Shoulder muscles

Question 1

Name all the muscles of the shoulder girdle?

Answer 1

• Trapezius (lower, middle, upper).
• Levator scapulae
• Rhomboid major
• Rhomboid minor
• Serratus anterior (upper + lower)
• Pectoralis minor

Question 2

About trapezius- upper?

Answer 2

• Attached to occipital bone and lateral clavicle.

- Elevates shoulder and stabilises when carrying.

Question 3

About trapezius- lower?

Answer 3

• Attached to lower thoracic vertebrae and spine of scapula.
• Depress the scapula.

Question 4

About trapezius- middle?

Answer 4

• Attahces to 7th cervical vertebrae and spine of scapula.

- Retracts the scapula.

Question 5

Action of upper and lower trapezius?

Answer 5

• Laterally rotate scapula

- Turn glenoid cavity up

Question 6

About levator scapulae?

Answer 6

• Attaches to 1-4th cervical, medial border of spine of scapula and deep to upper trapezius.
• Elevates and medially rotates scapula.

Question 7

Rhomboid major and minor?

Answer 7

-Attaches to 7th cervical and upper thoracic + medial border of scapula.
Lies deep to middle traps.
-Retract and medially rotate scapula.

Question 8

Serratus anterior - upper?

Answer 8

• Attaches to 1st-8th ribs and medial border of scapula.
• Protracts scapula.
• Stabilises scapula when weight carried (stops winged scapula).

Question 9

Serratus anterior- lower?

Answer 9

• Attaches to 5-8th ribs and lower medial border of scapula.
• Laterally rotates scapula.

Question 10

Pectoralis minor?

Answer 10

• Attches to 3-5th ribs and coracoid process of scapula.

- Protracts and depress and medially rotate scapula.

Question 11

Subclavius?

Answer 11

• Attaches to 1st rib and costal cartilage, and lower clavicle.
• Stabilises and depresses clavicle.

Question 12

Name the muscles that stabilise the GH joint?

Answer 12

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Question 13

Supraspinatus?

Answer 13

• Attaches to supraspinous fossa of scapula and humerus.

- Stabilises and abducts GH joint.

Question 14

Infraspinatus?

Answer 14

• Attaches to infraspinous fossa of scapula and humerus.

- Stabilises and laterally rotates GH joint.

Question 15

Teres minor?

Answer 15

• Attaches to upper aspect of scapula and humerus.

- Stabilises, laterally rotates and weakly adducts GH joint.

Question 16

Subscapularis?

Answer 16

• Attaches to surface of scapula and top of humerus.

- Stabilises and medially rotates GH joint.

Question 17

Name the muscles that move the GH joint?

Answer 17

• Deltoid (anterior, middle and posterior)
• Pectoralis major (upper and lower)
• Latissimus dorsi )upper, middle, lower)
• Teres major
• Coracobrachialis

Question 18

Deltoid - anterior fibres?

Answer 18

• Attches to lateral clavicle and lateral shaft of humerus.

- Flexes and medially rotates GH joint.

Question 19

Deltoid - posterior fibres?

Answer 19

• Attaches to spine of scapula and lateral humerus.

- Extends, laterally rotates and adducts joint.

Question 20

Deltoid - middle fibres?

Answer 20

• Attaches to acromion process of scapula and lateral humerus.
• Abducts GH joint.

Question 21

Pectoralis major - lower?

Answer 21

• Attaches to sternum and humerus.

- Extends the joint from flex.

Question 22

Pectoralis major - upper?

Answer 22

• Ataches to medial half of clavicle and humerus.

- Flexes GH from extension.

Question 23

Latissimus dorsi?

Answer 23

• Attaches to 7-12th thoracic, lower 3rd ribs and inferior angle of scapula.
• Extends GH and medially rotates against resistance.

Question 24

Teres major - weak action?

Answer 24

• Attaches to lateral border of scapula and humerus.

- Medially rotates, adducts and extends GH joint.

Question 25

Coracobrachialis - weak action?

Answer 25

• Attaches to coracoid process of scapula and mid shaft of humerus.
• Adducts and flexes GH.

Question 26

What about the biceps brachii tendon?

Answer 26

• Attaches to socket and to superior of humerus.

- Humeral ligament holds tendon in the groove.