Myotomes (MA)

Question 1

What is a myotome?

Answer 1

(motor function equivalent to the dermatomes) it is a group of muscles that are innervated by a single spinal root.

Question 2

What are the myotomes associated with shoulder abduction and lateral rotation; shoulder adduction and internal rotation; shoulder flexion/extension, elbow flexion and extension

Answer 2

Shoulder abduction & lateral (external) rotation: C5
Shoulder adduction & medial (internal) rotation: C6, C7, C8
Shoulder flexion: C5
Shoulder extension: C6, C7, C8
Elbow flexion: C5 & C6
Elbow extension: C6, C7