Week 8 - Scapulohumeral muscles

Question 1

How many scapulohumeral muscles are there?

Answer 1

Six

Question 2

Name the six scapulohumeral muscles

Answer 2

Deltoid
Teres major
Supraspinatus
Infraspinatus
Subscapularis
Teres minor

Question 3

What are scapulohumeral muscles?

Answer 3

Relatively short muscles that pass from the scapula to the humerus and act on the glenohumeral joint

Question 4

What is the deltoid muscle?

Answer 4

A thick, powerful, coarse-textured muscle covering the shoulder and forming its surrounded contour

Question 5

What happens when all three parts of the deltoid contract simultaneously?

Answer 5

The arm is abducted

Question 6

What do the anterior and posterior parts of the deltoids do?

Answer 6

Steady the arm as it is abducted

Question 7

What assists the deltoid to initiate movement during the first 15 degrees of abduction?

Answer 7

The supraspinatus

Question 8

When the arm is fully adducted, what must abduction be intitiated by?

Answer 8

The supraspinatus, or leaning to the side, allowing gravity to initiate the movement

Question 9

When does the deltoid become fully effective as and abductor?

Answer 9

After the first 15 degrees of initial abduction

Question 10

What are the anterior and posterior parts of the deltoid used for?

Answer 10

To swing the limbs during walking

Question 11

What part of the deltoid assists the pectoralis major in flexing the arm?

Answer 11

The anterior part

Question 12

What part od the deltoid assists the latissimus dorsi in extending the arm?

Answer 12

The posterior part

Question 13

What holds the head of the humerus in the glenoid cavity during movements of the upper limb?

Answer 13

The deltoid

Question 14

What is the teres major?

Answer 14

A thick, rounded muscle passing laterally from the inferolateral third of the scapula

Question 15

What does the inferior border of the teres major form?

Answer 15

The inferior border of the lateral part of the posterior wall of the axilla

Question 16

What does the teres major do to the arm?

Answer 16

Adducts and medially rotates it
It can also help extend it from the flexed position and is an important stabalizer of the humeral head in the glenoid cavity - that is, it steadies the head in its socket

Question 17

What are the for muscles that are called rotator cuff muscles?

Answer 17

Supraspinatus
Infraspinatus
Teres minor
subscapular

Question 18

What is the only muscle of the rotator cuff that is a rotator of the humerus

Answer 18

The supraspinatus

Question 19

What does the supraspinatus do besides being part of the rotator cuff?

Answer 19

Initiates and assists the deltoid in the first 15 degrees of abduction of the arm

Question 20

Where does the supraspinatus occupy?

Answer 20

The supra spinous fossa of the scapula

Question 21

What separates the supraspinatus from the lateral quarter of the fossa

Answer 21

A bursa

Question 22

Where does the infraspinatus occupy?

Answer 22

The medial three quarters of the infraspinous fossa

Question 23

What partly covers the infraspinatus?

Answer 23

The deltoid and trapezius

Question 24

What does the infraspinatus do in addition to helping to stabalize the glenohumeral joint?

Answer 24

It is a powerful lateral rotator of the humerus

Question 25

What is the teres minor?

Answer 25

A narrow , elongate muscle that is completely hidden by the deltoid and is often not clearly delineated from the infraspinatus

Question 26

What does the teres minor do?

Answer 26

Works with the infraspinatus to rotate the arm laterally and assists in adduction

Question 27

What nerve supplies the teres minor?

Answer 27

The axillary nerve

Question 28

What nerve supplies the spinatus ?

Answer 28

The suprascapular nerve

Question 29

What is the subscapularis?

Answer 29

A thick, triangular muscle that lies on the costal surface of the scapula and forms part of the posterior wall of the axilla

Question 30

What aspect of the scapulohumeral joint does the subscapularis cross on its way to the humerus?

Answer 30

The anterior aspect

Question 31

What is the primary medial rotator of the arm and also adducts it?

Answer 31

The subscapularis