Scapular and Pectoral Regions

Question 1

is the sternum part of the pectoral girdle?

Answer 1

no

Question 2

what are the three joints of the shoulder complex?

Answer 2

1. sternocalvicular jt
2. acromioclavicular jt
3. glenohumeral jt

Question 3

what are the movements of the glenohumeral jt?

Answer 3

flexion, extension, abduction, adduction, med/lat rotation, circumduction

Question 4

muscles of pectoral girdle

Answer 4

1. deltoid m
2. teres major m
3. supraspinatus m
4. infraspinatus m
5. teres minor m
6. subscapularis m

Question 5

muscles of rotator cuff

Answer 5

1. supraspinatus
2. infraspinatus
3. teres minor
4. subscapularis

Question 6

A and N of deltoid m

Answer 6

A: abducts humerus, flexes, extends, and rotates humerus
N: axillary n, post circumflex humeral vessels

Question 7

A and N of teres major m

Answer 7

A: medially rotates and extends humerus
N: lower (inferior) subscapular n, and scapular vessels

Question 8

A and N of supraspinatus

Answer 8

A: abducts humerus (1st 15 degrees) *still helps even when deltoid takes over)
N: suprascapular n and vessels, dorsal scapular vessels

Question 9

A and N of infraspinatus

Answer 9

A: laterally rotates humerus
N: suprascapular n and vessels, subscapular vessels

Question 10

A and N of teres minor m

Answer 10

A: lateral rotation of humerus
N: axillary n, suprascapular and subscapular vessels

Question 11

A and N of subscapularis

Answer 11

A: medial rotation of humerus
N: upper and lower subscapular nn, subscapular vessels

Question 12

protection of shoulder region

Answer 12

deltoid provides outer muscular support

rotator cuff gives inner muscular support (helps prevent upward displacement of humerus)

Question 13

location of subacromial/deltoid bursa

Answer 13

inferior to acromion and deltoid but superior to supraspinatus

Question 14

issues with subacromial/deltoid bursa

Answer 14

can become continuous with jt capsule bc attrition of supraspinatus tendon (tendon wears away with age, if capsule ruptures (continuous w/ bursa) = painful shoulder movement and limited movement

Question 15

borders of quadrangular space

Answer 15

sup: teres minor
inf: teres major
med: long head of triceps
lat: surgical neck of humerus

Question 16

contents of quadrangular space

Answer 16

axillary n, post circ humeral vessels

Question 17

borders of triangular space

Answer 17

sup: teres minor
inf: teres major
lat: long head of triceps

Question 18

contents of triangular space

Answer 18

circumflex scapular vessels

Question 19

borders of triangular interval

Answer 19

sup: teres major
med: long head of triceps
lat: lateral head of triceps

Question 20

contents of triangular interval

Answer 20

radial n and profunda brachii a

Question 21

neurovascular supply of shoulder region

Answer 21

suprascapular n and a
dorsal scapular n and a
accessory n and transverse cervical a
upper and lower subscapular nn and subscapular a

Question 22

suprascapular n and a, and supply

Answer 22

n: ventral rami of C5-C6 *runs under superior trans scap lig
a: thyrocervical trunk *runs over sup trans scap lig
s: supra/infraspinatus mm

Question 23

dorsal scapular n and trans cervical a: n, a, supply

Answer 23

n: ventral rami of C5
a: deep trans cerv a *both run II to vertebral border of scapula
s: levator scapulae and rhomboid mm

Question 24

accessory n and trans cervical a: n, a, supply

Answer 24

n: CN XI
a: superficial trans cervical a, br of thyrocervical tr.
s: trapezius mm

Question 25

upper and lower subscapular nn and subscapular a: n, a, s

Answer 25

n: post cord of brachial plexus (vent rami C5-C6)
a: axillary a -> subscapular a (splits to thoracodorsal and circumflex scapular a)
S: subscapularis m

lower supplies teres minor

Question 26

what exhibits collateral circulation in the scapular region, and where?

Answer 26

axillary a, ligates between thyrocervical tr and subscapular a

Question 27

what does collateral circulation in the scapular region do?

Answer 27

blood flow in subscapular a reverses, allows blood to flow to UL

ligate anywhere distal to subscapular a and blood cannot flow

Question 28

pectoral region

Answer 28

m attachment between UP and anterior chest

Question 29

mm of pectoral region

Answer 29

pec minor
pec major (clavicular and sternocostal heads)

Question 30

pec major m

Answer 30

A: adducts and medially rotates humerus
N: med and lat pectoral nn and thoracoacromial vessels

Question 31

pec minor m

Answer 31

A: protracts scapula
N: medial pectoral n and thoracoacromial vessels

Question 32

arterial supply of pectoral regions

Answer 32

1. internal thoracic (mammary) a
2. lateral thoracic (external mammary) a
3. thoracoacromial a

Question 33

internal thoracic (mammary) a

Answer 33

br of subclavian a, descends across intercostal spaces lateral to sternum
supplies ant thorax, med pec region and med breast

Question 34

lateral thoracic a

Answer 34

br of axillary a (deep to pec minor), runs with long thoracic n
supplies lat thorax, lat pec region, lat breast

Question 35

thoracoacromial a

Answer 35

br of axillary a (under pec minor)

sends 4 brs

Question 36

4 branches of thoracoacromial a

Answer 36

1. acromial a: supplies upper shoulder region
2. clavicular a: clavicle region
3. pectoral a: upper pec region
4. deltoid a: lower shoulder region

Question 37

pectoral region innervation

Answer 37

1. cutaneous nn
2. medial pectoral n
3. lateral pectoral n
4. long thoracic n

Question 38

cutaneous nn

Answer 38

general sensory, T1-T6, lat and ant cutaneous brs of intercostal nn

Question 39

medial pectoral n

Answer 39

medial cord of BP, from vent rami (C8-T1), pierces pec minor m to enter pec major, supplies pec minor and part of major

Question 40

lateral pectoral n

Answer 40

lat cord of BF, ventral rami (C5-C6), runs above pec minor m to enter pec major, supplies remainder of pec major

Question 41

long thoracic n

Answer 41

from vent rami (C5-C7), supplies serratus ant , superficially, damage to long thoracic n can occur during mastectomy -> winged scapula