5/20 - 5/21: Axilla and Brachial Plexus

Question 1

What is the insertion of the pectoralis major?

Answer 1

Humerus (crest of greater tuberosity)

Question 2

What is the innervation of the pectoralis major?

Answer 2

Medial and lateral pectoral n. (C5-T1)

Question 3

What is the action of the pectoralis major?

Answer 3

Entire muscle: Adduction, internal rotation

Clavicular and sternocostal parts: flexion; assist in respiration when shoulder is fixed

Question 4

What is the origin of the pectoralis minor?

Answer 4

3rd-5th ribs

Question 5

what is the insertion of the pectoralis minor?

Answer 5

coracoid process

Question 6

what is the innervation of the pectoralis minor?

Answer 6

medial pectoral n. (C8, T1)

Question 7

What is the action of the pectoralis minor?

Answer 7

anterior tilt, protracts scapula, depresses scapula when elevated

Question 8

What is the origin of the serratus anterior (serratus part, intermediate part, inferior part)?

Answer 8

1st-9th ribs

Question 9

What is the insertion of the serratus anterior (superior part, intermediate part, inferior part)?

Answer 9

Scapula (medial border)

Question 10

What is the innervation of the serratus anterior (superior, intermediate, and inferior part)

Answer 10

Long thoracic n. (C5-C7)

Question 11

What is the action of the serratus anterior superior part?

Answer 11

adducts the arm

Question 12

What is the action of the serratus anterior intermediate part?

Answer 12

Entire muscle: Draws scapula laterally forward; elevates ribs when shoulder is fixed

Protracts scapula

Question 13

What is the action of the serratus anterior inferior part?

Answer 13

Protracts scapula

Question 14

What is the origin of the subclavius?

Answer 14

1st rib

Question 15

What is the insertion of the subclavius?

Answer 15

Clavicle (inferior surface)

Question 16

What is the innervation of the subclavius?

Answer 16

N. to subclavius (C5, C6)

Question 17

What is the action of the subclavius?

Answer 17

Steadies the clavicle in the sternoclavicular joint

Question 18

What is the origin of the deltoid clavicular part?

Answer 18

lateral one third of clavicle

Question 19

what is the insertion of the deltoid?

Answer 19

humerus (deltoid tuberosity)

Question 20

What is the innervation of the deltoid?

Answer 20

Axillary n. (C5,C6)

Question 21

What is the action of the deltoid, clavicular part?

Answer 21

Flexion, internal rotation, adduction.

Question 22

What is the origin of the deltoid acromial part?

Answer 22

Acromion

Question 23

What is the action of the deltoid acromial part?

Answer 23

Abduction

Question 24

What is the origin of the deltoid spinal part?

Answer 24

scapular spine

Question 25

What is the action of the deltoid spinal part?

Answer 25

extension, external rotation, adduction

Question 26

What is the origin of the latissimus dorsi?

Answer 26

Iliac crest, 9th-12th ribs, Scapula (inferior angle), spinous process of T7-T12 vertebrae; thoracolumbar fascia

Question 27

What is the insertion of the latissimus dorsi?

Answer 27

Floor of the intertuberculargroove of the humerus

Question 28

What is the innervation of the latissimus dorsi?

Answer 28

Thoracodorsal n. (C6-C8)

Question 29

What is the action of the latissimus dorsi?

Answer 29

Internal rotation, adduction, extension, respiration

Question 30

What is the origin of the sternocleidomastoid sternal head?

Answer 30

sternum (manubrium)

Question 31

What is the insertion of the sternocleidomastoid?

Answer 31

Temporal bone (mastoid process), Occipital bone (superior nuchal line)

Question 32

What is the innervation of the sternocleidomastoid?

Answer 32

Motor: Accessory n. (CN XI) Pain and Proprioception: Cervical plexus (C2, C3)

Question 33

What is the action of the sternocleidomastoid?

Answer 33

Unilaterally: Tilts head to same side, rotates head to opposite side Bilateral: Extends head, aids in respiration when head is fixed

Question 34

What is the origin of the pectoralis major?

Answer 34

Clavicular part: Clavicle (medial half) Sternocostal part: sternum and costal cartilages 1-6 Abdominal part: rectus sheath (anterior layer)

Question 35

What is the origin of the sternocleidomastoid clavicular head?

Answer 35

Clavicle (medial one third)

Question 36

What is the origin of the anterior scalene?

Answer 36

C3-C6 (anterior tubercles of transverse processes)

Question 37

What is the insertion of the anterior scalene?

Answer 37

1st rib (scalene tubercle)

Question 38

What is the origin of the middle scalene?

Answer 38

C1-C2 (transverse processes), | C3-C7 (posterior tubercles of transverse processes)

Question 39

What is the insertion of the middle scalene?

Answer 39

1st rib (posterior to groove for subclavian artery)

Question 40

What is the origin of the posterior scalene?

Answer 40

C5-C7 (posterior tubercles of transverse processes)

Question 41

What is the insertion of the posterior scalene?

Answer 41

2nd rib (outer surface)

Question 42

What is the innervation of the scalenes?

Answer 42

Direct branches from cervical and brachial plexuses (C3-C8)

Question 43

What is the action of the scalenes?

Answer 43

With ribs mobileElevates upper ribs (during forced inspiration) With ribs fixed: Bends cervical spine to same side (Unilateral), Flexes neck (bilateral)

Question 44

What is the origin of the omohyoid?

Answer 44

Superior border of the scapula

Question 45

insertion of omohyoid?

Answer 45

hyoid bone

Question 46

innervation of omohyoid?

Answer 46

ansa cervicalis of cervical plexus (C1-C3)

Question 47

action of omohyoid?

Answer 47

depresses hyoid and larynx (for phonation and terminal phases of swallowing)

Question 48

What is the insertion of the omohyoid?

Answer 48

Hyoid bone

Question 49

What is the innervation of the omohyoid?

Answer 49

Ansa cervicalis of cervical plexus (C1-C3)

Question 50

What are the actions of the omohyoid?

Answer 50

Depresses hyoid and larynx (for phonation and terminal phases of swallowing)