Table 2 Features on exam to distinguish FTSDma from mimics

• Normal neurologic exam away from the instrument (i.e. no evidence of focal peripheral weakness, sensory deficit, reflex asymmetry)

• Immediate occurrence of dystonic signs with playing

• Dystonic movements are worse with specific techniques (musical passages such as scales vs. octaves, certain keys worse than others, ascending vs. descending passages)

• Constancy of the pattern of involuntary movements over time; each time the patient plays, the dystonic pattern looks similar

• Presence of a sensory geste

• Presence of mirror dystonia

• If dystonia is present in other hand tasks or at rest, the dystonia triggered by playing the instrument is usually more severe