Anatomy of Spinal Cord Flashcards
How many segments in spinal cord?
31 segments with nerves protruding
Where does spinal cord terminate?
Conus medullaris (L1,L2), but bundle of nerves still continues going down as cauda equina
What spinal column to coccyx?
Filus terminale
Exiting nerve locations in thorasic vs cervical vertebrae?
Nerve is rostral to cervical vertebra
nerve is caudal to vertebra
Dorsal roots vs ventral roots
Dorsal roots carry sensory into CNS, ventral roots carry motor out of CNS
In vertebral column, gray vs white matter?
White matter on outside (send info up and down between levels on tracks), gray matter on inner part buterfly (has dorsal, ventral horns involved in sensory and motor processing) contain cell bodies,
What part of white matter is the track that passes info up and down?
Funiculi (ventral, lateral, and dorsal funiculus)
What info is carried by laminae I- IV
exteroroceptive
What info is carried by laminae V and VI?
proprioceptive
What info is carried by lamina VII?
Visceral motor neurons/autonomic ganglia
What info is carried by lamina VIII-X?
motor
Which spinal segments are the largest?
Cervical segments. Size of segments change depending on level and reflects function
What is contained in the intermediolateral (IML) cell column?
found in lateral horns of thoracic segments which contain PRE-GANGLIONIC SYMPATHETIC neurons
What is a ganglion?
Cluster of neurons that lie outside of CNS (i.e. cell bodies of sensory neurons reside in DRG)
dermatome
region of skin supplied by right and left dorsal roots of a spinal segment
Ascending vs descending tracts?
Descending = motor asscending = sensory
Dorsal column (ascending tract)
transmits mechanosensory info (gracile and cuneate fasiculs)
Spinocerebellar tract
transmits proprioception info
Spinothalamic tract (ascending tract)
transmits noiception, thermoreception
Where do primary sensory neurons have cell bodies?
DRG
Where do neurons containing sensory neurons in dorsal column medial lemniscal system synapse?
Enter spinal cord and ascend WITHOUT synapsing
What do the spinocerebellar tracts convey?
Dorsal tracts convey nonconscious proprioceptive info about IPSILATERAL lower limbs to cerebellum
Key feature of spinothalamic tract?
Pain and temperature info ascends contralaterally (while mechanosensory info ascends ipsilaterally)