Muscles of the upper limbs

Question 1

Where does the coraco-brachialis originate and insert?

Answer 1

Originates = coracoid process of the scapula
Inserts = by means of a flat tendon into an impression at the middle of the medial surface of the humerus

Question 2

What innervates the coraco-brachialis?

Answer 2

The musculocutaneous nerve

Question 3

What are the three main functions of the coraco-brachialis muscle?

Answer 3

1. Shoulder flexion (bringing humerus forwards)
2. Shoulder adduction (bringing humerus towards torso)
3. Stabilises the humeral head in the shoulder joint

Question 4

Where does the serratus anterior muscle originate and insert?

Answer 4

Originate: Surface of the first 8 ribs
Inserts: Along the anterior medial border of the scapula

Question 5

What innervates the serratus anterior muscle?

Answer 5

The long thoracic nerve

Question 6

What is the function of the serratus anterior muscle?

Answer 6

Pulls the scapula forwards towards the ribcage - protrusion

Often called the boxers muscle as it pulls the scapula forwards when someone throws a punch

Question 7

Where does the deltoid muscle originate and insert?

Clue: originates from 3 places

Answer 7

Originate: from the spine of the scapula, acromium and lateral third of the clavicle
Inserts: deltoid tuberosity of the humerus (triangular area on front surface of middle of humerus)

Question 8

What innervates the deltoid muscle?

Answer 8

The axillary nerve

Question 9

What is the function of the deltoid muscle?

Answer 9

Abduction of the arm

Question 10

Where does pectoralis major originate and insert?

Note: two origins (one for the sternal head and one for the clavicular head - with sternal head having 3 origins)

Answer 10

Originate
Clavicular: anterior surface of medial clavicle
Sternal: anterior surface of sternum, superior six costal cartilages and aponeurosis of the external oblique muscles

Insert: intertubercular sulcus of the humerus

Question 11

What innervates the pectoralis major?

Answer 11

The lateral and medial pectoral nerves

Question 12

What are the 4 functions of the pectoralis major?

Answer 12

1. Adducts upper limb
2. Medially rotates upper limb
3. Draws scapula anterioinferiorly
4. Clavicular head of pectoralis major flexes upper limb

Question 13

Where does the pectoralis minor originate and insert?

Answer 13

Originate: from the 3-5th rib
Inserts: coracoid process of the scapula

Question 14

What innervates the pectoralis minor?

Answer 14

The medial pectoral nerve

Question 15

What is the function of the pectoralis minor?

Answer 15

Stabilises the scapula by drawing it anterioinferiorly against the thoracic wall

Question 16

Where does the long head of triceps originate and insert?

Answer 16

Originate = infraglenoid tubercle of scapula 
Insert = olecranon process of ulna

Question 17

What innervates the long head of the triceps?

Answer 17

Radial nerve C6-C8

Question 18

Where do all triceps heads insert?

Answer 18

The olecranon process of the ulna