Upper Limb Myotomes and nerve roots

Question 1

Describe upper limb nerve roots and function?

Answer 1

C5 - Elbow Flexion (bicep), Shoulder abduction (Deltoid), sensation over lateral antecubital fossa proximal to the elbow joint

C6 - Elbow flexion. Wrist extension. Sensation over lateral forearm and index finger.

C7 - Elbow extension, triceps, wrist flexors, sensation over middle finger

C8 - Finger flexion, ulnur deviation, sensation over little finger and medial forearm.

T1 - Finger abduction/adduction. Medial antecubital fossa.

Question 2

What is the dermatome distribution of the upper limb?

Answer 2

C5 - Lateral aspect of upper arm, proximal to the lateral epicondyle.
C6 - Lateral aspect of forearm and palmar aspect of thumb
C7 - Middle Finger
C8 - Little Finger, medial side of forearm
T1 - Medial aspect of arm, proximal medial epicondyle.

Question 3

What are effects of radiculopathies of certain nerve zones?

Answer 3

C5 Radiculopathy - Weakness with shoulder abduction and effects sensation lateral portion of arm

C6 Radiculopathy - Elbow flexion, wrist extensors, lateral forearm, thumb, index finger and hand

C7 Radiculopathy - Elbow extensors and wrist flexors, sensation over the middle finger

C8 Radiculopathy - Weakness finger flexors, sensation over the medial aspect of forearm and little finger.

T1 Radiculopathy - Weakness with finger abduction, medial aspect of the antecubital fossa/