<qa>  What is the pathophysiology of musicians dystonia?Though the pathophysiology of musicians dystonia has yet to be determined fully, the motor learning associated with playing a musical instrument probably results in both functional and structural changes in the brain 13. This plastic reorganization, including the rapid unmasking of existing neural circuitry and the establishment of new connections, is probably fundamental to the accomplishment of skillful playing, but also may result in focal, task-specific dystonia. When musicians get dystonia, their playing abilities can become severely compromised, to the point where they may not be able to perform professionally, and possibly not even teach. While botulinum toxin injections can be highly successful in allowing musicians to perform again, there are no objective methods to evaluate improvement. 