Lecture 16: Suboccipital Triangle Joints Of Head And Neck Flashcards
This part of the atlas articulates with occipital condyles and with axis. A. Posterior tubercle B. Posterior arch C. Transverse process D. Lateral masses
Ans D Bony Articulations Occipital bone: Occipital condyles Atlas: •Posterior tubercle •Posterior arch •Anterior arch •Transverse process with foramina •Lateral masses: Articulation with occipital condyles and Articulation with axis
What is true of atlas?
A. 2nd vertebra
B. No body or centrum
C. Only posterior arches have midline tubercle
D. Posterior arch not equivalent to pedicle and laminae of typical vertebrae
Ans B
Bony articulation atlas
The lateral masses possess on their superior surfaces the articular surfaces for the occipital condyles on the occipital bone.
The transverse processes are similar to those on the other cervical vertebrae and have transverse foramina for the vertebral
arteries.
Both the anterior and posterior arches have midline tubercles.
Note, however, that the atlas lacks a body or centrum as well as a spinous process.
The posterior arch is equivalent to the pedicels & laminae of typical vertebrae.
Odontoid process is part of which vertebrae A. Atlas B. Axis C. Cervical vertebrae D. Sacram
Ans: B
Axis:
Dens (odontoid process)
Spinous process
Transverse processes w/ foramina
The axis is shown here in a superior perspective. It has all
the parts of a typical vertebra, as well as transverse foramina.
Note that the spinous process is short and bifid, meaning that it is notched. The superior articular surfaces articulate with the
inferior articular surfaces of the atlas.
The major specialization of the axis is a pointed projection
coming off the superior surface of the centrum. This is the dens or odontoid process
This ligament is segmented and extends along the roof of the vertebral canal running from lamina to lamina A. Ligamentum flavum B. Ligamentum nuchae C. Anterior longitudinal ligament D. Posterior longitudinal ligament
Ans A Ligaments of vertebral column: Anterior longitudinal ligament Posterior longitudinal ligament Ligamentum flavum Ligamentum nuchae: Supraspinous + interspinous ligaments
The ligaments of the vertebral column were discussed earlier but
are mentioned here in relation to the role they play in the
articulation of the vertebral column to the skull.
These two ligaments run along the posterior and anterior surfaces of the centra of the vertebral column.
The supraspinous ligament runs along vertebral spinous processes the entire length of the vertebral column.
The ligamentum flavum is segmented & extends along the roof of
vertebral canal, running from lamina to lamina.
What is true of of cervical and craniotomy vertebral joint?
A. 3 synovial joint with intervertebral disc
B. Between dens and lateral masses
C. Between lateral masses and anterior arch of atlas
D. Has 4 ligaments: apical, alar, cruciate and tectorial
Ans D
Cervical and Craniovertebral Joints
Three synovial joints:
No intervertebral disc.
Between dens and anterior arch of the atlas.
Between lateral masses of atlas and axis (x2).
Ligaments: Apical ligament. Alar ligaments. Cruciate ligaments. Tectorial membrane.
Posterior atlatooccipital membrane is the extension of A. Anterior longitudinal ligament B. Cruciform ligament C. membrane tectoria D. Ligamentum flavum
Ans: D
The anterior longitudinal ligament extends from the tubercle on the anterior arch of the atlas to the base of the skull just anterior to the anterior rim of the foramen magnum. This extension of the anterior longitudinal ligament forms the anterior AOM (anterior atlantooccipital membrane).
The posterior longitudinal ligament extends all the way in through the foramen and attaches to the posterior rim of the foramen magnum. This extension from the atlas is referred to as the membrane tectoria.
The ligamentum flavum segment that extends from the atlas to the anterior rim of the foramen magnum is the posterior atlantooccipital membrane (AOM).
Note that between the membrane tectoria and the tip of the dens, seen in cross-section, is another ligament, called the cruciform ligament. This ligament can be seen in a posterior view with the membrane tectoria removed in the smaller diagram.
Which muscle helps rotate the atlas? A. Obliquus capitis superior B. Obliquus capitis inferior C. Rectus capitis posterior major D. Rectus capitis posterior
Ans B
Suboccipital Triangle Muscles
Obliquus capitis superior: Weak extensor of the neck Obliquus capitis inferior: Strong rotator of atlas
Rectus capitis posterior major: Extension of vertebral column
Rectus capitis posterior minor:Extension of vertebral
Which muscle of the suboccipital triangle muscles attach to both axis and atlas? A. Obliquus capitis superior B. Obliquus capitis inferior C. Rectus capitis posterior major D. Rectus capitis posterior
Ans B
Obliquus capitis superior: Weak extensor of the neck (skull to C1 atlas)
Obliquus capitis inferior: Strong rotator of atlas (atlas to axis)
Rectus capitis posterior major: Extension of vertebral column (skull to axis)
Rectus capitis posterior minor: Extension of vertebral column
(skull to atlas )
Motor innervation of the suboccipital muscles is provided by: A. C1 anterior branch B. C1 dorsal ramus C. Dorsal rami of C2 D. Dorsal rami of C3
Ans B
Suboccipital Triangle Floor and Roof
Floor: Posterior atlanto-occipital membrane
Roof: Semispinalis capitis muscle
C1 dorsal ramus provides motor innervation to the suboccipital muscles. The dorsal rami of C2 and C3 provide sensory supply.
Contents of Suboccipital Triangle do not include: A. Suboccipital nerve B. Greater occipital nerve C. Jugular Vein D. Vertebral artery
Ans C
Suboccipital Triangle Contents
Suboccipital nerve: Dorsal ramus of C1 No sensory function and no dorsal root
Motor to muscles of suboccipital triangle
Greater occipital nerve: Dorsal ramus of C2 Sensory to back of skull
Third occipital nerve: Dorsal ramus of C3
Vertebral artery
Veterbral artery passes though transverse foramina : A. Only through of cervical 4 B. Only through of cervical 5 C. Only though of cervical 6 D. Only though of cervical 7
Ans C
Note that the vertebral artery passes through the transverse foramina of the first six cervical vertebrae. The seventh cervical vertebra has transverse foramina, but the vertebral arteries does not pass through them.
Note in the top picture that the vertebral artery after passing through the transverse foramen of the atlas (#3) makes a sharp bend and then pierces the posterior atlantooccipital membrane (#1) and then enters the cranial cavity.
