Myotomes of the upper limb (English)

Multiple myotomes are responsible for generating most movements in the upper limb. Abduction, flexion and external rotation of the arm at the glenohumeral (shoulder) joint is controlled mainly by C5, while C6, C7 and C8 are mainly responsible for adduction and internal rotation at this joint. Flexion of the forearm at the elbow joint is controlled predominantly by C6, while C7 is the primary myotome that controls extension of the forearm at the elbow joint. Extension of the arm at the glenohumeral joint and flexion and extension at the wrist joint are mainly by C6 and C7 respectively while flexion and extension of the fingers is controlled predominantly by C7 and C8. In the hand, T1 is the single myotome involved in abduction and adduction of the index, middle, and ring fingers. Supination is by C6, while pronation is by C7 and C8 myotomes.