Cross-Sectional Anatomy of the Spinal Cord Flashcards
The Ventral (anterior) median fissure separates what?
It separates the ventral funiculi (white matter tract regions)
The Dorsal (posterior) median sulcus divides what?
It divides dorsal funiculi (white matter tract regions)
What does gray matter consist of?
Soma, unmyelinated processes and neuroglia
What does Gray commissure connect?
The Gray commissure connects R/L massesof gray matter
& encloses central canal
Dorsal horns within Gray Matter columns consist of:
Interneurons
(therefore a sensory synapse will occure here)
Ventral horns within Gray Matter Columns consist of:
Somatic (voluntary) motor neurons & some interneurons
Lateral horns within Gray Matter Columns contain:
Sympathetic motor fibers
& this column is present in T1-L2 only
Spinal Roots consist of:
Dorsal half
&
Ventral Half
Describe the Dorsal half of the Spinal Root
dorsal root ganglion (sensory nerve cell bodies) lead to dorsal roots
which expand into rootlets before entering the spinal cord
Where do the dorsal rootlets synapse?
May synapse at a dorsal horn interneuron or continue via axons
in the white matter columns towards the brain
Describe the Ventral half of the Spinal Roots
Motor rootlets join to form motor roots
How do dorsal and ventral roots fuse?
Dorsal and ventral roots fuse laterally to form short spinal nerves
Describe Gray Matter Somatotopy
Body representations in four zones (maintain spatial relationships)
What are the two visceral representations on the internal aspect?
visceral sensory (VS)
&
visceral motor (VM)
What are the two somatic representations on the external aspect?
somatic sensory (SS)
&
somatic motor (SM)
Describe White Matter Columns
- White matter columns are fibers that run in three directions - ascending, descending, and transversely
- Divided into three columns (funiculi) -dorsal, ventral, lateral
- Each white matter column contains several fiber tracts
What are the three directions that fibers run within White Matter Columns?
ascending
descending
transversely
What are the three columns (funiculi) that White Matter Columns are divided into?
dorsal
ventral
lateral
What doe the fiber tracts within White Matter Columns reveal?
Fiber tract names reveal their origin and destination
What are fiber tracts within White Matter Columns composed of?
Fiber tracts are composed of bundled axons with similar sensory functions
