Action tremor, defined as postural and kinetic tremor, occurs frequently and is diagnosed as essential tremor (ET) if a bilateral, visible, and persistent action tremor affecting both upper extremities has been present for at least 3 years without other neurological signs like dystonia, parkinsonism, or ataxia.1 The most recent consensus paper on ET by the International Movement Disorders Society defines ET as a syndrome rather than an etiologically homogeneous disease.
