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Body of talus

The body of the talus is the largest part of the talus, forming the superior articular trochlea that articulates with the tibia and fibula to make up the ankle joint. Inferiorly, it articulates with the calcaneus at the posterior facet of the subtalar joint, and anteriorly, it narrows into the talar neck leading to the head. The body plays a crucial role in weight transmission, ankle stability, and subtalar motion.

The talar body is covered largely by articular cartilage and has a retrograde vascular supply, which makes it highly vulnerable to avascular necrosis (AVN) following fractures, especially at the talar neck.

Joints

  • Talocrural joint: Superior articulation with tibia and fibula via trochlea of talus

  • Subtalar joint: Inferior articulation with calcaneus (posterior facet)

  • Talonavicular joint (via neck and head): Functionally linked to talar body movement

Ligament Attachments

  • Lateral ligaments: Posterior talofibular ligament attaches to the lateral tubercle of the posterior process

  • Medial ligaments (deltoid): Deep posterior tibiotalar part attaches to the medial talar body

  • Talocalcaneal ligaments: Medial, lateral, and posterior talocalcaneal ligaments stabilize the subtalar articulation

Tendon and Muscle Relations

  • Posterior: Groove for flexor hallucis longus tendon passes between posteromedial and posterolateral tubercles

  • Lateral/medial: Surrounded by tendons crossing the ankle joint (tibialis posterior, flexor digitorum longus, peroneals), but no direct muscle attachments

Nerve Supply

  • Tibial nerve: Subtalar and talocrural joint innervation

  • Deep peroneal nerve: Talocrural joint

  • Sural and saphenous nerves: Contribute minor articular supply

Arterial Supply

  • Posterior tibial artery: Artery of tarsal canal and deltoid branch → supply talar body

  • Dorsalis pedis artery: Artery of tarsal sinus supplies neck and part of body

  • Peroneal artery: Lateral contributions

  • Clinical note: Retrograde blood flow makes talar body fractures prone to osteonecrosis

Venous Drainage

  • Venous plexuses drain into posterior tibial, dorsalis pedis, and peroneal veins

Function

  • Weight transmission: From tibia to hindfoot and forefoot

  • Joint stability: Central element of ankle and subtalar joints

  • Range of motion: Allows dorsiflexion, plantarflexion, inversion, and eversion

Clinical Significance

  • Fractures: Talar body fractures are serious, often intra-articular, and associated with AVN

  • Osteochondral lesions: Particularly at the talar dome (osteochondritis dissecans, OCD)

  • Osteoarthritis: Post-traumatic degeneration common at ankle and subtalar joints

  • Avascular necrosis: High risk due to fragile blood supply, especially after neck/body fractures

MRI Appearance

  • T1-weighted images:

    • Marrow signal is intermediate-to-high depending on fat content

    • Fracture lines: low-signal linear defects through talar body

    • AVN: diffuse or focal low signal intensity in talar dome/body

  • T2-weighted images:

    • Normal marrow: intermediate-to-high depending on fat fraction

    • Edema: bright hyperintense signal within talar body

    • Osteochondral lesion: hyperintense defect at dome with surrounding marrow changes

  • STIR:

    • Normal: suppressed low signal

    • Pathology: bright hyperintense edema in trauma, AVN, or osteochondral lesions

  • Proton Density Fat-Saturated (PD FS):

    • Normal: uniform low-intermediate signal

    • Pathology: fractures and cartilage defects appear as bright abnormal signal

    • Excellent for early detection of osteochondral lesions

  • T1 Fat-Sat Post-Contrast:

    • Normal: homogeneous, minimal enhancement

    • AVN: non-enhancing necrotic regions with peripheral rim enhancement

    • Inflammation/synovitis: diffuse enhancement around body

MRI Arthrogram Appearance

  • Contrast outlines ankle and subtalar articular surfaces

  • Osteochondral lesions: contrast enters subchondral defects at talar dome

  • Differentiates stable fissures (no contrast) from full-thickness cartilage loss

CT Appearance

Non-Contrast CT:

  • Provides excellent visualization of cortical fractures, subchondral sclerosis, or collapse

  • Detects subtle osteochondral lesions of the talar dome

  • AVN may present as areas of collapse and fragmentation

Post-Contrast CT (standard):

  • Rarely used for bone itself

  • May demonstrate surrounding soft tissue pathology

CT Arthrogram Appearance

  • Contrast fills joint surfaces around talar body

  • Osteochondral lesions: linear or focal contrast penetration into subchondral defects

  • Useful when MRI is contraindicated and for detailed cartilage evaluation

MRI image

Body of the Talus sag MRI cross sectional anatomy 3T MRI AI enhanced radiology image-img-00000-00000

CT image

Body of the Talus CT cross sectional anatomy radiology image-img-00000-00000