Shoulder

Question 1

What are the muscles of the pectoral region, where do they originate?

Answer 1

pectoralis major, pectoralis minor, serratus anterior

they originate on the anterior aspect of the axial skeleton

Question 2

What innervate the muscles of the pectoral region?

Answer 2

C6-C8

Question 3

Where does pectoralis major insert?

Answer 3

onto the proximal humeral shaft

Question 4

Innervation of pectoralis major

Answer 4

medial and lateral pectoral nn.

Question 5

Actions of pectoralis major

Answer 5

adduction, flexion and medial rotation of GHJ

Question 6

Attachments of pectoralis minor

Answer 6

origin: ribs 3-5
insertion: coracoid process of the scapula

Question 7

Actions of pectoralis minor

Answer 7

protraction of and depression of the scapula

Question 8

What innervates pectoralis minor?

Answer 8

medial pectoral n. (medial does more)

Question 9

Attachments of serratus anterior

Answer 9

origin: lateral aspect of ribs 1-8
insertion: anterior surface of medial border of scapula

Question 10

Actions of serratus anterior

Answer 10

protraction and upward rotation of scapula, fixes scapula on thoracic wall

Question 11

Innervation of serratus anterior

Answer 11

long thoracic n.

Question 12

What will occur if there is injury to the long thoracic nerve?

Answer 12

pt will have winged scapula because serratus anterior will not be able to hold the scapula against the thoracic wall

Question 13

What supplies blood to the pectoral region?

Answer 13

Axillary artery, gives off thoracoacromial a. and lateral thoracic a.

Question 14

thoracoacromial artery

Answer 14

supplies pectoral muscles and deltoid

Question 15

lateral thoracic artery

Answer 15

supplies serratus anterior and pectoral muscles

Question 16

What are the extrinsic muscles of the back?

Answer 16

trapezius, levator scapulae, rhomboid minor/major, latissimus dorsi

Question 17

What innervates the extrinsic muscles of the back?

Answer 17

C5-7

CN XI

Question 18

Actions of trapezius?

Answer 18

superior fibers: elevation

middle fibers: retraction

inferior fibers: depression

superior + inferior: upward rotation

Question 19

innervation of trapezius?

Answer 19

cranial nerve XI

can be tested by asking pt to shrug shoulders against resistance

Question 20

Attachments of levator scapulae

Answer 20

origin: cervical transverse process
insertion: superior angle of scapula

Question 21

Actions of levator scapulae

Answer 21

elevate and downward rotation of scapula

Question 22

innervation of levator scapulae

Answer 22

dorsal scapular n.

Question 23

attachments of rhomboid minor and major

Answer 23

origin: nuchal ligament and thoracic spinous process
insertion: medial border of scapula

Question 24

Actions of rhomboid minor and major:

Answer 24

retraction and downward rotation (fixes scapula on body wall)

Question 25

Innervation of rhomboid minor and major

Answer 25

dorsal scapular n.

Question 26

attachments of latissimus dorsi

Answer 26

origin: thoracolumbar fascia, iliac crest, ribs insertion: anteromedial aspect of proximal humerus

Question 27

actions of latissimus dorsi

Answer 27

extension, adduction and medial rotation of GH joint

Question 28

Innervation of latissimus dorsi

Answer 28

thoracodorsal n.

Question 29

What are the intrinsic muscles of the shoulder?

Answer 29

deltoid teres major rotator cuff muscles: supraspinatous, infraspinatous, teres minor, subscapularis originate on scapula, insert on humerus

Question 30

What innervates the intrinsic muscles of the shoulder?

Answer 30

C5-C6

Question 31

Actions of deltoid muscle?

Answer 31

Anterior portion: flexion and medial rotation of GHJ middle: abduction of GHJ (after initial 15deg) posterior: extension and lateral rotation

Question 32

Innervation of deltoid

Answer 32

axillary n.

Question 33

How can you test the axillary n. ?

Answer 33

motor: palpate deltoid while abducting against resistance sensory: loss of sensation on lateral aspect of shoulder

Question 34

Attachments of teres major

Answer 34

origin: inferior angle of scapula insertion: proximal humeral shaft

Question 35

Actions of teres major?

Answer 35

medial rotation and adduction of GHJ

Question 36

Innervation of teres major

Answer 36

lower subscapular n.

Question 37

Rotator cuff

Answer 37

musculotendinous cuff that stabilizes the GHJ SITS muscles - supraspinatus - infraspinatous - teres minor - subscapularis

Question 38

Action of supraspinatus

Answer 38

Abduction of GHJ (initial 15deg, then deltoid takes over)

Question 39

innervation of supraspinatus

Answer 39

suprascapular n.

Question 40

Action of infraspinatus

Answer 40

lateral rotation of GHJ

Question 41

Innervation of infraspinatus

Answer 41

suprascapular n.

Question 42

Action of teres minor

Answer 42

Lateral rotation of GHJ

Question 43

Innervation of teres minor

Answer 43

axillary n.

Question 44

Attachments of subscapularis

Answer 44

origin: subscapular fossa of the scapula insertion: lesser tubercle of the humerus

Question 45

Action of subscapularis

Answer 45

medial rotation and adduction of GHJ

Question 46

Innervation of subscapularis

Answer 46

upper and lower subscapular nn.

Question 47

Blood supply of the posterior shoulder:

Answer 47

Subclavian artery gives rise to thyrocervical truck which gives off -Transverse cervical a. (superficial branch and dorsal scapular a. ) -suprascapular a very large anastomoses so if arterial supply is lost from one artery, there are others that can take over

Question 48

What is meant by Army over Navy?

Answer 48

suprascapular artery courses over the superior transverse scapular ligament while the suprascapular nerve passes under the superior transverse scapular ligament

Question 49

Venous drainage of posterior shoulder?

Answer 49

transverse cervical vein > suprascapular vein> external jugular vein> subclavian vein

Question 50

If the dorsal scapular nerve is damaged, which muscles are most likely to be affected?

Answer 50

rhomboid minor, rhomboid major and levator scapulae