Plantar metatarsal ligaments

At a glance

English

Plantar metatarsal ligaments

Latin (TA2)

Ligamenta metatarsea plantaria

System

Ligament

Region

Foot

Side

Paired, left and right

About the plantar metatarsal ligaments

The plantar metatarsal ligaments are small fibrous bands on the underside of the forefoot, close to the tarsometatarsal line. Each one passes across from the plantar side of the base of one metatarsal to the base of its neighbour, so they link the second to the third, the third to the fourth and the fourth to the fifth. Where the bases meet, they form small plane synovial joints, the intermetatarsal joints, whose cavities usually open into those of the tarsometatarsal joints just behind.

Each of these joints is held by a set of three bands: a plantar ligament on the underside, a dorsal metatarsal ligament on the upper side, and an interosseous ligament between the facing rough surfaces of the bases, which is the strongest of the three. The bases of the first and second metatarsals are usually not joined in this way. Instead, the second metatarsal base is anchored to the medial cuneiform by a strong interosseous band, the Lisfranc ligament, so the first ray can move more freely than the others.

The ligaments lie deep in the sole, above the interosseous muscles and the deep plantar arch, and close to the tendon of fibularis longus as it runs obliquely towards the first metatarsal. They are distinct from the plantar plates of the metatarsophalangeal joints and from the deep transverse metatarsal ligaments, which join the heads of the bones further forwards.

By tying the bases into a firm unit, the ligaments help shape and maintain the transverse arch at the level of the forefoot and allow only slight gliding between the bones. They are torn in tarsometatarsal (Lisfranc) fracture-dislocations, where the metatarsal bases may move apart or shift together to one side.

Attachments and function

Attaches from

The plantar side of the bases of the second, third and fourth metatarsals.

Attaches to

The plantar side of the base of the neighbouring metatarsal on the lateral side, from the third to the fifth.

Function

Bind the metatarsal bases together, strengthen the intermetatarsal joints from below and help maintain the transverse arch.

Nerve supply

Articular branches of the lateral plantar nerve, mainly its deep branch.

Blood supply

Branches of the deep plantar arch and plantar metatarsal arteries.