4.2. The Radial Nerve Flashcards
What is the Radial Nerve?
A Major Peripheral Nerve in the Upper Limb
Where does the Radial Nerve arise?
In the Axilla
What is the Radial Nerve arise from?
It is a Continuation of the Posterior Cord of the Brachial Plexus
What is the Segmental (or Root) Value of the Radial Nerve?
- C5
- C6
- C7
- C8
- T1
Where is the Radial Nerve located, in relation to the Axillary Artery?
It sits Posteriorly to the Axillary Artery - in the Axilla
How does the Radial Nerve exit the Axilla?
Inferiorly, Via the Triangular Interval
What happens to the Radial Nerve after it leaves the Axilla?
It Descends down the Arm
Where does the Radial Nerve travel in the Upper Arm?
In the Radial Groove of the Humeus
What happens to the Radius as it travels down, next to the Humerus?
It Laterally Wraps around the Humerus
What is the Radial Nerve accompanied by for most of its course of the Upper Arm?
The Deep Branch of the Brachial Artery
How does the Radial Nerve enter the Forearm?
It moves Anteriorly, Over the Lateral Epicondyle of the Humerus, through the Cubital Fossa
What happens to the Radial Nerve, as it passes through the Cubital Fossa?
It Terminates, dividing into 2 Nerves
What are the 2 Nerves which the Radial Nerve divides into, in the Cubital Fossa?
- Deep Branch of the Radial Nerve
2. Superficial Branch of the Radial Nerve
Where does the Radial Nerve innervate Muscles?
- Posterior Upper Arm
2. Posterior Compartment of the Forearm
What does the Radial Nerve innervate in the Posterior Upper Arm?
The 3 Heads of the Triceps Brachii
What is the Action of the Triceps Brachii?
This Extends the Arm at the Elbow
What does the Radial Nerve supply as it leaves the Axilla?
- Long Head of the Triceps Brachii
2. Medial Head of the Triceps Brachii
As The Radial Nerve Laterally Wraps around the Humerus, what does it supply?
It Supplies a Branch to the Long Head of the Triceps Brachii
What Muscles of the Forearm, does the Radial Nerve Supplies Branches for?
- Brachioradialis Muscle
2. Extensor Carpi Radialis Longus
What is the Deep Branch of the Radial Nerve associated with?
Innervation of the Muscles of the Posterior Compartment of the Forearm
Where does the Radial Nerve provide Sensory innervation for?
- Upper Arm
- Forearm
- Hand
How many Sensory Branches of the Radial Nerve are there?
4
What are the 4 Sensory Branches of the Radial Nerve?
- Lower Lateral Cutaneous Nerve of the Arm
- Posterior Cutaneous Nerve of the Arm
- Posterior Cutaneous Nerve of the Forearm
- Terminal Superficial Branch of the Radial Nerve
What does the Lower Lateral Cutaneous Nerve of the Arm provide Sensory innervation for?
Lateral Aspect of the Upper Arm
