Movement disorders are a complex group of disorders spanning all aspects of neurological illnesses and ranging from conditions characterised by too little movement (hypokinesis) to those where movement is excessive (hyperkinesis). Diagnosis is based mostly on observation and examination rather than radiology and serological assessments. The classic example would be Parkinson's disease, while other movement-related problems, such as tremor, chorea, dystonia, myoclonus, hemiballism and tics, occur in a range of inherited, drug-induced and sporadic disorders. Genetics plays an important part in t.