Suboccipital triangle
Encyclopedia
The suboccipital triangle is a region of the neck
bounded by the following three muscles of the suboccipital group of muscles:
(Rectus capitus posterior minor is also in this region but does not form part of the triangle)
It is covered by a layer of dense fibro-fatty tissue, situated beneath the Semispinalis capitis
.
The floor is formed by the posterior occipito-atlantal membrane, and the posterior arch
of the atlas
.
In the deep groove on the upper surface of the posterior arch of the atlas are the vertebral artery
and the first cervical or suboccipital nerve
.
The vertebral artery is accessed here in order to conduct angiography of the circle of Willis
.
2)Dorsal ramus of nerve C1-suboccipital nerve
3)Suboccipital venous plexus
The purpose of these muscles is to provide fine motor function in movements of the head. The actions of trapezius, sternocleidomastoid and other larger muscles that move the head are refined by the relatively small suboccipital triangle muscles.
Neck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
bounded by the following three muscles of the suboccipital group of muscles:
- Rectus capitis posterior major - above and medially
- Obliquus capitis superior - above and laterally
- Obliquus capitis inferior - below and laterally
(Rectus capitus posterior minor is also in this region but does not form part of the triangle)
It is covered by a layer of dense fibro-fatty tissue, situated beneath the Semispinalis capitis
Semispinalis capitis
The Semispinalis capitis is situated at the upper and back part of the neck, deep to the Splenius, and medial to the Longissimus cervicis and capitis....
.
The floor is formed by the posterior occipito-atlantal membrane, and the posterior arch
Posterior arch
In a cervical vertebra, the posterior arch forms about two-fifths of the circumference of the ring: it ends behind in the posterior tubercle, which is the rudiment of a spinous process and gives origin to the Recti capitis posteriores minores....
of the atlas
Atlas (anatomy)
In anatomy, the atlas is the most superior cervical vertebra of the spine.It is named for the Atlas of Greek mythology, because it supports the globe of the head....
.
In the deep groove on the upper surface of the posterior arch of the atlas are the vertebral artery
Vertebral artery
The vertebral arteries are major arteries of the neck. They branch from the subclavian arteries and merge to form the single midline basilar artery in a complex called the vertebrobasilar system, which supplies blood to the posterior part of the circle of Willis and thus significant portions of the...
and the first cervical or suboccipital nerve
Suboccipital nerve
The first cervical nerve, the suboccipital nerve exits the spinal cord between the skull and the first cervical vertebra, the atlas.It supplies muscles around the suboccipital triangle including the rectus capitis posterior major, obliquus capitis superior, and obliquus capitis inferior. The...
.
The vertebral artery is accessed here in order to conduct angiography of the circle of Willis
Circle of Willis
The Circle of Willis is a circle of arteries that supply blood to the brain...
.
Contents of the suboccipital triangle
1)Third part of vertebral arteryVertebral artery
The vertebral arteries are major arteries of the neck. They branch from the subclavian arteries and merge to form the single midline basilar artery in a complex called the vertebrobasilar system, which supplies blood to the posterior part of the circle of Willis and thus significant portions of the...
2)Dorsal ramus of nerve C1-suboccipital nerve
Suboccipital nerve
The first cervical nerve, the suboccipital nerve exits the spinal cord between the skull and the first cervical vertebra, the atlas.It supplies muscles around the suboccipital triangle including the rectus capitis posterior major, obliquus capitis superior, and obliquus capitis inferior. The...
3)Suboccipital venous plexus
Suboccipital venous plexus
The Suboccipital Venous Plexus drains the back of the head.It communicates with the external vertebral venous plexuses. The external vertebral venous plexuses travel inferiorly from this suboccipital region to drain into the brachiocephalic vein...
The purpose of these muscles is to provide fine motor function in movements of the head. The actions of trapezius, sternocleidomastoid and other larger muscles that move the head are refined by the relatively small suboccipital triangle muscles.