Flexor digitorum brevis

The flexor digitorum brevis (Latin: musculus flexor digitorum brevis) is a superficial plantar muscle situated in the middle of the sole right above the plantar aponeurosis and below the tendon of the flexor digitorum longus muscle. It belongs to the central compartment (middle group) of the plantar foot muscles.

Flexor digitorum brevis
OriginMedial process of calcaneal tuberosity, plantar aponeurosis
Insertion Middle phalanges of toes 2 - 5
ActionToe flexion at 2nd to 5th metatarsophalangeal and proximal interphalangeal joints
InnervationMedial plantar nerve (S1 - S2)
Blood supply Medial and lateral plantar arteries

Origin

The flexor digitorum brevis muscle originates from the medial process of the calcaneal tuberosity and the plantar aponeurosis.

Insertion

The tendons of the flexor digitorum brevis insert on the middle phalanges of the second to fifth toes.

Action

The flexor digitorum brevis muscle flexes toes at the second to fifth metatarsophalangeal and proximal interphalangeal joints.

Innervation

The flexor digitorum brevis is innervated by the medial plantar nerve (S1 - S2) - a terminal branch of the tibial nerve.

Blood supply

The flexor digitorum brevis muscle receieves arterial blood supply from the medial and lateral plantar arteries. Both are branches of the posterior tibial artery.