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Head of talus

The head of the talus is the rounded anterior portion of the talus that projects forward and articulates with the navicular bone and the calcaneus (via the anterior and middle subtalar facets). It plays a critical role in the talonavicular joint and transverse tarsal (Chopart) joint, contributing to hindfoot mobility and medial longitudinal arch support.

The head of the talus is covered largely by articular cartilage, with limited non-articular surfaces for ligament attachment. Because of its extensive cartilage coverage and reliance on intraosseous blood supply, it is vulnerable to osteochondral lesions, avascular necrosis, and traumatic injuries.

Joints

  • Talonavicular joint: Major articulation with navicular bone

  • Anterior/middle subtalar facets: Articulates with calcaneus (sustentaculum tali)

  • Transverse tarsal joint (Chopart): Functional joint including talonavicular articulation

Ligament Attachments

  • Spring ligament (plantar calcaneonavicular ligament): Supports the talar head from below

  • Talonavicular ligament: Connects dorsum of talar head to navicular

  • Deltoid ligament (tibionavicular part): Stabilizes talar head medially

  • Bifurcate ligament (calcaneonavicular part): Provides lateral support

Tendon and Muscle Relations

  • Medial: Tibialis posterior tendon inserts into navicular, supporting talar head

  • Inferior: Flexor hallucis longus tendon passes beneath (via sustentaculum tali)

  • Lateral: Peroneus longus and brevis tendons pass laterally but do not attach directly

  • Superior: Extensor tendons cross over dorsum of talonavicular region

Nerve Supply

  • Tibial nerve branches: Supply talonavicular and subtalar joints

  • Deep peroneal nerve: Contributes to anterior talonavicular innervation

  • Sural nerve branches: Minor articular input laterally

Arterial Supply

  • Dorsalis pedis artery: Supplies head and neck through artery of sinus tarsi

  • Posterior tibial artery: Via deltoid branch and artery of tarsal canal

  • Peroneal artery: Contributes small lateral branches

Venous Drainage

  • Drains into dorsalis pedis, posterior tibial, and peroneal veins

  • Venous plexus around talar head communicates with deep system

Function

  • Load transmission: Distributes forces between hindfoot and forefoot

  • Arch support: Critical in maintaining medial longitudinal arch via talonavicular joint

  • Mobility: Allows inversion, eversion, and rotation in transverse tarsal joint

  • Joint stability: Provides articulation for smooth hindfoot–midfoot transition

Clinical Significance

  • Osteochondral lesions: Common in talar head due to cartilage load-bearing role

  • Fractures: May occur in high-energy trauma, often with subtalar/talonavicular disruption

  • Degenerative changes: Talonavicular arthritis in flatfoot deformity or rheumatoid arthritis

  • Avascular necrosis: Risk due to limited vascular redundancy

  • Imaging role: MRI and CT essential for cartilage, fracture, and vascular assessment

MRI Appearance

  • T1-weighted images:

    • Normal marrow: intermediate to high signal, depending on fat content

    • Fractures: low-signal linear defects through talar head

    • Osteonecrosis: diffuse or focal low-signal zones

  • T2-weighted images:

    • Normal marrow: intermediate to high signal, depending on fat composition

    • Bone marrow edema: bright hyperintense signal

    • Osteochondral lesions: focal bright defect with surrounding marrow edema

  • STIR:

    • Normal marrow: dark

    • Pathology: hyperintense signal in edema, fracture, or necrosis

  • Proton Density Fat-Saturated (PD FS):

    • Normal: homogeneous low-to-intermediate signal

    • Pathology: bright signal clefts or defects, ideal for osteochondral lesion detection

  • T1 Fat-Sat Post-Contrast:

    • Normal: mild homogeneous enhancement

    • Osteonecrosis: non-enhancing necrotic zones with rim enhancement

    • Cartilage defects: enhancement of perilesional bone marrow and synovium

MRI Arthrogram Appearance

  • Contrast fills the talonavicular joint space

  • Osteochondral defects: contrast pools into focal defects of talar head

  • Helps distinguish stable fissures (no contrast entry) vs unstable lesions (contrast entry)

CT Appearance

Non-Contrast CT:

  • Excellent for cortical definition of talar head fractures

  • Osteochondral lesions: visible as subchondral lucencies or cortical irregularities

  • Arthritis: joint space narrowing, osteophytes, sclerosis

Post-Contrast CT (standard):

  • Rarely performed for talus specifically

  • May show associated soft tissue enhancement

CT Arthrogram Appearance

  • Contrast highlights the talonavicular and subtalar articular surfaces

  • Osteochondral lesions: contrast-filled defects in talar head

  • Useful when MRI is contraindicated, particularly for cartilage evaluation

CT VRT 3D image

Head of talus 3d

MRI image

Head of talus sag MRI cross sectional anatomy 3T MRI AI enhanced radiology image-img-00000-00000

CT image

Head of talus sagittal CT cross sectional anatomy radiology image-img-00000-00000