Unit 4 - Spine, Superficial, Intermediate, and Deep Back Muscles

Question 1

What nerve innervates the trapezius m? blood supply?

Answer 1

cranial nerve XI/ accessory nerve, C3-C4 for proprioception; transverse cervical vessels

Question 2

What motion does the trapezius muscle do?

Answer 2

upper fibers elevate the scapula
middle fibers adduct the scapula
lower fibers depress the scapula
also helps in rotation of scapula during abduction

Question 3

What nerve innervates the latissimus dorsi muscle? blood supply?

Answer 3

thoracodorsal nerve (C6-C8); thoracodorsal vessels and intercostal vessels

Question 4

What motion does the latissimus dorsi do?

Answer 4

extends, adducts, and medially rotates the humerus

also depresses the shoulder

Question 5

What innervates the levator scapulae muscle? blood supply?

Answer 5

dorsal scapular nerve (C4-C5); dorsal scapular vessels

Question 6

What motion does the levator scapulae muscle do?

Answer 6

elevates the scapula

Question 7

What nerve innervates the rhomboid minor and major muscles? blood supply?

Answer 7

dorsal scapular nerve (C4-C5); dorsal scapular vessels

Question 8

What motion does the rhomboid muscles do?

Answer 8

adduct and elevate the scapula

Question 9

What are the intermediate muscles of the back and what do they do?

Answer 9

serratus posterior superior -helps with inhalation

serratus posterior inferior- helps with exhalation

Question 10

What are the deep muscles of the back?

Answer 10

suboccipital muscles
splenius capitus
semispinalis capitus
iliocostalis
longisimus
spinalis

Question 11

What innervates splenius capitus?

Answer 11

posterior rami of the middle and inferior cervical nerves

Question 12

What does splenius capitus muscle do?

Answer 12

draws head back, extends neck (bilaterally)

rotates head ipsilaterally (individually)

Question 13

What does the semispinalis capitus m do?

Answer 13

bilaterally extends the vertebral column

individually rotates the head ipsilaterally

Question 14

What 3 muscles make up the suboccipital triangle?

Answer 14

rectus capitus posterior major
obliquus capitus superior
obliquus capitus inferior

Question 15

What nerve and artery supply the 4 muscles of the suboccipital region?

Answer 15

C1 and vertebral a.

Question 16

Where do you see C1 and the vertebral a in the suboccipital region?

Answer 16

coming directly through the middle of the triangle

Question 17

What innervates the erector spinae muscles? blood supply?

Answer 17

dorsal rami of spinal nerves; lumbar and intercostal vessels

Question 18

What do the erector spinae muscles do?

Answer 18

erect the spine and head

Question 19

What are the erector spinae muscles?

Answer 19

iliocostalis, longissimus, spinalis

Question 20

What innervates the multifidus muscle? blood supply?

Answer 20

dorsal rami of the spinal nerves; lumbar vessels

Question 21

What action does multifidus do?

Answer 21

flex and laterally rotate the spine (contralaterally)

Question 22

What innervates the rotatores muscle? blood supply?

Answer 22

dorsal rami of the spinal nerves; intercostal vessels

Question 23

What action does the rotatores muscle do?

Answer 23

rotates the spine contralaterally

bilaterally erect spine