Lower limb

Flexor hallucis longus

Musculus flexor hallucis longus

Origin

Posterior surface of the fibula and the interosseous membrane

Insertion

Base of the distal phalanx of the great toe

Function

Flexion of the great toe, supports plantarflexion of the foot and is important during push-off

Innervation

Tibial nerve, predominantly S2-S3

Movement & chain

Crucial in the final phase of push-off during walking and running, where the great toe actively flexes to transmit force to the ground.

Palpation

The tendon can be followed behind the medial malleolus and under the sole to the great toe.

Clinical

'Dancer's tendinitis': inflammation of this muscle's tendon behind the medial malleolus, common in ballet dancers due to repeated relevé movements.

Segmental innervation

S2-S3, part of the myotome testing pattern for flexion of the great toe.

In clinical practice

Diabetic foot inspection and pressure ulcer prevention; monitor for friction points from footwear or bedding and ensure correct anti-embolism stocking fit.

Region in the model

Lower limb