Muscles of the Back : Superficial and Intermediate layers

Question 1

what 4 superficial muscles in the back connect the upper limb to the trunk?

Answer 1

traps
lat dorsi
lev scap
rhomboid (+/-)

Question 2

Name the muscles in the intermediate layer of the back. hint: there are only 2

Answer 2

serratus posterior superior

serratus posterior inferior

Question 3

What are the attachment sites for the upper trap? what actions are avaliable to this muscle?

Answer 3

middle 1/3 of superior nuchal line, inion to the C7 SP to lateral clavicle, acromion

Actions:
(with head fixed) = S-T elevation /upward rotation

(with shoulder fixed) = Head/neck extension, ipsi lat flex, contra rot

Question 4

What are the attachment sites for the middle traps? what actions are avaliable to this muscle?

Answer 4

C7-T5 SP To superior lip of the spine of the scap

actions : S-T retraction

Question 5

What are the attachment sites for the lower traps? What actions are avaliable to this muscle?

Answer 5

T6- T12 SP to medial end of the spine of the scapula (root)

Actions: S-T Depression , upward rotation

Question 6

What are the attachment sites for Latissimus Dorsi and what are the avaliable range of motion.

Answer 6

SP T6- iliac crest, lumbar and sacral vertebrae via the thoracorlumbar fascia, ribs 9-12, inferior angle of scap ( sometimes) to floor of the bicipital groove

actions: G-H internal rot, extension, adduction

Question 7

What are the attachment sites for rhomoids and what are the avaliable range of motions?

Answer 7

SP C7-T5 to root of the spine of scap to the inf angle of scap

S-T retraction, downward rot, elevation
helps serratus ant to hold the scapula against the ribs

Question 8

What are the attachment sites for Levator scapula and what are the avaliable range of motions?

Answer 8

TVP of C1-4 to superior angle of the root of the spine of the scapula

S-T elevation, downward rotation
H/N extension, ipsi lat flex, ipsi lat rot

Question 9

What muscles fall in the intermediate layer of the back?

Answer 9

Serratus posterior superior

Serratus Posterior inferior

Question 10

The serratus posterior superior is deep to what muscle in the superficial layer? and superficial to what muscle in the deep layer of the back?

Answer 10

rhomboids

erector spinae

Question 11

What are the attachments of the serratus posterior superior and what are the avaliable actions?

Answer 11

SP C7-T3 to superior borders of the ribs 2-5

elevates ribs 2-5 during breath

Question 12

What muscle in the superficial layer is the serratus posterior inferior deep to and what muscle in the deep layer is it superior to?

Answer 12

latissimus and thoracolumbar fascia

erector spinae

Question 13

What are the attachments for the serratus posterior inferior and what are the avaliable actions?

Answer 13

SPs of T11- L2 to lower 4 ribs

draws ribs down and back during breathing