Tremor may be classified by two main axes1:
Axis I Clinical Features:
Reviewed in the following six subsections:
2.1.1 Activating Condition
From: Bhatia KP, Bain P, Bajaj N, et al. Consensus Statement on the classification of tremors. From the task force on tremor of the International Parkinson and Movement Disorder Society. Mov Disord. 2018;33(1):75-87.
2.1.2 Anatomic distribution
2.1.3 Frequency
2.1.4 Amplitude
2.1.5 Regularity
2.1.6 Combination with other movement disorders
Tremor can also be viewed as isolated, or combined, when present together with other movement disorders. In the case of tremor presenting in combination with other features, key abnormalities to identify include the presence of dystonia (in the affected limb or distant body part), bradykinesia, and cerebellar features with or without cognitive and/or gait impairment.
The various clinical features of tremor may be used to define a clinical syndrome.
- A clinical syndrome may have multiple aetiologies, and
- A particular aetiology may produce multiple tremor syndromes. Examples of syndromes include ET, ET plus syndrome, enhanced physiological tremor2.