In human anatomy, plantar interossei muscles are three
muscles
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of musc ...
located between the
metatarsal bone
The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the me ...
s in the
foot
The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg mad ...
.
Structure
The three plantar interosseous muscles are
unipennate
Muscle architecture is the physical arrangement of muscle fibers at the macroscopic level that determines a muscle’s mechanical function. There are several different muscle architecture types including: parallel, pennate and hydrostats. Force pr ...
, 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.
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.
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.
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.
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.
Additional images
Image:Gray269.png, Bones of the right foot. Plantar surface.
File:Slide1ABBBA.JPG, Muscles of the sole of the foot.
See also
*
Interosseous muscles of the hand
**
Dorsal interossei of the hand
In human anatomy, the dorsal interossei (DI) are four muscles in the back of the hand that act to abduct (spread) the index, middle, and ring fingers away from hand's midline (ray of middle finger) and assist in flexion at the metacarpophalange ...
**
Palmar interossei
In human anatomy, the palmar or volar interossei (interossei volares in older literature) are three small, unipennate muscles in the hand that lie between the metacarpal bones and are attached to the index, ring, and little fingers. They are sm ...
*
Interosseous muscles of the foot
The interosseous muscles of the foot are muscles found near the metatarsal bones that help to control the toes. They are considered voluntary muscles.
They are generally divided into two sets:
* 4 Dorsal interossei - Abduct the digits away fro ...
**
Dorsal interossei of the foot
In human anatomy, the dorsal interossei of the foot are four muscles situated between the metatarsal bones.
Origin
The four interossei muscles are bipenniform muscles each originating by two heads from the proximal half of the sides of adjacen ...
References
External links
PTCentral
{{Authority control
Foot muscles
Muscles of the lower limb