the 1st MPJ. The hallux consists of the distal phalanx and proximal phalanx and is essentially the big toe. The lateral collateral and sesamoid ligaments help to stabilize the joint. The sesamoid is a small bone under the great toe.

Big Toe Joint

Toenail Anatomy

The main function of the toenail is to protect the toes. The nail unit, shown to the right, comprises the nail plate, nail fold, lunula, cuticle, and hyponychium.

The nail plate is known to most as simply the “nail.” The nail plate is composed of a translucent protein called keratin. The nail plate is porous to water, and the water content is directly related to its brittleness or hardness. It does not contain any blood vessels or nerves.

Toenail Anatomy

The matrix is the nail root and the sole structure responsible for the formation and growth of the nail plate. The nail root sits beneath the proximal nail fold.

The cuticle, also known as the eponychium, is formed from cells from the proximal nail fold; the cuticle attaches to the nail plate, acting as a natural seal to protect the proximal nail fold from microbial invasion.

The lunula is a crescent-shaped white zone at the base of the nail, which represents the furthest extension of the nail root.

The nail bed extends from the lunula to the hyponychium and supports the nail plate in its contour, but it does not assist with the growth of the nail plate.

Conclusion