Corpus3D

Lower limb

Tendon sheath of extensor digitorum longus and fibularis tertius

Vagina tendinum musculi extensoris digitorum longi et fibularis tertii

Origin
Arises proximal to the inferior extensor retinaculum on the anterolateral ankle
Insertion
Spans the ankle joint and splits across the 4 tendons of extensor digitorum longus and fibularis tertius to the mid-metatarsal level
Function
Provides common synovial lubrication and frictionless gliding for the long toe extensor tendons and fibularis tertius
Innervation
Branches from the deep fibular nerve
Movement & chain
Glides during toe extension and ankle dorsiflexion
Palpation
Palpable across the anterolateral aspect of the ankle and dorsal midfoot
Clinical
EDL tenosynovitis from uphill running and athletic overload
Segmental innervation
L5, S1 spinal roots
In clinical practice
Calf muscle stretching to reduce dorsiflexion strain, eccentric tendon training, and physical therapy
Region in the model
Lower limb

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