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Relevant Foot Anatomy

Understanding relevant foot anatomy is important if you want to understand different disorders and diseases of the foot.

The foot is one of the most important but frequently neglected parts of the body.

Knowing the bones of the foot is vital to understand foot anatomy.内蒙古医科大学第二附属医院手足显微外科诊疗中心景尚斐

Your foot consists of 28 bones. These are

7 tarsal bones

calcaneus

talus

medial cuneiform

intermediate cuneiform

lateral cuneiform

cuboid

navicular

5 metacarpal bones (1st, 2nd, 3rd, 4th, 5th from great toe to little toe respectively)

5 proximal phalanges (1st, 2nd, 3rd, 4th, 5th from great toe to little toe respectively)

4 middle phalanges (2nd, 3rd, 4th, 5th from second toe to little toe respectively)

5 distal phalanges (1st, 2nd, 3rd, 4th, 5th from great toe to little toe respectively)

2 sesamoid bones below the 1st metacarpal head

Talus bone joins the foot to the leg. It consists of three parts a head, neck and body. No muscles attach to this bone. It articulates with the navicular, calcaneum and the tibia and fibula forming the talo-navicular, talo-calcaneal (subtalar)and ankle joints respectively.

Calcaneus in the largest tarsal bone. It forms the heel of the foot. It provides important attachment to the Achilles tendon and flexor muscles of the lesser toes. It articulates with the talus and cuboid bones forming the talo-calcaneal and the calcaneo-cuboid joints.

Navicular bone articulates with the head of the talus and the cuneiform bones. It provides important attachment to the tibialis posterior muscle.

Cuboid bone articulates with the 4th and 5th metatarsal bones and with the calcaneus forming the calcaneo-cuboid joint.

The cuneiform bones articulate with the 1st, 2nd and the 3rd metatarsal bones.

The metatarsal and phalangeal bones form the toes of the foot.

The metatarsal bones consist of a base, a shaft and a head. The base articulates with the cuneiform and the cuboid bones. The head articulates with the base of the proximal phalanges.

The important muscles of the foot and their functions are

Gastrosoleus (calf) muscles plantar-flex (stand on your toes) the foot.

Tibialis anterior muscle dorsi-flexes (pull your toes up) the foot.

Both the above movements occur at the ankle joint.

Tibialis anterior and posterior are responsible for inversion (move the foot inwards) of the foot.

Peroneus longus and brevis are responsible for eversion (move the foot outwards) of the foot.

Both these movements occur at the talo-calcaneal (subtalar) joint.

Extensor muscles are responsible for extension movement of the toes.

Flexor muscles are responsible for flexion movement of the toes.

Foot anatomy includes the arches of the foot that are two in number

longitudinal arch

transverse arch

The longitudinal arch is more developed on the inner side of the foot as compared to the outer side where it is almost flat. The apex of the arch is the talus bone. Posterior pillar is the calcaneus bone. Anterior pillar is formed by tarsal and metatarsal bones.

Anterior pillar is again divided into a medial (inner) column and a lateral (outer) column. Medial column is formed by navicular, cuneiform and 1st, 2nd and 3rd metatarsal bones. Lateral column is formed by cuboid and 4th and 5th metatarsal bones.

Transverse arch is best developed at the junction of the metatarsal bones with the cuboid and cuneiform bones.

The function of the arches of the foot is to transmit the weight of the body adequately while walking on even or uneven surfaces.

Another important aspect of foot anatomy is the blood supply of the foot which comes from three arteries. These are

Anterior Tibial

Posterior Tibial

Peroneal Artery

The anterior tibial artery is a branch of the politeal artery. Popliteal artery then continues down wards and divides into the peroneal and posterior tibial arteries.

Anterior tibial artery supplies blood to the front of the leg. Posterior tibial supplies blood to the posterior and inner parts of the leg. Peroneal artery supplies blood to the outer aspect of the leg.

Anterior tibial artery continues downwards and its pulse can be palpated in front of the ankle joint. In the foot it continues as the dorsalis pedis artery. Pulse of this artery can be felt just proximal to the first web space. Dorsalis pedis artery gives off a arcuate artery that along with its branches supplies the outer four toes. The dorsalis pedis artery continues down to supply the great toe.

The posterior tibial artery passes behind the ankle then winds down to the inner side. Here its pulse can be felt behind the medial malleoli. Moving towards the sole of the foot it divides into two branches called the lateral and medial plantar arteries that supply the sole.

The peroneal artery descends down and divides into branches that supply the posterior and outer aspect of the heel.