MSK Session 3- The Arm And Cubital Fossa

Question 0

What are the proximal attachments of the heads of the biceps?

Answer 0

• long head- attaches at the supraglenoid tubercle of the scapula.
• short head- attaches to the coracoid process

Question 1

What are the three anterior arm muscles and what is their primary function?

Answer 1

Biceps brachii, brachialis, coracobrachialis

Flexion

Question 2

What are the 2 action of the biceps?

Answer 2

• flexion of the forearm at the elbow

- supination of the flexed forearm

Question 3

What is the innervation of the biceps brachii?

Answer 3

Musculocutaneous nerve (C5,6,7)

Question 4

What are the proximal and distal attachments of the brachialis?

Answer 4

• proximal- distal half of the humerus

- distal- coronoid process and ulna tuberosity.

Question 5

What is the action of the brachialis muscle?

Answer 5

Flexion of the forearm at the elbow, at all positions

Question 6

What is the innervation of the brachialis?

Answer 6

Musculocutaneous nerve (C5,6,7)

Question 7

What is the proximal and distal attachments of coracobrachialis?

Answer 7

• proximal- coracoid process

- distal- middle third of the medial humerus

Question 8

What are the two main functions of coracobrachialis?

Answer 8

-flexion and adduction of the arm

Question 9

What is the innervation of the coracobrachialis?

Answer 9

Musculocutaneous nerve (C5,6,7)

Question 10

What are the two posterior arm muscles and what is their innervation?

Answer 10

Triceps brachii and anconeus

Radial nerve

Question 11

What is the action of triceps? (2)

Answer 11

Extension of the forearm at the elbow joint

Steadies the head of the humerus during abduction

Question 12

What is the action of anconeus? (2)

Answer 12

Aids the triceps during extension

Abducts the ulna during pronation

Question 13

What is the main artery supplying the arm?

Answer 13

Brachial artery

Question 14

When does the axillary artery becomes the brachial artery?

Answer 14

Once it has passed the inferior border of teres major.

Question 15

What are the three branches of the brachial artery and when do they arise?

Answer 15

• radial and ulnar arteries arise in the apex of the cubital fossa
• profunda brachii artery arises at the inferior border of teres major and lies with the radial nerve in the radial groove of the humerus.

Question 16

List the progression of veins (distal to proximal)

Answer 16

Median antebrachial vein
Median cubital vein
Basilic and cephalic veins
Axillary vein

Question 17

What are the 5 borders of the cubital fossa?

Answer 17

Superior- imaginary line between the medial and lateral epicondyle
Medial- pronator teres
Lateral- Brachioradialis
Roof- skin, fascia and bicipital aponeurosis
Floor- brachialis and supinator

Question 18

What are the contents of the cubital fossa from lateral to medial?

Answer 18

Bicipital tendon
Brachial artery
Median nerve

Question 19

What is strange about Brachioradialis?

Answer 19

It is a flexor of the forearm at the elbow, but is innervated by the radial nerve.