The intertransversarii are small

muscle 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 muscl ...

s placed between the

transverse processes The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...

of the

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...

Structure

Cervical

In the cervical region they are best developed, consisting of rounded muscular and tendinous

fasciculi Fascicle or ''fasciculus'' may refer to: Anatomy and histology * Muscle fascicle, a bundle of skeletal muscle fibers * Nerve fascicle, a bundle of axons (nerve fibers) ** Superior longitudinal fasciculus *** Arcuate fasciculus ** Gracile fas ...

, and are placed in pairs, passing between the anterior and the posterior

tubercle In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection ...

s respectively of the transverse processes of two contiguous vertebrae, and separated from one another by an anterior primary division of the

cervical nerve A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the ...

, which lies in the groove between them. * The muscles connecting the anterior tubercles are termed the ''anterior intertransversarii''. * Those between the posterior tubercles are termed the ''posterior intertransversarii''. Both sets are supplied by the

anterior rami The ventral ramus (pl. ''rami'') (Latin for ''branch'') is the anterior division of a spinal nerve. The ventral rami supply the antero-lateral parts of the trunk (anatomy), trunk and the limbs. They are mainly larger than the dorsal ramus of spinal ...

of the

spinal nerve A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into th ...

s. There are seven pairs of these muscles, the first pair being between the

atlas An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geographic ...

and

axis An axis (plural ''axes'') is an imaginary line around which an object rotates or is symmetrical. Axis may also refer to: Mathematics * Axis of rotation: see rotation around a fixed axis *Axis (mathematics), a designator for a Cartesian-coordinate ...

, and the last pair between the seventh cervical and first

thoracic vertebræ In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervical ...

Thoracic

In the thoracic region they are present between the transverse processes of the lower three thoracic vertebrae, and between the transverse processes of the last thoracic and the first

lumbar In tetrapod anatomy, lumbar is an adjective that means ''of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum.'' The lumbar region is sometimes referred to as the lower spine, or as an area of the back i ...

. These are called the '' thoracic intertransversarii'' and are supplied by the

posterior rami The dorsal ramus of spinal nerve (or posterior ramus of spinal nerve, or posterior primary division) is the posterior division of a spinal nerve. The dorsal ramus (Latin for branch, plural ''rami'' ) is the dorsal branch of a spinal nerve that form ...

of the

Lumbar

In the lumbar region they are arranged in pairs, on either side of the vertebral column, * one set occupying the entire interspace between the transverse processes of the lumbar vertebrae, are the ''lateral lumbar intertransversarii''. * the other set, the ''medial lumbar intertransversarii'', passing from the accessory process of one vertebra to the

mammillary The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...

of the vertebra below. The intertransversarii laterales are supplied by the

, and the intertransversarii mediales by the

of the spinal nerves.

Function

They contribute little to no movement on their own, but they stabilize adjoining vertebrae allowing more effective action from other muscle groups.

References

External links

* {{DEFAULTSORT:Intertransversarii Muscle Muscles of the torso

Structure

Cervical

Thoracic

Lumbar

Function

See also

References

External links