Muscles of the Rotator Cuff and Shoulder Joint

Question 1

Deltoid ori and ins

Answer 1

Ori:
Lateral clavicle (anterior fibers)
Acromion (lateral fibers)
Spine of scapula (posterior fibers)

Ins: Deltoid tuberosity of humerus

Question 2

deltoid function (5)

Answer 2

• flexion of shoulder joint (ant fibers)
• medial rotation of shoulder joint (ant fibers)
• extension of shoulder joint (post fibers)
• lateral rotation of the shoulder joint (post fibers)
• abduction of the shoulder joint (entire muscle)

Question 3

innervation of deltoid

Answer 3

N: Axillary

Question 4

Subscapularis innervation

Answer 4

Upper and lower subscapularis

Question 5

Subscapularis

Answer 5

Ori: Subscapular fossa

Ins: Lesser tubercle of humerus

Question 6

Subscapularis function

Answer 6

medial rotation of the shoulder joint

Question 7

Supraspinatus innvervation

Answer 7

N: Suprascapular

Question 8

Supraspinatus function

Answer 8

abduction of the shoulder joint

Question 9

Supraspinatus ori and ins

Answer 9

Ori: Supraspinous fossa

Ins: Greater tubercle of humerus

Question 10

Infraspinatus ori and ins

Answer 10

Ori: Infraspinous fossa
Ins: Greater tubercle of humerus

Question 11

Infraspinatus function (1)

Answer 11

lateral rotation of the shoulder joint

and maybe:
horizontal abduction of the shoulder joint

Question 12

Infraspinatus innervation

Answer 12

N: Suprascapular

Question 13

Teres Minor ori and ins

Answer 13

Ori: The superior lateral border of scapula
Ins: Greater tubercle of humerus

Question 14

Teres Minor innervation

Answer 14

N: Axillary

Question 15

Teres Minor function

Answer 15

lateral rotation of the shoulder joint

Question 16

Teres Major ori and ins

Answer 16

Ori: The inferior lateral border of scapula
Ins: Medial lip of intertubercular (bicipital) sulcus (groove) of humerus

Question 17

Teres Major innervation

Answer 17

N: Upper & lower subscapular

Question 18

Teres Major function

Answer 18

• extension of the shoulder joint
• adduction of the shoulder joint
• medial rotation of the shoulder joint

Question 19

Rotator Cuff Muscles Includes 4 Muscles: (SITS)

Answer 19

Supraspinatus
Infraspinatus
Teres Minor
Subscapularis

Question 20

They strengthen the shoulder joint capsule all around except ________. This explains why dislocations of the humerus occur most commonly in a downward direction.

Answer 20

inferiorly

Question 21

Axillary spaces: Triangular space

Answer 21

Circumflex
scapular A.

Question 22

Axillary spaces: Quadrangular space

Answer 22

Axillary N.
Posterior humeral circumflex A.

Question 23

Axillary spaces: Triangular interval

Answer 23

Radial N.
Profunda brachii A.