The Brachium and Elbow Joint

Question 1

what are the 3 muscles of the anterior/flexor compartment of the ARM?

Answer 1

• Biceps Brachii
• Brachialis
• Coracobrachialis

Question 2

What is the common nerve suppy to the 3 muscles of the anterior compartment of the ARM?

Answer 2

Musculocutaneous Nerve
 (from lateral cord, has nerve roots C5, C6 and C7. supplies:
-Biceps brachii, 
-brachialis 
- coracobrachialis)

Question 3

What artery supplies the muscles of the anterior compartment of the arm? and what is its course?

Answer 3

Brachial Artery.

Brachial artery is formed from the axillary artery at the inferior border of teres major.

Initially the median nerve is lateral to the brachial artery, it quickly crosses over to lie medially to the artery.
The biceps head also lies lateral to the brachial artery
At the cubital fossa it divides into the radial and ulnar arteries which run down the forearm.

Question 4

What is the origin of Biceps Brachii?

Answer 4

Short head = Coracoid process of scapula

Long head = Supraglenoid tubercle of Scapula

Question 5

What is the insertion of Biceps Brachii?

Answer 5

Radial tuberosity

Question 6

What are the actions of Biceps Brachii?

Answer 6

• Flexor of forearm
• Supinator
• accessory flexor of arm at glenohumeral joint

Question 7

What is the origin of brachialis?

Answer 7

Anterior aspect of humerus

Question 8

What is the insertion of brachialis?

Answer 8

tuberosity of ulna

Question 9

What is the action od brachialis?

Answer 9

Flexor of forearm

Question 10

What is the origin of coracobrachialis?

Answer 10

apex of CORACOID process of scapula

Question 11

What is the action of coracobrachialis?

Answer 11

Flexor of arm at glenohumeral joint

Question 12

What is the insertion of coracobrachialis?

Answer 12

midshaft of humerus on medial side

Question 13

What is the origin of triceps brachii?

Answer 13

Long head = infraglenoid tubercle

Medial and lateral heads = posterior surface of humerus

Question 14

Where does the triceps brachii muscle insert?

Answer 14

Olecranon (of ulna)

Question 15

What is the nerve supply to the triceps?

Answer 15

Radial nerve [C5, C6, C7, C8 and T1]

Question 16

Which 2 structures run in the spiral groove of the humerus?

Answer 16

• Radial nerve (C5 - T1)

- Deep brachial artery

Question 17

What artery supplies the posterior compartment of the arm?

Answer 17

profunda brachii artery

Question 18

What muscle inserts onto the lateral lip of the inter-tubercular groove?

Answer 18

Pectoralis major inserts onto the lateral lip of the bicipital groove.