Thursday, 4/21-Spinal Cord Morphology (Stephens)

Question 1

List the spinal cord segments for the following sensory dermatomes:
Shoulder: \_\_
Thumb: \_\_
Little finger, elbow: \_\_
Nipple: \_\_
Umbilicus: \_\_
Inguinal region: \_\_
Big toe: \_\_
Little toe: \_\_
Perianal region: \_\_

Answer 1

C4
C6
T1
T4
T10
L1
L5
S1
S5

Question 2

List the spinal cord segments for the following motor dermatomes:
Biceps brachii muscle: \_\_
Brachialis muscle: \_\_
Triceps brachii muscle: \_\_
Muscles of hand: \_\_
Quadriceps: \_\_
Gastrocnemius: \_\_

Answer 2

C5-6
C6-7
C6-8
C8-T1
L2-4
L5-S2

Question 3

Disruption of blood flow to the __ artery results in Central Cord Syndrome, an ischemia of the central region of the SC

Answer 3

Anterior spinal

Question 4

This artery may be compromised secondary to thoracolumbar fracture or surgical repair of a abdominal aortic aneurysm (AAA). It is the major supply to the inferior 2/3 of the SC.

Answer 4

Great anterior artery of Adamkiewicz

Question 5

Which segments of the SC are vulnerable to watershed infarction?

Answer 5

C2-3
T1-4
L1

Question 6

The net result of the __ pathway is an alteration in muscle tone and reflexes and maintenance of accurate proprioceptive output from the neuromuscular spindles

Answer 6

Gamma efferent

Question 7

Increased gamma motor neuron activity causes has what effect on muscle tone and its associated reflex?

Answer 7

Hypertonia and hyperreflexia

Question 8

Decreased gamma motor neuron activity has what kind of effect on muscle tone and its associated reflex?

Answer 8

Hypotonia and hyporeflexia

Question 9

This sensory nucleus is in the posterolateral tip of the dorsal horn at ALL SC levels, it is involved in the Pain/Temperature pathway and sends fibers to the LSTT:

Answer 9

Substantia Gelatinosa

Question 10

This sensory nucleus is located at the mid-portion of the dorsal horn, is associated with the pain/temperature pathway, and sends its fibers to the fasciculus proprius:

Answer 10

Nucleus proprius

Question 11

This sensory nucleus is only present at thoracolumbar regions, is involved in unconscious proprioceptive pathways, and sends its fibers to the Dorsal Spinocerebellar tract (DSCT):

Answer 11

Nucleus Dorsalis (Clarke’s column)

Question 12

This sensory nucleus is located in thoracolumbar regions and S2-4, is involved in visceral sensory integration and reflex centers, and sends its fibers to intermediolateral gray, ventral horn, and hypothalamus via the fasciculus proprius (RF)

Answer 12

Visceral afferent nucleus

Question 13

This motor nucleus is located in the medial part of the ventral horn at all levels and innervates axial musculature:

Answer 13

Medial Motor Cell Column (MMCC)

Question 14

This motor nucleus is located in the lateral part of the ventral horn in the regions of the cervical and lumbosacral enlargements and innervates the muscles of the extremities:

Answer 14

Lateral motor cell column (LMCC)

Question 15

This motor nucleus is located in the lateral horn from T1-L2 and sends preganglionic sympathetic fibers to visceral structures

Answer 15

Intermediolateral nucleus

Question 16

This motor nucleus is located in the lateral horn from S2-4 and sends preganglionic parasympathetic fibers to the bowel and bladder:

Answer 16

Sacral autonomic nucleus

Question 17

The conus medullaris is at the ___ interspace and represents the tapered caudal extent of the SC.

Answer 17

LV1-2