3.1- Spinal Cord Anatomy Review Flashcards
Lateral Horn - ___________
- only ________ segments
- contain cell bodies of _____
autonomic
only T1-L2 segments
contain cell bodies of preganglionic sympathetic neurons
Dorsal (Posterior) Horn - ______
- runs through _________
- contains __________
sensory
runs thoughout SC except C1
contains large fibers that block pain (gait theory)
Ventral (Anterior) Horn - ______
- cell bodies of ______
- present throughout SC but larger in __________
motor
cell bodies of large alpha motor neurons
present throughout the spinal cord, but larger in areas where there is a lot of motor innervation (C-spine, L-spine)
What are rexid numbers?
numbered areas of spinal gray matter
What are 4 facts about the cervical cord?
- large with slightly flattened shape
- large ventral horn due to lots of muscles in the UE to innervate
- dorsal horn is also large due to sensory input from UE
- no lateral horn
What are 2 facts about the thoracic cord?
- very small ventral and dorsal horn- little sensory or motor
- lateral horn is present
What is a fact about the gray matter in the lumbar cord?
large ventral and dorsal horn due to large motor and sensory (proprioception) input from LE
What are 2 facts about the sacral cord?
- very small due to few fibers
- generally size of SC is largely dependent on # of cell bodies (gray matter) entering at that level (fibers generally don’t take up much space)
What area of the SC has large ventral horn due to lots of muscles in the UE to innervate?
cervical
What area of the SC has no lateral horn?
cervical
What area of the SC has large ventral & dorsal horn due to large motor and sensory input from LE?
lumbar
What area of the SC has very small ventral and dorsal horn?
thoracic
What area of the SC is very small due to few fibers and generally size of SC is largely dependent on # of cell bodies (gray matter) entering at that level?
sacral
Efferent fibers are in the _____________ Tract.
Afferent fibers are in the __________ & _______ Tract.
Lateral Corticospinal Tract
Dorsal Column System & Lateral Spinothalamic Tract
Lateral Corticospinal Tract-
Upper motor neurons originate in the _____ and pass down to the ______ (where they cross). They then run down the SC ____ side as the Lateral Corticospinal Tract.
motor cortex
brainstem
opposite
Lateral Corticospinal Tract-
Upper motor neurons originate in the motor cortex & pass down to the brainstem where they cross. They run down SC on opposite side. They synapse in _____ at level of innervations and leave the SC as the _____.
ventral horn
Lower Motor Neuron (Alpha Motor Neuron)
Dorsal Column System-
Neuron #1 enters through the _______ and travels up _____ side of the SC before crossing in the ______.
dorsal root ganglion
same side
brainstem
Lateral Spinothalamic Tract-
Neuron #1 originates in ______, enter SC through the ______, cross at _____ and ascend in SC in Lateral Spinothalamic Tract.
receptors
dorsal root ganglion
point of entry
Lateral Spinothalamic Tract detects ____ and ____.
Dorsal Column System detects ____, ____, and _____.
pain and temp
touch, kinesthesia, and vibration
Often SC injury is due to the interruption of the blood supply.
What are the 2 arteries of the SC and what do they supply?
- Anterior Spinal Artery- anterior 2/3 of spinal cord
2. Posterior Spinal Artery- other 1/3 of SC
_______ - one artery formed by the branches of the 2 vertebral arteries and supplies ventral horn, lateral corticospinal tract, lateral spinothalamic tract, part of dorsal horn
anterior spinal artery
_______ - splits in 2 branches and supplies dorsal column, part of dorsal horn
posterior spinal artery
Cauda Equina-
- injury here results in ______
- injury at _____ may result in both upper and lower motor neuron findings
lower motor neuron lesion
T12 or L1
What is the cauda equina?
What is the filum terminale?
composed of dorsal and ventral roots (spinal nerves)
continuation of the pia past the cauda equine that thickens and attaches to the coccyx (anchors)
