4.2. The Radial Nerve

Question 1

What is the Radial Nerve?

Answer 1

A Major Peripheral Nerve in the Upper Limb

Question 2

Where does the Radial Nerve arise?

Answer 2

In the Axilla

Question 3

What is the Radial Nerve arise from?

Answer 3

It is a Continuation of the Posterior Cord of the Brachial Plexus

Question 4

What is the Segmental (or Root) Value of the Radial Nerve?

Answer 4

1. C5
2. C6
3. C7
4. C8
5. T1

Question 5

Where is the Radial Nerve located, in relation to the Axillary Artery?

Answer 5

It sits Posteriorly to the Axillary Artery - in the Axilla

Question 6

How does the Radial Nerve exit the Axilla?

Answer 6

Inferiorly, Via the Triangular Interval

Question 7

What happens to the Radial Nerve after it leaves the Axilla?

Answer 7

It Descends down the Arm

Question 8

Where does the Radial Nerve travel in the Upper Arm?

Answer 8

In the Radial Groove of the Humeus

Question 9

What happens to the Radius as it travels down, next to the Humerus?

Answer 9

It Laterally Wraps around the Humerus

Question 10

What is the Radial Nerve accompanied by for most of its course of the Upper Arm?

Answer 10

The Deep Branch of the Brachial Artery

Question 11

How does the Radial Nerve enter the Forearm?

Answer 11

It moves Anteriorly, Over the Lateral Epicondyle of the Humerus, through the Cubital Fossa

Question 12

What happens to the Radial Nerve, as it passes through the Cubital Fossa?

Answer 12

It Terminates, dividing into 2 Nerves

Question 13

What are the 2 Nerves which the Radial Nerve divides into, in the Cubital Fossa?

Answer 13

1. Deep Branch of the Radial Nerve

2. Superficial Branch of the Radial Nerve

Question 14

Where does the Radial Nerve innervate Muscles?

Answer 14

1. Posterior Upper Arm

2. Posterior Compartment of the Forearm

Question 15

What does the Radial Nerve innervate in the Posterior Upper Arm?

Answer 15

The 3 Heads of the Triceps Brachii

Question 16

What is the Action of the Triceps Brachii?

Answer 16

This Extends the Arm at the Elbow

Question 17

What does the Radial Nerve supply as it leaves the Axilla?

Answer 17

1. Long Head of the Triceps Brachii

2. Medial Head of the Triceps Brachii

Question 18

As The Radial Nerve Laterally Wraps around the Humerus, what does it supply?

Answer 18

It Supplies a Branch to the Long Head of the Triceps Brachii

Question 19

What Muscles of the Forearm, does the Radial Nerve Supplies Branches for?

Answer 19

1. Brachioradialis Muscle

2. Extensor Carpi Radialis Longus

Question 20

What is the Deep Branch of the Radial Nerve associated with?

Answer 20

Innervation of the Muscles of the Posterior Compartment of the Forearm

Question 21

Where does the Radial Nerve provide Sensory innervation for?

Answer 21

1. Upper Arm
2. Forearm
3. Hand

Question 22

How many Sensory Branches of the Radial Nerve are there?

Answer 22

4

Question 23

What are the 4 Sensory Branches of the Radial Nerve?

Answer 23

1. Lower Lateral Cutaneous Nerve of the Arm
2. Posterior Cutaneous Nerve of the Arm
3. Posterior Cutaneous Nerve of the Forearm
4. Terminal Superficial Branch of the Radial Nerve

Question 24

What does the Lower Lateral Cutaneous Nerve of the Arm provide Sensory innervation for?

Answer 24

Lateral Aspect of the Upper Arm

Question 25

What does the Posterior Cutaneous Nerve of the Arm provide Sensory innervation for?

Answer 25

Posterior Surface of the Upper Arm

Question 26

What does the Posterior Cutaneous Nerve of the Forearm provide Sensory innervation for?

Answer 26

Strip of Skin down the Middle of the Posterior Forearm

Question 27

What is the Significance of the Superficial Branch of the Radial Nerve?

Answer 27

It is the Terminal Division of the Radial Nerve

Question 28

What does the Superficial Branch of the Radial Nerve provide Sensory innervation for?

Answer 28

Dorsal Surface of the Lateral 3 1/2 Digits, and their associated Palm Area