Metatarsal bones

Structure

The five metatarsals are dorsal convex long bones consisting of a shaft or body, a base (proximally), and a head (distally). The body 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. The base or posterior extremity is wedge-shaped, articulating proximally with the tarsal bones, and by its sides with the contiguous metatarsal bones: its dorsal and plantar surfaces are rough for the attachment of ligaments. The head or distal extremity presents a convex articular surface, oblong from above downward, and extending farther backward below than above. Its sides are flattened, and on each is a depression, surmounted by a tubercle, for ligamentous attachment. Its plantar surface is grooved antero-posteriorly for the passage of the flexor tendons, and marked on either side by an articular eminence continuous with the terminal articular surface.

During growth, the growth plates are located distally on the metatarsals, except on the first metatarsal where it is located proximally. Yet it is quite common to have an accessory growth plate on the distal first metatarsal.

Articulations

The base of each metatarsal bone articulates with one or more of the tarsal bones at the tarsometatarsal joints, and the head with one of the first row of phalanges at the metatarsophalangeal joints. Their bases also articulate with each other at the intermetatarsal joints

• The first metatarsal articulates with the medial cuneiform, and to a small extent to the intermediate cuneiform.
• the second with all three cuneiforms.
• the third with the lateral cuneiform.
• the fourth with the lateral cuneiform and the cuboid.
• The fifth with the cuboid.

Muscle attachments