Lecture 10/7: Spinal Arterial Circulation

Question 1

How many arteries run longwise on the spine? What are they called?

Answer 1

3 total

2 posterior spine A

1 anterior spine A

Question 2

What do the posterior spinal artieries feed into?

Answer 2

Vertebral arteries
Arterior inferior cerebellar arteries
posterior inferior cerebellar arteries

Question 3

Where are the posterior arteries located?

Answer 3

L/R sides of the posterior sulcus

Question 4

How much blood flow to the cord are the posterior spinal arteries reposible for?

Answer 4

25%

12.5% each

Question 5

Compare the anterior median fissure to the posterior median sulcus

Answer 5

Anterior median fissure is much larger/wider and able to hold a larger artery

Question 6

How much blood flow to the cord is the anterior artery reposible for?

Answer 6

75%

Question 7

What artery feeds into the anterior and posterior spinal arteries?

Answer 7

Radicular arteries

Question 8

Where does radicular arteries get blood from?

Answer 8

Intercostal arteries

Question 9

What are the interchangeable names for radicular arteries?

Answer 9

Segmental Arteries
Medullary Arteries
Radicular Arteries

Question 10

What are the Coronal Arteries?

Answer 10

“Crown” = Coronal

On the outer surface of the cord, similar to collateral circulation but NOT LIKE CIRCLE OF WILLIS not not accommodate for blockage

Question 11

How many anterior radicular Arteries do you have in the C-spine?

Answer 11

2

Question 12

How many anterior radicular Arteries do you have in the T-spine?

Answer 12

2-3

Question 13

How many anterior radicular Arteries do you have in the L-spine?

Answer 13

1-2

Question 14

T/F: You will have at least 1 radicular artery at level level of the spine

Answer 14

F

They are irregular
You will have 1 on the L or R or Front or Back every few levels and it varies per person

Question 15

Where there are arteries there are likely________

Answer 15

veins

Question 16

How many spinal veins do we have longwise?

Answer 16

4

3 posterior (1 is midline)

1 anterior

Question 17

You have a ________ at every level of the spine

Answer 17

Spinal branch

Question 18

Describe the spinal branch

Answer 18

They are at every level in the spine but they branch off in different way around the ribs

Question 19

Where is the spinal branch?

Answer 19

Sits on top of the dorsal root ganglia

Question 20

What feeds all the spinal arteries associated with the ribcage?

Answer 20

Thoracic Aorta

Question 21

What do the Mesenteric Arteries supply blood to?

Answer 21

Small intestines

Question 22

What are the 2 parts of the aorta?

Answer 22

Thoracic aorta
Abdominal aorta

Question 23

What do the intercostal arteries do?

Answer 23

Keeps ribcage healthy & perfused

Question 24

Where do you clamp when you have an aortic aneurysm?

Answer 24

Right above it

Question 25

What is the source of blood for ALL the radicular arteries?

Answer 25

Aorta

Question 26

What happens you clamp the cord to repair an aneurysm?

Answer 26

Cuts off circulation to the radicular arteries in spine Can lead to death of neurons in the cord

Question 27

What artery supplies a majority of blood to the cord?

Answer 27

Great radicular artery

Question 28

What is another name for the Great radiculary artery?

Answer 28

Artery of adamkiewicz GRA

Question 29

How much blood does the Great radicular artery supply to the cord?

Answer 29

Supplies blood to 2/3 of the lower cord

Question 30

What side of the cord is the Artery of adamkiewicz?

Answer 30

L side

Question 31

Where can the Great radicular artery be?

Answer 31

On L side of the cord at: T10 T9-T12 --------- 75% of the time T5-L5 ----------- Absolute range

Question 32

What happens if you have to clamp the cord above the Great radicular artery?

Answer 32

Lower part of spine is going unperfused === paralysis **If you have time to do imaging to find out where the GRA is please do**

Question 33

The _______ your GRA is, the safer it is if you need to clamp it.

Answer 33

higher up

Question 34

Equation for perfusion pressure?

Answer 34

PP = MAP - ICP

Question 35

What should ICP be?

