Muscles Of The Shoulder And Arm

Question 1

Origin, insertion, and action of Trapezius

Answer 1

Origin: Posterior occipital bone, C7-T12
Insertion: Clavicle, acromion process, and spine of scapula
Action: Extends and abducts head, rotates and adducts scapula

Question 2

Origin, insertion, and action of Deltoid

Answer 2

Origin: Clavicle, acromion process, spine of scapula
Insertion: Deltoid tuberosity of humerus
Action: Abducts arm; flexes, extends, medially, and laterally rotates arm

Question 3

Origin, insertion, and action of Pectoralis major

Answer 3

Origin: Clavicle, sternum, cartilages of ribs 1-7
Insertion: Crest of greater tubercle of humerus
Action: Flexes, adducts, and medially rotates arm

Question 4

Origin, insertion, and action of Latissimus dorsi

Answer 4

Origin: T7-S5, crest of ilium, ribs 10-12
Insertion: Intertubercular groove of humerus
Action: Extends, adducts, and medially rotates arm; draws shoulder inferiorly

Question 5

Origin, insertion, and action of Biceps brachii

Answer 5

Origin:
1. Long head: superior margin of glenoid fossa
2. Short head: coracoid process of scapula
Insertion: Radial tuberosity
Action: Flexes arm, flexes forearm, supinates hand

Question 6

Origin, insertion, and action of Triceps brachii

Answer 6

Origin: Infraglenoid tuberosity of scapula, lateral and posterior surface of humerus
Insertion: Olecranon process, tuberosity of ulna
Action: Extends and adducts arm, extends forearm

Question 7

Name an action of the Pectoralis minor

Answer 7

Depresses glenoid cavity, raises ribs 3-5

Question 8

Name an action of the Supraspinatus

Answer 8

Abducts arm, helps stabilize shoulder joint

Question 9

Name an action of the Infraspinatus

Answer 9

Laterally rotates arm, stabilizes shoulder joint

Question 10

Name an action of the Subscapularis

Answer 10

Medially rotates arm, stabilizes shoulder joint

Question 11

Name an action of the Teres minor

Answer 11

Laterally rotates and adducts arm, stabilizes shoulder joint

Question 12

Name an action of the Teres major

Answer 12

Extends, adducts, and medially rotates arm

Question 13

Name an action of the Coracobrachialis

Answer 13

Flexes and adducts arm

Question 14

Name an action of the Brachialis

Answer 14

Flexes forearm

Question 15

Name an action of the Brachioradialis

Answer 15

Flexes forearm

Question 16

Name the superficial muscles of the shoulder (5)

Answer 16

1. Trapezius
2. Deltoid
3. Pectoralis major
4. Pectoralis minor
5. Latissimus dorsi

Question 17

Name the deep muscles of the shoulder (5)

Answer 17

1. Supraspinatus
2. Infraspinatus
3. Subscapularis
4. Teres minor
5. Teres major

Question 18

Define an intrinsic muscle

Answer 18

A muscle contained within the region it moves

Question 19

Define and extrinsic muscle

Answer 19

A muscle located outside of the region it moves

Question 20

Define aponeurosis

Answer 20

A broad flat tendon

Question 21

What is the purpose of a retinaculum?

Answer 21

Anchors tendons

Question 22

Define fascia

Answer 22

Outer muscle wrapping

Question 23

Name the muscles of the rotator cuff (4)

Answer 23

1. Supraspinatus
2. Infraspinatus
3. Teres minor
4. Subscapularis