Topics

Topic

design image
Lateral talocalcaneal ligament

The lateral talocalcaneal ligament is a short but strong ligament in the lateral ankle that connects the lateral process of the talus to the lateral surface of the calcaneus. It is part of the subtalar joint capsule and functions as a stabilizer of the subtalar joint. Though less prominent than the calcaneofibular ligament (CFL), it runs nearly parallel to it and acts as a secondary stabilizer against inversion stress.

This ligament is clinically important in ankle sprains, subtalar instability, and chronic lateral ankle pain. It is less frequently injured than the anterior talofibular ligament (ATFL) and CFL but may be damaged in combined ankle and subtalar injuries.

Synonyms

  • Lateral calcaneotalar ligament

  • External talocalcaneal ligament

Origin, Course, and Insertion

  • Origin: Lateral process of the talus

  • Course: Runs almost horizontally, slightly downward and posterior, lying deep and parallel to the calcaneofibular ligament

  • Insertion: Lateral surface of the calcaneus, near the anterior border of the calcaneofibular ligament attachment

Relations

  • Superiorly: Peroneal tendons (fibularis longus and brevis)

  • Inferiorly: Lateral calcaneal surface and subtalar joint capsule

  • Anteriorly: Anterior talofibular ligament (ATFL)

  • Posteriorly: Calcaneofibular ligament (CFL) running in parallel

Function

  • Subtalar stability: Reinforces the subtalar joint capsule

  • Secondary stabilizer: Assists the calcaneofibular ligament in resisting inversion

  • Load sharing: Helps maintain alignment of the talus and calcaneus under weight bearing

  • Kinematics: Contributes to smooth subtalar motion during walking and running

Clinical Significance

  • Sprains: Rarely injured in isolation; usually damaged along with ATFL and CFL in lateral ankle sprains

  • Subtalar instability: Lateral talocalcaneal ligament injury can cause recurrent subtalar joint instability

  • Chronic lateral ankle pain: May be involved in complex ligamentous injuries, particularly in athletes

  • Imaging relevance: MRI essential for detecting subtle tears; often overlooked compared with CFL and ATFL injuries

  • Surgical importance: Recognition is vital in subtalar stabilization procedures

MRI Appearance

  • T1-weighted images:

    • Normal ligament: low signal (dark), thin band from talus to calcaneus

    • Surrounded by intermediate muscle and bright fat planes for contrast

    • Tear: focal discontinuity or irregular thickening with intermediate signal

  • T2-weighted images:

    • Normal ligament: dark linear band

    • Tear: bright hyperintense signal at ligament substance or attachment site

    • Subtalar effusion may highlight injury site

  • STIR:

    • Normal: uniformly dark

    • Pathology: bright signal intensity indicating edema, partial tear, or periligamentous inflammation

  • Proton Density Fat-Saturated (PD FS):

    • Normal: thin dark band

    • Injury: hyperintense signal clefts or thickening, best sequence for subtle sprain detection

    • Detects associated peroneal tendon sheath edema

  • T1 Fat-Sat Post-Contrast:

    • Normal ligament: minimal enhancement

    • Injury: enhancement at tear margins or surrounding capsule, indicating inflammation or scar tissue

CT Appearance

Non-Contrast CT:

  • Ligament itself poorly visualized

  • Subtle injuries may be inferred from periarticular calcification, avulsion fractures, or subtalar joint irregularity

Post-Contrast CT:

  • Ligament not directly outlined, but surrounding soft tissue enhancement may suggest inflammation

  • Useful mainly for ruling out associated fractures or bony abnormalities

MRI image

lateral talocalcaneal ligament sag cross sectional anatomy 3T MRI AI enhanced radiology image-img-00000-00000

MRI image

lateral talocalcaneal ligament sag cross sectional anatomy 3T MRI AI enhanced radiology image-img-00000-00000_00001