Objective 2: Muscles of the Shoulder Region (Actions)

Question 1

Actions performed by Pectoralis Major

Answer 1

• SH Adduction and Medial rotation
• Clavicular: flex humerus to horizontal
• Sternal: extend flexed humerus

Question 2

Actions of Pectoralis Minor

Answer 2

protraction and downward rotation

Question 3

Actions performed by Serratus Anterior

Answer 3

protraction and upward rotation

Question 4

Actions of upper trapezius

Answer 4

• elevation of pectoral girdle
• lateral flexion of neck
• extension of the neck
• upward rotation

Question 5

middle trapezius actions

Answer 5

retraction

Question 6

lower trapezius actions

Answer 6

• depress pectoral girdle

- upward rotation

Question 7

latissimus dorsi actions

Answer 7

• extension of flexed arm
• adduction
• medial rotation

Question 8

levator scapulae actions

Answer 8

• elevation of the pectoral girdle
• retraction
• extension of neck
• lateral flexion of neck
• downward rotation

Question 9

rhomboid major/minor actions

Answer 9

• retraction

- downward rotation

Question 10

deltoid actions

Answer 10

• SH abduction

ant fibres: SH flex/med r

post fibres: SH extend/lat r

Question 11

supraspinatus actions

Answer 11

• abduction

Question 12

infraspinatus actions

Answer 12

lateral rotation

Question 13

teres minor actions

Answer 13

• lateral rotation

Question 14

teres major actions

Answer 14

adduction
medial rotation
extend flexed arm

Question 15

subscapularis

Answer 15

• medial rotation

- adduction