AnatoMemory

Muscle

Flexor digitorum longus

Flexes the lateral four toes

Lower limbMuscular system

High-yield

Flexes toes 2-5; tibial nerve. Its tendon runs behind the medial malleolus (Tom, Dick, and Harry).

Overview

A deep posterior leg muscle flexing the lateral four toes and plantarflexing the ankle; its tendon crosses that of tibialis posterior.

Reference facts

Origin
Posterior surface of the tibia (below the soleal line)
Insertion
Bases of the distal phalanges of the lateral four toes
Action
Flexes the lateral four toes and plantarflexes the ankle; supports the arches
Innervation
Tibial nerve (L5, S1, S2)
Blood supply
Posterior tibial artery

Frequently asked questions

What does the flexor digitorum longus do?

The flexor digitorum longus flexes the lateral four toes and plantarflexes the ankle; supports the arches.

What nerve innervates the flexor digitorum longus?

The flexor digitorum longus is innervated by the tibial nerve (L5, S1, S2).

Where does the flexor digitorum longus attach?

The flexor digitorum longus originates from the posterior surface of the tibia (below the soleal line) and inserts on the bases of the distal phalanges of the lateral four toes.

What is the blood supply of the flexor digitorum longus?

The flexor digitorum longus is supplied by the posterior tibial artery.