Inferior Transverse Tibiofibular Ligament

ligamentum tibiofibulare transversum inferius

The inferior transverse ligament is the deep component of the posterior inferior tibiofibular ligament, running horizontally from the posterior fibula to the posterior tibial malleolus and projecting as a labrum-like structure deepening the posterior ankle mortise. It forms the posterior labrum of the ankle socket.

Region: Lower Leg

Biomechanics

Function & Actions

Deepens the posterior ankle socket, increasing talar dome congruence, and functions as the posterior restraint of the syndesmosis.

Clinical Relevance

Clinical Notes

The inferior transverse ligament is seen on coronal MRI as a fibular labrum at the posterior ankle joint. Its avulsion with bone produces a posterior malleolus fracture. In posterior ankle arthroscopy, this structure is visible as the fibrocartilaginous posterior ankle labrum. It may be torn in high ankle sprains and requires assessment when posterior ankle instability is present.

Pathology

Common Injuries & Conditions

Posterior Labral Tear of the Ankle

Disruption of the inferior transverse ligament functioning as the posterior ankle labrum, producing posterior ankle pain and instability in forced dorsiflexion, requiring posterior ankle arthroscopy for assessment.