Superficial

Question 1

What back muscles are part of the superficial layer?

Answer 1

1.) Trapezius
2.) Latissimus Dorsi
3.) Levator scapulae
4.) Rhomboid major
5.) Rhomboid Minor

Question 2

What are the origins and insertions for these muscles?

Answer 2

1.) Traps
O: Superior Nuchal Line (medial 1/3)+
EOP+
Ligamentum nuchae+
SP C7-T12
I: Lateral 1/3 of clavicle+
acromion process+
Spine of scapula

2.) Latissimus Dorsi
O: SP T7-S5+
Posterior iliac crest+
Ribs 10-12+
Inferior angle of scapula
I: humerus ( floor of bicipital groove)

3.) Levator Scapula
O: TVP’s C1-C4 ( posterior tubercles of TVPs)
I: Vertebral border of scapula ( superior to the spine and including the superior angle)

4.) Rhomboid Major
O: SP C7-T1
I: vertebral border of scapula (including the root and above)

5.) Thomboid minor
O: SP T2-T5
I: Vertebral border of scapula (below the spine)

Question 3

What nerves innervate this layer of the back?

Answer 3

1.) accessory (trapezius)
2.) Thoracodorsal ( lats)
3.) Dorsal scapular ( levator scap, rhomboids)

Question 4

What 3 muscles are innervated by the dorsal scapular nerve?

Answer 4

1.) Levator scapulae
2.) Rhomboid major
3.) Rhomboid Minor

Question 5

Of these 5 muscles, what is the only muscle to insert onto the humerus?

Answer 5

Latissimus Dorsi inserts onto the floor of the bicipital grove