The key to diagnosing movement disorders is establishing the phenomenology of the clinical syndromeThe phenomenology is determined from the specific combination of the dominant movement disorder, the presence of any additional abnormal movements, and any further neurological or non-neurological abnormalitiesA range of conditions, both neurological and non-neurological, can mimic various movement disorders, and it is vital not to miss these lookalikesA systematic approach is recommended when clinicians see patients who present with one or more types of movement disorder
Movement disorders, such as Parkinson disease (PD), tremor, tics and dystonia, are common conditions. The overall prevalence of PD, for example, is 1% in people aged 65–85 years, increasing to 4.3% above the age of 85 years.1 The prevalence of essential tremor—the most common form of tremor—is 4% in people aged over 40 years, increasing to 14% in people over 65 years of age.2,3 The prevalence of tics in school-age children and adolescents can be as high as 21%.4
The clinical presentation of movement disorders is complex, often variable, and sometimes even bizarre. Establishing the correct diagnosis can, therefore, be difficult, even in the hands of experienced movement disorder specialists. However, accurate recognition based on clinical acumen is important for several reasons.
