Lateral talocalcaneal ligament

At a glance

English

Lateral talocalcaneal ligament

Latin (TA2)

Ligamentum talocalcaneum laterale

System

Ligament

Region

Foot

Side

Paired, left and right

About the lateral talocalcaneal ligament

The lateral talocalcaneal ligament is one of the small ligaments that strengthen the capsule of the subtalar joint, the articulation between the underside of the talus and the top of the calcaneus. It is a compact, tough bundle of fibres on the lateral side of the hindfoot, just below the ankle. Its upper end is fixed to the outer face of the talus immediately under the facet that meets the lateral malleolus, and its fibres run down and slightly backwards to the outer face of the calcaneus.

Its closest neighbour is the calcaneofibular ligament, which comes down from the tip of the lateral malleolus. The two run parallel, but the talocalcaneal band sits a little in front of the calcaneofibular ligament and on a deeper plane, closer to the bones. The tendons of fibularis longus and brevis pass behind and below both on their way round the lateral malleolus, and the sinus tarsi opens just in front.

The subtalar joint is where most inversion and eversion of the foot take place. Its main stabiliser is the strong interosseous talocalcaneal ligament in the sinus and tarsal canal, helped by the cervical ligament. The lateral, medial and posterior talocalcaneal ligaments are thinner capsular reinforcements that hold the two bones together at the margins of the joint and resist excessive gapping.

An inversion sprain of the ankle most often tears the anterior talofibular ligament first and the calcaneofibular ligament next. When the force is greater, the lateral talocalcaneal ligament may also give way, and this contributes to instability of the subtalar joint that can follow repeated sprains. Such instability is easy to confuse with ankle instability, and both may be present.

Attachments and function

Attaches from

The outer face of the talus, just below its facet for the lateral malleolus.

Attaches to

The outer face of the calcaneus, in front of the calcaneofibular ligament.

Function

Reinforces the lateral capsule of the subtalar joint and helps limit excessive inversion and separation of the talus from the calcaneus.

Nerve supply

Articular twigs of the sural nerve and the deep fibular nerve supply the lateral side of the subtalar joint.

Blood supply

Branches of the fibular (peroneal) artery and the lateral tarsal artery.