The intertransversarii are small
muscles placed between the
transverse processes 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 characteristi ...
.
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, 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 of the
spinal nerves.
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 geograp ...
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-coordinat ...
, and the last pair between the seventh cervical and first
thoracic vertebræ.
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. These are called the '' thoracic intertransversarii'' and are supplied by the
posterior rami of the
spinal nerves.
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 of the vertebra below.
The intertransversarii laterales are supplied by the
anterior rami, and the intertransversarii mediales by the
posterior rami 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.
See also
*
Iliocostalis
Iliocostalis muscle is the muscle immediately lateral to the longissimus that is the nearest to the furrow that separates the epaxial muscles from the hypaxial. It lies very deep to the fleshy portion of the serratus posterior muscle. It latera ...
*
Interspinales muscles
*
Levatores costarum muscles
*
Longissimus
The longissimus ( la, the longest one) is the muscle lateral to the semispinalis muscles. It is the longest subdivision of the erector spinae muscles that extends forward into the transverse processes of the posterior cervical vertebrae.
Structu ...
*
Spinalis
The spinalis is a portion of the erector spinae, a bundle of muscles and tendons, located nearest to the spine. It is divided into three parts: Spinalis dorsi, spinalis cervicis, and spinalis capitis.
Spinalis dorsi
Spinalis dorsi, the medial c ...
References
External links
*
{{DEFAULTSORT:Intertransversarii Muscle
Muscles of the torso