Spinal Accessory Nerve Flashcards
Is the spinal accessory nerve a motor, sensory or mixed nerve?
Motor nerve
What does the motor nerve of the spinal accessory nerve supply?
Trapezius and SCM
Where does the SCM and trapezius receive sensory information?
C2,3,4 off the cervical plexus
What are the 2 roots of the spinal accessory nerve
Spinal root
Cranial root
Where are the cell bodies of the spinal root of the spinal accessory nerve located?
Cell bodies are located in the spinal accessory nucleus
Where is the spinal accessory nucleus found?
part of lamina ix of rexed and in the ventral horn of spinal cord segments C1-5
where do rootlets of the spinal root of the spinal accessory nerve emerge from?
Rootlets emerge from the cord (laterally, between the dorsal and ventral rootlet fibers) and form the spinal root of the XI nerve
where does the spinal root of the spinal accessory nerve ascend through?
The vertebral canal, the foramen magnum and into the cranial vault where it join the cranial root
Where are the cell bodies of the cranial root of the spinal accessory nerve located?
cell bodies are in the nucleus ambiguus
Do the cranial root fibers join with the spinal root of the spinal accessory nerve?
Yes, fibers from the cranial root leave the brainstem and joins (parallels) the spinal root
what cranial nerve does the cranial root of the spinal accessory nerve join and where?
At the jugular foramen, the cranial root joins the vagus nerve and is distributed as part of the vagus nerve
are the spinal root of the XI nerve ipsilateral or contralateral corticospinal innervations?
Contralateral due to pyramidal decussations that occur earlier in the upper motor neurons
Which SCM and trapezius is paralyzed with a left XI nerve lesion?
Left SCM and Trapezius
