Which myotome is responsible for finger abduction and adduction?

The myotome responsible for finger abduction and adduction is T1. This myotome correlates with the innervation of the intrinsic muscles of the hand, specifically the interossei muscles, which are crucial for the movements of spreading the fingers apart (abduction) and bringing them together (adduction).

In contrast, C6, C7, and C8 have different primary functions. C6 is primarily involved in wrist extension; C7 contributes to elbow extension and wrist flexion, and C8 is more associated with finger flexion rather than the specific movements of abduction and adduction. This distinction highlights the unique role that T1 plays in fine motor control of the hand, particularly regarding the spacing and gathering of fingers, which are essential for various grasping and pinching actions.