Anterior tibiofibular ligament

At a glance

English

Anterior tibiofibular ligament

Latin (TA2)

Ligamentum tibiofibulare anterius

System

Ligament

Region

Foot

Side

Paired, left and right

About the anterior tibiofibular ligament

Just above the ankle the lower ends of the tibia and fibula are held tightly together at a fibrous joint, the tibiofibular syndesmosis. The fibula sits in a notch on the outer side of the tibia, and the two bones must stay clasped around the talus for the ankle to work. Four structures hold them: the anterior and posterior tibiofibular ligaments, the deep interosseous ligament and the lower part of the interosseous membrane. The anterior tibiofibular ligament, also called the anterior inferior tibiofibular ligament, covers the front of the joint.

It is a flat, trapezoid-shaped band, wider below than above. Its fibres begin on the front edge of the fibular notch at the anterior tubercle of the tibia and pass downwards and outwards to the front border of the lateral malleolus. Its lowest part, sometimes a separate bundle, reaches down far enough to touch the cartilage on the side of the talus when the foot is bent upwards.

In front it is covered by the tendon of fibularis tertius, the deep fascia of the leg and the skin. Behind it lies the interosseous ligament, which fills the space between the bones. The perforating branch of the fibular artery passes nearby.

The syndesmosis lets the fibula move slightly up, down and outwards as the wide front of the talus wedges between the malleoli during dorsiflexion. The anterior ligament restrains this spread. A twisting injury that forces the foot outwards can tear it, a so-called high ankle sprain, which heals more slowly than an ordinary sprain. If the syndesmosis is fully disrupted the mortise widens and the injury may need screw or suture fixation; a tear combined with a high fibular fracture is called a Maisonneuve injury.

Attachments and function

Attaches from

The anterior tubercle of the tibia at the front margin of the fibular notch.

Attaches to

The anterior border of the lateral malleolus.

Function

Holds the lower ends of the tibia and fibula together across the front of the syndesmosis and resists the malleoli spreading apart.

Nerve supply

Branches of the deep fibular nerve.

Blood supply

The perforating branch of the fibular artery and the anterior lateral malleolar artery.