Innervation and vasculature of the back and thorax

Question 1

How many pairs of thoracic spinal nerves supply the thoracic wall

Answer 1

12 pairs

Question 2

What forms the intercostal nerves

Answer 2

anterior rami of spinal nerves T1-T12

Question 3

What areas do the posterior rami of spinal nerves T1-t12 innervate

Answer 3

the joints, muscles, skin of the back of the thoracic region

Question 4

What are the dermatomes that correlate with the anterior thorax region

Answer 4

C5 and T1-T6

Question 5

What anterior dermatomes correlate with the upper limb and the thorax

Answer 5

C5 and T1

Question 6

What land mark corresponds with the C5 dermatome

Answer 6

jugular notch and clavicles

Question 7

What land mark corresponds with the T1 dermatome

Answer 7

inferior to C5 and continues down anterior of upper limb

Question 8

What land mark corresponds with the T4 dermatome

Answer 8

nipples

Question 9

What land mark corresponds with the T7 dermatome

Answer 9

xiphoid process

Question 10

What land mark corresponds with the T10 dermatome

Answer 10

umbilicus

Question 11

On the posterior what is the most superior dermatome that does not supply the upper limb

Answer 11

T1

Question 12

Where do the posterior intercostal arteries arise from, were do they travel, and what do they give rise to

Answer 12

• Arise from aorta and travel toward the anterior thorax

- gives rise to lateral cutaneous branch

Question 13

Where do the anterior intercostal arteries arise from and what do they give rise to

Answer 13

• Arise= subclavian -> internal thoracic artery-> anterior intercostal artery
• give rise to perforating cutaneous arteries of the anterior thorax

Question 14

True or False the posterior and anterior intercostal arteries anastomose

Answer 14

True

Question 15

Where do the anterior intercostal veins go

Answer 15

internal thoracic vein, they mirror the arterial flow

Question 16

Where do the posterior intercostal veins end

Answer 16

azygos/hemiazygos venous system

Question 17

True of false the anterior and posterior intercostal veins anastomose

Answer 17

True, just like the arteries

Question 18

Where do most superficial lymph vessels above the umbilicus drain

Answer 18

axillary lymph nodes

Question 19

Where do most superficial lymph vessels below the umbilicus drain

Answer 19

inguinal lymph nodes

Question 20

What word describes the sequence for the structures in the intercostal space

Answer 20

V=vein
A=artery
N=nerve