Metatarsal bones

Metatarsal Bones

The metatarsal bones are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, they are numbered from the medial side (side of big toe): the first, second, third, fourth, and fifth metatarsal (often depicted with Roman numerals).

Structure

Each metatarsal bone is a long bone, being broad and concave at the proximal end, tapering down to the distal end. The body of the metatarsal is prismoid in form, tapers gradually from the tarsal to the phalangeal extremity, and is curved longitudinally, so as to be concave below, slightly convex above.

First Metatarsal

The first metatarsal bone is the thickest and shortest of the metatarsal bones. It is designed to bear more weight than the other metatarsals, and its unique structure is adapted to take on this role.

Second to Fifth Metatarsals

The second metatarsal bone, third metatarsal bone, fourth metatarsal bone, and fifth metatarsal bone are all long bones, each with a base, shaft, and head. The base is the part of the bone that is closest to the ankle, the shaft is the long, slender part of the bone, and the head is at the end of the bone that is closest to the toe.

Function

The metatarsal bones are crucial for balance and propulsion during walking and running. They work together with the tarsal bones to provide a stable platform for the body, and with the phalanges to provide leverage for the toes.

Clinical Significance

Injuries to the metatarsal bones are common and can include fractures, dislocations, and stress fractures. These injuries are often caused by direct trauma, overuse, or systemic diseases such as osteoporosis.

See Also

• Foot
• Bone fracture
• Osteoporosis