Miller's Anatomy - Spine Flashcards
(22 cards)
Where does the vertebral artery travel?
The vertebral artery travels in the transverse foramina of C6 to C1 (not C7).
What is the normal diameter of the cervical spine canal?
The diameter of the cervical spine canal is normally 17 mm.
At what diameter does the cervical cord become compromised?
The cervical cord may become compromised when the diameter is reduced to less than 13 mm (relative stenosis).
Where are the narrowest pedicles located?
The narrowest pedicles are at T5.
What is the major stabilizer of the atlantoaxial joint?
The transverse ligament is the major stabilizer of the atlantoaxial joint.
What is the composition of the annulus fibrosus?
The annulus fibrosus is obliquely oriented and composed of type I collagen.
What is the central nucleus pulposus made of?
The central nucleus pulposus is made of type II collagen and is softer than the annulus.
Where does the numbered nerve exit in the cervical spine?
In the cervical spine, the numbered nerve exits at a level above the pedicle of the corresponding vertebral level (e.g., the C2 nerve exits at the level of vertebrae C1-C2).
How does the nerve root traverse in the lumbar spine?
In the lumbar spine, the nerve root traverses the respective disc space above the named vertebral body and exits the respective foramen under the pedicle.
What does central disc herniation impinge upon?
Central disc herniation impinges upon the traversing nerve root.
What does lateral disc herniation impinge upon?
Lateral disc herniation impinges on the exiting nerve root.
What is the L5 nerve root’s relationship to the anterior sacral ala?
The L5 nerve root is relatively fixed to the anterior sacral ala and can be damaged by sacral fractures and errant anteriorly placed iliosacral screws.
What syndrome can result from disruption of the inferior cervical ganglia?
Disruption of the inferior cervical ganglia can lead to Horner syndrome (ptosis, miosis [pupillary constriction], and anhidrosis).
What injury can occur with right-sided anterior cervical approaches?
Injury to the recurrent laryngeal nerve can occur with right-sided anterior cervical approaches; paralysis is identified by a hoarse, scratchy voice caused by unilateral vocal cord paralysis, visualized with direct laryngoscopy.
Where does the recurrent laryngeal nerve arise on the right?
The recurrent laryngeal nerve arises from the vagus at the level of the subclavian artery on the right.
Where does the recurrent laryngeal nerve arise on the left?
The left recurrent laryngeal nerve arises at the level of the aortic arch.
What is the most common complication with a posterior cervical approach?
Postoperative C5 palsy is the most common complication with a posterior cervical approach.
What can injury to the lumbar plexus cause?
Injury to the lumbar plexus, particularly the superior hypogastric plexus, can cause sexual dysfunction and retrograde ejaculation.
At what level do the great vessels bifurcate?
The great vessels bifurcate at the L4-L5 disc.
What is the safe zone for anterolateral halo pins?
The safe zone for anterolateral halo pins is approximately 1 cm superior to the orbital rim in the outer two thirds of the orbit below the equator of the skull.
What percentage of total neck flexion and extension occurs at the occiput-C1 articulation?
50%
What percentage of total neck rotation occurs at the C1-C2 articulation?
50%
