Myoclonus is either the only or the most prominent finding in essential myoclonus. Myoclonus is therefore a nearly isolated phenomenon from which the patient usually experiences relatively mild disability. Essential myoclonus may be sporadic or genetically determined and either does not progress or progresses very slowly over many years. Hereditary essential myoclonus is characterized by onset before age 20, dominant inheritance with variable severity, a benign clinical course compatible with an active life and normal longevity, and the absence of other neurological signs. The myoclonus typically is generalized, is exacerbated by muscle activation, and is substantially decreased by alcohol ingestion. The term “myoclonus-dystonia” syndrome has been introduced because of the common occurrence of dystonia in these cases.
KeywordsPublic Health Internal Medicine Partial Response Daily Activity Muscle Activation
The patient exhibits generalized myoclonus at rest involving the trunk and lower more than upper extremities.
Essential myoclonus.mp4 (MP4 3,792KB)