Big Nerves Of Brachial Plexus

Question 1

Pathway of the musculocutaneous nerve

Answer 1

Pierces the coracobrachialis (medial to lateral) and emerges on the anterior surface
Runs between the brachialis and biceps muscle bodies
Pierces the brachial fascia to end and continues

Question 2

Muscles innervated by the musculocutaneous nerve

Answer 2

Biceps brachii
Coracobrachialis
Brachialis

Question 3

What is the musculocutaneous nerve sensory to?

Answer 3

Lateral antebrachium (lateral forearm)

Question 4

The median nerve is formed by:

Answer 4

The medial and lateral branches of the lateral and medial cords, forms anterior to the axillary artery

Question 5

Pathway of the median nerve

Answer 5

Runs on lateral surface of the brachial artery.
Crosses the brachial artery approx mid-arm to the medial side and comes in contact with the brachialis muscle
Enters the cubital fossa deep to the bicipital aponeuroses and median cubital vein

Question 6

Innervation of the muscles

Answer 6

No branches in the arm but is a major player in the forearm and hand

Question 7

Sensory of the median nerve

Answer 7

Hand- radial 2/3rds of the palm and Dortmund of the 2nd 3rd and radial half of the 4th distal to the interphalangeal joint

Question 8

Ulnar nerve is a continuation of:

Answer 8

The medial cord on the medial aspect of the axillary artery

Question 9

Pathway of the ulnar nerve

Answer 9

Runs anterior to the insertion of the teres major and long head of the triceps on the medial aspect of the axillary/brachial artery.
Accompanies the profunda brachii artery at its origin and moves medically to pierce the medial intermuscular septum with the superior ulnar collateral artery to enter the forearm between the heads of the pronator teres.

Question 10

The musculocutaneous nerve changes to:

Answer 10

Lateral Cutaneous Nerve of the Forearm- runs along the cephalic vein

Question 11

Medial brachial and medial antebrachial cutaneous nerves (sensory) originate from the:

Answer 11

Medial cord proximal to the formation of the ulnar nerve.

Can be confused for the ulnar nerve*

Question 12

Sensory of the ulnar nerve:

Answer 12

the medial surface of the arm and forearm as the sensory branch names indicate

Question 13

Radial nerve is formed by:

Answer 13

Posterior cord, posterior to the axillary artery

Question 14

Pathway of the radial nerve

Answer 14

Begins to the axillary artery, medial to the humerus, anterior to the subscapularis muscle.
Crosses the latissimus dorsi tendon to run ant to the long head of the triceps muscle.
Passes through the trangular interval formed by the long and medial heads of the triceps and the tendon of the teres major, along with the profunda brachii branch of the axillary artery (deep brachial artery)
Enters the spiral groove of the humerus with the profunda, proper to the groove it innervates the long and lateral heads of the triceps

Question 15

Where does the posterior cutaneous nerve of the arm form

Answer 15

Long head of the triceps muscle

Question 16

In the spiral groove, the radial nerve supplies:

Answer 16

Branches to the medial head of the triceps and anconeus. It also supplies sensory branches to the posterior arm and forearm

Question 17

After exiting the spiral groove, the radial nerve:

Answer 17

Pierces the lateral intermuscular septum to run between the brachialis and brachioradialis muscles to the cubital fossa

It then spilts into a deep muscular branch and a superficial sensory branch

Question 18

Muscles innervated by the radial nerve

Answer 18

Posterior compartment muscles of the arm: Triceps and anconeus

Question 19

Sensory of the radial nerve

Answer 19

Lateral dorsal of the hand and proximal 1/2 of the 2nd and 3rd digits

Question 20

Axillary nerve is formed by:

Answer 20

The posterior cord forms posterior to the axillary artery

Question 21

Pathway of axillary nerve

Answer 21

After branching from the posterior cord it passes laterally through the quadrangular space with the posterior circumflex humeral artery.

Sends a branch to the superior lateral brachium (up over the body of the deltoid muscle) as it circles the surgical neck of the humerus

Question 22

Where does the axillary nerve terminate

Answer 22

As the branches to the teres minor and deltoid with a sensory branch to the glenohumeral joint

Question 23

Muscles innervated by axillary nerve

Answer 23

Deltoid, teres minor

Question 24

Sensory of the axillary nerve

Answer 24

Lateral aspect of the superior brachium