Innervations/ Actions BACK MUSCLES

Question 1

Trapezius

Answer 1

N: Accessory nerve
A: elevates scapula and pulls it medially or downward

Question 2

Latissimus dorsi

Answer 2

N:thoracodorsal nerve
A: Extends and medially rotates the humerus and moves it closer to the midline

Question 3

Levator scapulae

Answer 3

N: Dorsal scapular nerve
A: ‘elevates the scapula” (stabilizes and rotates as well)

Question 4

Rhomboids

Answer 4

N: Dorsal scapular nerve
A: Stabile, retract, and rotate the scapula

Question 5

Serratus posterior superior

Answer 5

N: Intercostal nerves
A: elevates the ribs

Question 6

Serratus posterior inferior

Answer 6

N: Intercostal nerves
A:Depresses the ribs

Question 6

Splenius capitis/ cervicis

Answer 6

N: Dorsal rami
A: bilateral contraction produces extension of the head and neck and unilateral contraction produces flexion of the head to one side or the other

Question 7

Erector spinae

Answer 7

N: Dorsal rami of the spinal nerves
A: bilateral contraction extends the vertebral column and unilateral contraction produces lateral flexion

Question 8

Suboccipital triangle

Answer 8

N: suboccipital nerve
Artery: vertebral artery

Question 9

Rectus capitus posterior major

Answer 9

A: extension of the head and lateral rotation of the head toward the contracting muscle

Question 10

Rectus capitus posterior minor

Answer 10

A: extension of the head

Question 11

Obliquus capitis superior

Answer 11

extension of the head and lateral flexion of the head toward the contracting muscle

Question 12

Obliquus capitis inferior

Answer 12

rotation of the head to the same side as contracting muscle

Question 13

What muscles make up sub. Occipital triangle boundaries?

Answer 13

Roof:semispinalis capitis
Floor: posterior arch of c1
Medial: rectus capitis  posterior major
Lateral: obliquus capitis superior
Inferior: obliquus capitis inferior

Question 14

What are the superficial muscles of the back?

Answer 14

Trapezius, latissimus dorsi, rhomboid major, rhomboid minor, levator scapulae

Question 15

What are the intermediate muscles of the back?

Answer 15

serratus posterior inferior and serratus posterior superior

Question 16

What are the deep superficial muscles?

Answer 16

splenius capitis and splenius cervicis

Question 17

What are the deep intermediate muscles?

Answer 17

erector spinae

Question 18

What are the deep deep muscles

Answer 18

transversospinalis, intertransversarii, interspinales, levatorescostarum