Superficial back muscles (OIANs)

what are the superficial back muscles?

1. trapezius

2. latissimus dorsi

3. levator scapula

4. rhomboids

What are the attachments for the Trapezius?

O:

• medial 1/3 of the superior nuchal line

• external occipital protuberance

• nuchal ligament

• spinous process of C7-T12

I:

• Lateral 1/3 of clavicle

• acromion

• spine of scapula

what are the actions of the trapezius?

1. Elevation of the scapula (superior part)

2. Depression of the scapula (inferior part)

3. Retraction of the scapula ( middle part, or all three)

4. Upward rotation of the scapula (superior and inferior togther)

What is the innervation of the trapezius?

spinal accessory nerves and C3-C4 spinal nerve!

what are the attachments of the latissimus dorsi?

1. spinous process C7-T12

2. thorcalumbar fascisia

3. illiac crest

4. inferior 3-4 ribs

5. floor of intertubular sulcus of humerus (“groove”)

what are the actions of the latissimus dorsi?

1. extension of shoulder

2. adduction of shoulder

3. internal rotation of shoulder

what is the innervation for the latissiumus dorsi?

thoracodoral nerve

what are the attachments for the levator scapula?

1. posterior tubercles of transverse processes of C1-C4

2. medial border of scapula superior root of spine

what are the actions of the levator scapula?

1. elevation of scapula

2. downward rotation of the glenoid cavity

what are the innervations of the levator scapula?

1. C3-C4 spinal nerves

2. Dorsal scapular nerve

what are attachments for the rhomboids (major & minor)?

1. lower end of nuchal ligament

2. spinous processes of C7-T5

3. medial border of scapula from the spine of the scapula to the inferior angle

what are the actions of the rhomboids?

1. retraction of the scapula

2. downward rotation of the glenoid cavity

3. fixes scapula to the thoracic wall

what is the innervation of the rhomoids?

dorsal scapular nerve