Exam #3 (Lecture 10: MM. that ADD/EXT Shoulder - IR/ER of Shoulder)

Question 1

what are the muscles that adduct and extend the shoulder? (5)
- innervations

Answer 1

posterior deltoid - axillary
lats - thoracodorsal
teres major - subscapular
long head of triceps brachii - C7, radial n.
sternocostal head of pec major - pectoral

Question 2

why is the sternocostal head of pec major partially flexed?

Answer 2

to extend back to anatomic position

Question 3

what two muscles assist with adducting and extending the shoulder?

Answer 3

infraspinatus
teres minor

Question 4

what activities require use of the adductors and extensors of the shoulder?

Answer 4

pulling (climbing a rope or swimming)
pullups (bring pelvis upward with humerus stable)

Question 5

what muscles work to stabilize the scapula?

Answer 5

rhomboids

Question 6

muscle interaction of the shoulder happens with scapulothoracic ___________ and glenohumeral _________

Answer 6

downward rotators
adductors

Question 7

where does the teres major internal moment arm extend from?

Answer 7

glenohumeral joint

Question 8

where does the rhomboids internal moment arm extend from?

Answer 8

scapula’s axis

Question 9

is internal or external rotation stronger?

Answer 9

internal

Question 10

what muscles internally rotate the shoulder?
- innervation

Answer 10

subscapularis - subscapular
pec major - pectoral
lats - thoracodorsal
teres major - subscapular
anterior deltoid - axillary

Question 11

what muscles externally rotate the shoulder?
- innervation

Answer 11

infraspinatus - suprascapular
teres minor - axillary
posterior deltoid - axillary

Question 12

which internal rotation muscle has the greatest moment of internal rotation? least moment of internal rotation?

Answer 12

subscapularis
anterior deltoid

Question 13

internal rotation has _________ mass and torque than external rotation

Answer 13

greater

Question 14

in throwing sports, you need a _______ internal torque which happens just before max external rotation.
it _______ decelerates

Answer 14

large
strongly

Question 15

external rotation requires the scapula to be ______

Answer 15

stable

Question 16

external rotation has _______ torque of all shoulder but ______ velocity

Answer 16

lowest max effort torque
high velocity

Question 17

generally for all muscle groups, eccentric generates _______ force than concentric

Answer 17

more

• lowering a heavy box is easier than lifting it