muscles of the shoulder region (scapular muscles)

Question 1

Innervation of deltoid is

Answer 1

circumflex (axillary) nerve (C5,6)

Question 2

Action of deltoid muscle

Answer 2

anterior fibers flex and medially rotates the arm
posterior fibers extend and laterally rotates the arm
middle fibers abduct the arm from 15 to 90 degrees

Question 3

Deltopectoral groove lodges…..,….and…..

Answer 3

uppermost part of cephalic vein
deltoid branch of thoraco-acromial artery
deltopectoral lymph nodes

Question 4

nerve supply of supraspinatus

Answer 4

suprascapular nerve (C5,6)

Question 5

Action of supraspinatus

Answer 5

Helps to steady the head of the humerus in the glenoid cavity
abducts the arm from 0 to 15 (initiates abduction)

Question 6

Innervation of infraspinatus

Answer 6

supscapular nerve (C5,6)

Question 7

Action of infraspinatus

Answer 7

Steadies the head of the humerus
Rotates the arm laterally

Question 8

Nerve supply of teres minor

Answer 8

axillary( circumflex) nerve (C5,6)

Question 9

Action of teres minor…..,…..and…..

Answer 9

Steadies the head of the humerus, adducts and rotates the arm

Question 10

Nerve supply of Teres major

Answer 10

lower subscapular nerve (C5,6)

Question 11

Teres major action …,….and…..

Answer 11

adduction, medial rotation and extension of the arm.

Question 12

Innervation of teres minor

Answer 12

axillary (circumflex) nerve (C 5,6)

Question 13

Teres minor action….,…and….

Answer 13

steadies the head of the humerus
adducts and laterally rotates the arm

Question 14

any muscle attached to a fossa is attached to its middle two thirds

Question 15

Innervation of subscapularis

Answer 15

upper and lower subscapular nerves (C 5,6)

Question 16

subscapularis action……,…and….

Answer 16

stabilization of the anterior aspect of the shoulder joint
medial rotation and adduction of the arm

Question 17

Subscapularis together with the supraspinatus , infraspinatus and teres minor steady the head of the humerus in the glenoid cavity during movements of the arm .
Tendons of these 4 muscles blend with the capsule of the shoulder joint and are called the “rotator muscle cuff”