About dystonia Types of dystonia Who does it affect? Focal hand dystonia can affect any profession which requires repeated hand movement but is more common among musicians than any other professional group. It is estimated that they affect approximately 1-2% of all professional musicians. Men are more commonly affected by musician’s dystonia than women with estimates of the ratio ranging from 2:1 to 6:1. Research has identified musicians who have intensively practiced their instruments over several years are most affected by this condition. Usually musician’s dystonia is diagnosed when the person is in their 20s-40s. Dystonic writer’s cramp more commonly affects those with whole body dystonia.