Flexor digitorum longus

The flexor digitorum longus (Latin: musculus flexor digitorum longus) is a relatively thin fusiform-shaped muscle of the lower leg. It belongs to the deep group of the posterior leg compartment. The flexor digitorum longus is located on the medial aspect of the calf, and it stretches between the tibia and distal phalanges of the foot.

Flexor digitorum longus
OriginPosterior surface of tibia below soleal line
InsertionBases of distal phalanges of toes 2-5
ActionFlexion of toes at 2nd - 5th metatarsophalangeal and interphalangeal joints, foot plantarflexion
InnervationTibial nerve (L5 - S2)
Blood supply Branches of posterior tibial artery

Origin

The flexor digitorum longus muscle originates from the posterior surface of the tibia below the soleal line.

Insertion

The flexor digitorum longus inserts on the bases of the distal phalanges of the second to fifth toes.

Action

The flexor digitorum longus muscle provides flexion of the toes at the second to fifth metatarsophalangeal and interphalangeal joints and aids in foot plantarflexion at the talocrural (ankle) joint.

Innervation

The flexor digitorum longus is innervated by the tibial nerve (L5 - S2) - a branch of the sciatic nerve.

Blood supply

The flexor digitorum longus muscle receieves arterial blood supply from the branches of the posterior tibial artery.