Lumbricals of the foot

Lumbrical muscle of the foot
Muscles of the sole of the right foot, viewed from below. Second layer. (Lumbricals visible at bottom.)
Details
Origin	Medial borders of long flexor tendons
Insertion	Proximal phalanges and extensor tendons of the 4 lateral toes
Artery	Medial and Lateral plantar arteries
Nerve	medial and lateral plantar nerves (S3)
Actions	Flexes metatarsophalangeal joints, extends interphalangeal joints
Identifiers
Latin	musculus lumbricalis pedis
Dorlands /Elsevier	m_22/12549758
TA	A04.7.02.069
FMA	37453
Anatomical terms of muscle []

The lumbricals are four small skeletal muscles, accessory to the tendons of the flexor digitorum longus and numbered from the medial side of the foot; they arise from these tendons, as far back as their angles of division, each springing from two tendons, except the first.So the first lumbricle is unipenate and second,third and fourth are bipenate.

The muscles end in tendons, which pass forward on the medial sides of the four lesser toes, and are inserted into the expansions of the tendons of the Extensor digitorum longus on the dorsal surfaces of the proximal phalanges. All four lumbricals insert into extensor hoods of the phalanges, thus creating extension at the inter-phalangeal (PIP and DIP) joints. However, as the tendons also pass inferior to the metatarsal phalangeal (MTP) joints it creates flexion at this joint.

Absence of one or more; doubling of the third or fourth even the fifth. Insertion partly or wholly into the first phalanges.

The most medial lumbrical is innervated by the medial plantar nerve while the remaining three lumbricals are supplied by the lateral plantar nerve.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)