Superficial transverse metatarsal ligament

At a glance

English

Superficial transverse metatarsal ligament

Latin (TA2)

Ligamentum metatarseum transversum superficiale

System

Muscle

Region

Lower limb

Side

Paired, left and right

About the superficial transverse metatarsal ligament

The superficial transverse metatarsal ligament is a set of thin transverse fibres in the front of the sole, lying in the superficial fascia under the heads of the metatarsals. It runs across the bases of the toes, linking the forward slips of the plantar aponeurosis just before they divide to reach each toe. It is a separate, more superficial structure from the stronger deep transverse metatarsal ligament, which joins the plantar plates of the metatarsophalangeal joints.

Its fibres are woven into the skin and fat of the ball of the foot and into the digital slips of the plantar aponeurosis. Between the slips, under the ligament, pass the digital nerves and vessels heading for the toes, and the lumbrical tendons run nearby. Further back, the long flexor tendons travel beneath the deep ligament, while the interosseous tendons pass above it. The two transverse bands therefore form layered ties across the forefoot.

These fibres help hold the plantar aponeurosis and the skin of the forefoot together, limiting splaying of the soft tissues under load and anchoring the skin of the ball of the foot so that it does not slide when pushing off. They also give a firm roof over the spaces through which the toe nerves and vessels pass. In the hand, a comparable superficial band lies in the palm at the bases of the fingers.

Where the plantar digital nerves pass between the metatarsal heads, close to these bands, a nerve can be squeezed and thickened, giving burning pain between the third and fourth toes known as Morton's neuroma, although the deep ligament is the band most often blamed. The ligament has no muscle of its own; it is tensed indirectly when the toes are pulled up, through its links with the plantar aponeurosis.

Attachments, action and supply

Origin

Digital slips of the plantar aponeurosis and the skin under the metatarsal heads, on the medial side of the forefoot.

Insertion

The corresponding slips and skin on the lateral side, crossing beneath all five metatarsal heads.

Action

Ties the forward parts of the plantar aponeurosis and the forefoot skin together, steadying the soft tissues of the ball of the foot.

Nerve supply

Plantar digital branches of the medial and lateral plantar nerves supply the overlying skin.

Blood supply

Plantar digital and plantar metatarsal arteries.