Answer 35

10 mmHg

Question 36

What are ways to reduce cell death in the cord when clamped?

Answer 36

Reduce inflammation Reduce metabolic rate **These help slow down ischemia**

Question 37

What effect does aortic cross clamping have on CSF?

Answer 37

It increases CSF pressure on the cord by 10 mmHg **drains can help with this**

Question 38

What does the spinocerebellar tracts do?

Answer 38

coordinate complicated movements

Question 39

What does the posterior dorsal spinocerebellar tract do?

Answer 39

Gives info about tendons and muscle spindles

Question 40

What does the anterior ventral spinocerebellar tract do?

Answer 40

Tells how much motor activity is happening in the ventral horn

Question 41

Describe the Anterior ventral spinocerebellar tract pathway

Answer 41

1. Info comes from the ventral horn to the anterior ventral spinocerebellar tract 2. Info ascends to Superior cerebellar peduncle 3. From there info goes to the superior part of the cerebellum

Question 42

Describe the Posterior dorsal spinocerebellar tract pathway

Answer 42

1. Info comes from the dorsal horn to the Posterior dorsal spinocerebellar tract 2. Info ascends to inferior cerebellar peduncle 3. From there info goes to the inferior part of the cerebellum

Question 43

What is a tract?

Answer 43

Bundle of axons

Question 44

T/F: Ischemia doesn't cause pain

Answer 44

F

Question 45

Describe Parietal pain

Answer 45

Superficial tissue pain direct conduction into spinal cord Highly localized

Question 46

Describe visceral pain

Answer 46

Organ pain Autonomic nerves Referred pain (hard to pinpoint or think its somewhere else)

Question 47

T/F: Organs have tactile sensors

Answer 47

F They dont

Question 48

If the pain is close it's ______; if it's far it's __________

Answer 48

Parietal Visceral

Question 49

Where is parietal pain on organs?

Answer 49

Superficial parts

Question 50

Since the soft tissue in lungs and the liver doesn't have pain sensors, what type of pain do you feel from it?

Answer 50

Visceral pain

Question 51

T/F: Pain is related to membrane potential

Answer 51

T

Question 52

Where is heart pain felt?

Answer 52

L shoulder/arm

Question 53

What gives synaptic activity in the anterior horn?

Answer 53

Superior cerebellar peduncle

Question 54

Describe Appendix pain

Answer 54

Dual pain from surrounding tissue: sharp & stabbing **Visceral and parietal pain**

Question 55

Where is appendix pain felt?

Answer 55

Parietal pain: Lower R quadrant **You can apply pressure here** Visceral pain: T10 at umbilicus

Question 56

Why cant you apply pressure with visceral pain?

Answer 56

There are no tactile sensors

Question 57

Where is kidney pain felt?

Answer 57

Lower back

Question 58

Where is stomach pain felt? What can it be mistaken for?

Answer 58

High umbilicus Heartburn can be mistaken for a MI

Question 59

Where is the limbic system mostly?

Answer 59

Deep brain structres on top of brainstem

Question 60

What is the limbic system?

Answer 60

Emotional center of brain

Question 61

What are the 3 areas of the limbic system?

Answer 61

Hypothalamus Cingulate gyrus Amygdala

Question 62

Where is the Cingulate gyrus?

Answer 62

Superior to corpus callosum Buried in the middle of the brain **part of the cerebral cortex**

Question 63

What fibers are part of lateral inhibition?

Answer 63

A-beta fibers

Question 64

What fibers do slow pain use?

Answer 64

C-fibers

Question 65

What utilizes C-fibers?

Answer 65

Slow pain touch/pressure tickle aching pain cold warmth

Question 66

What fibers do fast pain use?

Answer 66

A-Delta fibers

Question 67

What fibers do skeletal muscle use?

Answer 67

A-alpha & beta fibers

Question 68

What fibers do tendons use?

Answer 68

A-alpha & beta fibers

Question 69

What fibers do muscle spindles use?

Answer 69

A-alpha, beta, gamma fibers