Clinical Approach
After deciding the patient has myoclonus:
explore the clinical context
determine the features of the myoclonus
consider where within the nervous system the myoclonus arises
look for associated features.
History taking should focus on age of onset, family history, precipitating events (hypoxia, toxins, medications), triggers (sensory stimulus, movement), the body parts involved and the rhythmicity of the myoclonus. Looking for associated neurological symptoms and signs (dystonia, cerebellar signs, seizures, etc) or neurological syndromes (eg, dementia) helps to select appropriate investigations, to identify underlying pathology and to optimise treatment.