Muscles Acting on the Arm Posterior Group

Question 1

Deltoid (lateral and posterior part)

Answer 1

O: Scapula
I: Humerus
A: Flexes, extends, abducts, and laterally rotates arm
N: Axillary nerve

Question 2

Supraspinatus

Answer 2

O: Scapula
I: Greater tubercle of the humerus
A: Assists in arm abduction, stabilizes shoulder joint
N: Suprascapular nerve

Question 3

Infraspinatus

Answer 3

O: Scapula
I: Greater tubercle of the humerus
A: Laterally rotates arm, stabilizes shoulder joint
N: Suprascapular nerve

Question 4

Teres minor

Answer 4

O: Scapula
I: Greater tubercle of the humerus
A: Laterally rotates arm, stabilizes shoulder joint
N: Suprascapular nerve

Question 5

Subscapularis

Answer 5

O: Scapula
I: Lesser tubercle of the humerus
A: Medially rotates arm, stabilizes shoulder joint
N: Subscapular nerve

Question 6

Teres major

Answer 6

O: Scapula
I: Humerus
A: Extends, adducts, and medially rotates arm
N: Subscapular nerve

Question 7

Triceps brachii long head

Answer 7

O: Scapula
I: Ulna
A: Extends and assists in arm adduction
N: Radial nerve

Question 8

Latissimuss Dorsi

Answer 8

O: Thoracic and lumbar vertebrae, ribs, iliac crest
I: Humerus
A: Extends, adducts, and medially rotates arm
N: Thoracodorsal nerve