Shoulder - Action

Question 1

Pectoralis Major (2)

Answer 1

horizontal ADDuction
IR of humerus

Heads acting alone:
– clavicular portion flx humerus
– sternocostal head ext humerus

Question 2

Pectoralis minor

Answer 2

pulls shoulder girdle anteriorly and inferiorly (stabilizes scapula against thoracic wall)

Question 3

Serratus anterior

Answer 3

protracts scapula (stabilizes and rotates scapula so that glenoid fossa faces sup)

Question 4

Upper trapezius (2)

Answer 4

elevation of scapula
upward rotation of scapula

Question 5

Middle trapezius

Answer 5

retraction of scapula

Question 6

Lower trapezius (2)

Answer 6

depression of scapula
upward rot of scapula

Question 7

Latissimus dorsi (3)

Answer 7

adduction
extension
IR of humerus

Question 8

Levator scapulae (2)

Answer 8

elevation and inferior rot of scapula

also plays role in head posture

Question 9

Rhomboid major & minor (2)

Answer 9

retract and stabilize scapula

Inferior rotation of scapula; glenoid faces caudal

Question 10

Anterior deltoid (2)

Answer 10

forward flexion

IR of humerus

Question 11

Middle deltoid

Answer 11

abduction of the humerus

Question 12

Posterior deltoid (2)

Answer 12

extension
ER of humerus

Question 13

Teres major (3)

***same as lats

Answer 13

adduction
extension
IR of humerus

Question 14

Teres minor (2)

Answer 14

ER of humerus

GHJ dynamic stabilization

Question 15

Supraspinatus (2)

Answer 15

initiates first 5-15 degrees abduction of humerus

GHJ dynamic stabilization

Question 16

Infraspinatus (2)

Answer 16

ER of humerus

GHJ dynamic stabilization

Question 17

Subscapularis (3)

Answer 17

IR and ADD of humerus

GHJ stabilization