Corpus3D

Lower limb

Deltoid ligament of the ankle (Medial collateral ligament complex)

Ligamentum collaterale mediale articulationis talocruralis (Ligamentum deltoideum)

Origin
Medial malleolus of the tibia
Insertion
Navicular tuberosity (tibionavicular), sustentaculum tali (tibiocalcaneal), and talus (anterior/posterior tibiotalar)
Function
Extremely strong triangular ligament resisting eversion/pronation forces, preventing valgus talar tilting, and maintaining medial longitudinal arch
Innervation
Tibial nerve (L4–S1)
Movement & chain
Tensioned during hindfoot eversion and external rotation
Palpation
Palpable inferior and anterior to medial malleolus tip
Clinical
Eversion sprain (often associated with medial malleolus avulsion or proximal fibular fracture - Pott's / Maisonneuve); progressive collapsing foot deformity (pes planovalgus).
Segmental innervation
L4–S1
In clinical practice
Eversion stress testing, medial arch orthotics, and tibialis posterior kinetic strengthening
Region in the model
Lower limb