Muscles of the Shoulder, Arm, Forearm, and Hand

Question 1

Trapezius

origin, insertion, and action

Answer 1

origin: C7-T12
insertion: clavicle
action: extends and abducts head

Question 2

Deltoid

origin, insertion, action, synergist, and antagonist

Answer 2

origin: clavicle
insertion: deltoid tuberosity of the humerus
action: abducts arm
synergist: Pectoralis major (flexion of the arm)
antagonist: Pectoralis major (which adducts the arm)

Question 3

Pectoralis major

origin, insertion, action, synergist, and antagonist

Answer 3

origin: clavicle
insertion: crest of greater tubercle of humerus
action: flexes, adducts arm
synergist: Deltoid (flexion of the arm)
antagonist: Deltoid (which abducts the arm)

Question 4

Pectoralis minor

origin, insertion, and action

Answer 4

origin: ribs 3-5
insertion: coracoid process of scapula
action: depresses glenoid cavity and raises ribs 3-5

Question 5

Latissimus dorsi

origin, insertion, action, synergist, and antagonist

Answer 5

origin: T7-12
insertion: intertubercular groove of humerus
action: extends arm
synergist: Pectoralis major (adduction of the arm)
antagonist: Pectoralis major (which flexes the arm)

Question 6

Supraspinatus

action, synergist, antagonist

Answer 6

action: abducts arm
synergist: Infraspinatus (stabilization of the shoulder joint)
antagonist: Teres major (which adducts the arm)

Question 7

Infraspinatus

action, synergist, antagonist

Answer 7

action: laterally rotates arm
synergist: Supraspinatus (stabilization of the shoulder joint)
antagonist: Subscapularis (medially rotates arm)

Question 8

Subscapularis

action, synergist, antagonist

Answer 8

action: medially rotates arm
synergist: Supraspinatus (stabilization of the shoulder joint)
antagonist: Infraspinatus (laterally rotates arm)

Question 9

Teres minor

action, synergist, antagonist

Answer 9

action: laterally rotates arm
synergist: Supraspinatus (stabilization of the shoulder joint)
antagonist: Subscapularis (medially rotates arm)

Question 10

Teres major

action, synergist, antagonist

Answer 10

action: extends and medially rotates arm
synergist: Subscapularis (medially rotates arm)
antagonist: Infraspinatus (laterally rotates arm)

Question 11

Biceps brachii

action, synergist, antagonist

Answer 11

action: flexes arm
synergist: Coracobrachialis (flexes arm)
antagonist: Triceps brachii (extends arm)

Question 12

Triceps brachii

action, synergist, antagonist

Answer 12

action: extends arm, adducts arm
synergist: Coracobrachialis (adducts arm)
antagonist: Biceps brachii (flexes arm)

Question 13

Coracobrachialis

action, synergist, antagonist

Answer 13

action: flexes arm
synergist: Biceps brachii (flexes arm)
antagonist: Triceps brachii (extends arm)

Question 14

Brachialis

action, synergist, antagonist

Answer 14

action: flexes forearm
synergist: Brachioradialis (flexes forearm)
antagonist: Triceps brachii (extends forearm)

Question 15

Brachioradialis

action, insertion, antagonist

Answer 15

action: flexes forearm
synergist: Brachialis (flexes forearm)
antagonist: Triceps brachii (extends forearm)