Shoulder Complex (2B)

Question 1

Attachments of pectoralis major

Answer 1

• proximal = medial clavicle (clavicular head), sternum, upper ribs (sternal head)
• distal = anterior/medial humerus

Question 2

Innervation of pectoralis major

Answer 2

Lateral and medial pectoral nerves

Question 3

Actions of pectoralis major

Answer 3

All fibers
- adduct the shoulder
- internally (medially) rotate the shoulder
- assist to elevate the thorax during forced inhalation (with the arm fixed)
Clavicular fibers
- flex the shoulder
- horizontally adduct the shoulder
Sternocostal fibers
- extend the shoulder

Question 4

Attachments of pectoralis minor

Answer 4

• proximal = 3-5th ribs (middle ribs)
• distal = coracoid process
• can move either attachment

Question 5

Innervation of pectoralis minor

Answer 5

Medial pectoral nerve

Question 6

Actions of pectoralis minor

Answer 6

• depression the scapula
• abduction the scapula
• downwardly rotate the scapula
• assist to elevate the thorax during force inhalation (with the scapula fixed)

Question 7

Attachments of coracobrachialis

Answer 7

• proximal = coracoid process
• distal = anterior/medial humerus

Question 8

Innervation of coracobrachialis

Answer 8

Musculocutaneous nerve

Question 9

Actions of coracobrachialis

Answer 9

• flex the shoulder
• adduct the shoulder

Question 10

Attachments of deltoid

Answer 10

• proximal = lateral clavicle, acromion, lateral spine of the scapula
• distal = lateral humerus

Question 11

Innervation of deltoid

Answer 11

Axillary nerve

Question 12

Actions of deltoid

Answer 12

All fibers
- abduct the shoulder
Anterior fibers
- flex the shoulder
- internally (medially) rotate the shoulder
- horizontally adduct the shoulder
Posterior fibers
- extend the shoulder
- externally (laterally) rotate the shoulder
- horizontally abduct the shoulder

Question 13

Muscles of rotator cuff

Answer 13

• SITS
• supraspinatus
• infraspinatus
• teres minor
• subscapularus

Question 14

Attachments of supraspinatus

Answer 14

• proximal = supraspinous fossa
• distal = lateral humerus

Question 15

Innervation of supraspinatus

Answer 15

Suprascapular nerve

Question 16

Actions of supraspinatus

Answer 16

• abduct the shoulder
• stabilize the head of humerus in glenoid cavity

Question 17

Attachments of infraspinatus

Answer 17

• proximal = infraspinous fossa
• distal = posterior/lateral humerus

Question 18

Innervation of infraspinatus

Answer 18

Suprascapular nerve

Question 19

Actions of infraspinatus

Answer 19

• externally (laterally) rotate the shoulder
• adduct the shoulder
• stabilize the head of humerus in glenoid cavity

Question 20

Attachments of teres minor

Answer 20

• proximal = lateral border of scapula
• distal = posterior/lateral humerus

Question 21

Innervation of teres minor

Answer 21

Axillary nerve

Question 22

Actions of teres minor

Answer 22

• externally (laterally) rotate the shoulder
• adduct the shoulder
• stabilize the head of humerus in glenoid cavity

Question 23

Attachments of subscapularis

Answer 23

• proximal = subscapular fossa
• distal = anterior/lateral humerus

Question 24

Innervation of subscapularis

Answer 24

Upper and lower subscapular nerve

Question 25

Actions of subscapularis

Answer 25

- internally (medially) rotate the shoulder - stabilize the head of humerus in glenoid cavity

Question 26

Attachments of teres major

Answer 26

- proximal = lower 1/3 of lateral border of scapula - distal = anterior/medial humerus

Question 27

Innervation of teres major

Answer 27

Lower subscapular nerve

Question 28

Actions of teres major

Answer 28

- extend the shoulder - adduct the shoulder - internally (medially) rotate the shoulder

Question 29

Attachments of latissimus dorsi

Answer 29

- proximal = inferior angle of scapula, spinous processes of inferior T-spine, and thoracolumbar fascia/posterior iliac crest - distal = anterior/medial humerus

Question 30

Innervation of latissimus dorsi

Answer 30

Thoracodorsal nerve

Question 31

Actions of latissimus dorsi

Answer 31

- extend the shoulder - adduct the shoulder - internally (medially) rotate the shoulder

Question 32

Attachments of trapezius

Answer 32

- proximal = occiput of scull, ligamentum nuchae, and C7-T12 spinous processes - distal = lateral 1/3 clavicle, spine of scapula, and acromion

Question 33

Innervation of trapezius

Answer 33

Cranial nerve (XI - Accessory)

Question 34

Actions of trapezius

Answer 34

Upper fibers - extend the head and neck Upper fibers (unilaterally) - laterally flex the head and neck to the same side - rotate the head and neck to the opposite side - elevate the scapula - upwardly rotate the scapula Middle fibers - adduct scapula - stabilize scapula Lower fibers - depression scapula - upwardly rotate the scapula

Question 35

Attachments of levator scapula

Answer 35

- proximal = transverse processes of C1-4 - distal = medial border of scapula

Question 36

Innervation of levator scapula

Answer 36

Dorsal scapular nerve

Question 37

Actions of levator scapula

Answer 37

Unilaterally - elevate the scapula - downwardly rotate the scapula - laterally flex the head and the neck - rotate the head and neck to the same side Bilaterally - extend the head and neck

Question 38

Attachments of rhomboid major and minor

Answer 38

- proximal = spinous processes of C7-T5 - distal = medial border of scapula

Question 39

Innervation of rhomboid major and minor

Answer 39

Dorsal scapular nerve

Question 40

Actions of rhomboid major and minor

Answer 40

- adduct the scapula - elevate the scapula - downwardly rotate the scapula

Question 41

Attachments of serratus anterior

Answer 41

- proximal = upper ribs - distal = medial border of scapula

Question 42

Innervation of serratus anterior

Answer 42

Long thoracic nerve

Question 43

Actions of serratus anterior

Answer 43

With the origin fixed - abduct the scapula - upwardly rotate the scapula - depression the scapula - hold the medial border of the scapula against the rib cage With the scapula fixed - may act to elevate the thorax during forced inhalation