Plantar interossei muscles

In human anatomy, plantar interossei muscles are three muscles located between the metatarsal bones in the foot.

Plantar interossei muscles
The interossei plantares. Left foot.
Details
Origin	Metatarsals, long plantar ligament
Insertion	Medial side of proximal phalanges of 3rd to 5th toe
Artery	Plantar artery, and dorsal metatarsal A
Nerve	Lateral plantar nerve
Actions	Adduct toes
Antagonist	Dorsal interossei of the foot
Identifiers
Latin	musculi interossei plantares
TA98	A04.7.02.071
TA2	2687
FMA	37458
Anatomical terms of muscle [edit on Wikidata]

Structure

The three plantar interosseous muscles are unipennate, as opposed to the bipennate structure of dorsal interosseous muscles, and originate on a single metatarsal bone. The three muscles originate on the medial aspect of metatarsals III-V. The muscles cross the metatarsophalangeal joint of toes III-V so the insertions correspond with the origin and there is no crossing between toes.^[1]

The muscles then continue distally along the foot and insert in the proximal phalanges III-V. The muscles cross the metatarsophalangeal joint of toes III-V so the insertions correspond with the origin and there is no crossing between toes.^[1]

Innervation

All three plantar interosseous muscles are innervated by the lateral plantar nerve. The lateral plantar nerve is a branch from the tibial nerve, which originally branches off the sciatic nerve from the sacral plexus.^[1]

Function

Since the intersseous muscles cross on the metatarsophalangeal joint, then they act on that specific joint and cause adduction of toes III, IV, and V.^[1]

Adduction itself is not of extreme importance to the toes, but these muscles work together with the dorsal interosseous muscles in flexion of the foot. They also work together to strengthen the metatarsal arch.^[2]

Additional images

• 
  Bones of the right foot. Plantar surface.
• 
  Muscles of the sole of the foot.

See also

• Interosseous muscles of the hand
  • Dorsal interossei of the hand
  • Palmar interossei
• Interosseous muscles of the foot
  • Dorsal interossei of the foot

This article uses anatomical terminology.