The Back Nerves and Vessels Flashcards
Where does the spinal cord lie?
Lies in vertebral canal (not intervertebral canal)
Where does the spinal cord end?
Ends as conus medullaris at L1 (adult); L3 (child)
What forms the cauda equina?
Lumbar, sacral nerves and the coccygeal nerve
Where does the pia extend and attach to?
coccyx as filum terminale
What is between the Arachnoid and the pia
subarachnoid space, filled with CSF
Where is the lumbar puncture?
Lumbar puncture at L3/4 or L4/5.
Where do the Dural and arachnoid extend to?
S3 vertebra = dural sac
The dural sac is the membranous sheath of dura mater that surrounds the spinal cord and the cauda equina. Contains CSF.
What are Cervical and Lumbar enlargements for?
(for brachial and lumbar, plexus nerves, resp.)
What does the lateral horn contain?
Cell bodies of the sympathetic neurons.
Where is the lateral horn present?
Between levels T1-L2/3 vertebrae (thoracolumbar/sympathetic outflow), and between levels S2-S4 vertebrae (sacral/parasympathetic outflow).
Do sympathetic nerves synapse before reaching the muscle/ tissue?
Yes
Is the grey ramus myelinated?
No
Is the white ramus myelinated?
Yes
What is the position of the paravertebral (sympathetic trunk) ganglia?
Lie parallel to the spinal cord
What is the travel of the sympathetic nerve impulses?
They emerge in the ventral root via a white ramus (preganglionic fibres). After synapsing in the sympathetic chain ganglion, they re-enter the spinal nerve via a grey ramus and are distributed in both dorsal and ventral rami of the spinal nerve (postganglionic fibres).