Combined focal myoclonus and dystonia secondary to a cerebellar hemorrhage: a case report

BACKGROUND Myoclonus is a clinical sign characterized by sudden, brief jerky, shock-like involuntary movements of a muscle or group of muscles. Dystonia is defined as a syndrome of sustained muscle contractions, frequently causing twisting and repetitive movements or abnormal postures. Cases of myoclonus or dystonia secondary to a structural lesion in the cerebellum have been reported. However, there has never been a reported case of combined myoclonus and dystonia secondary to a cerebellar lesion. CASE PRESENTATION Herein, we report a 22-year-old female patient with sudden-onset myoclonic jerks, dystonic posture and mild ataxia in the right upper extremity. At age 19, she experienced sudden headache with vomiting. The neurological examination showed ataxia, myoclonus and dystonia in the right upper extremity. Brain images demonstrated a hemorrhage in the right cerebellar hemisphere secondary to a cavernous malformation. After resection of the hemorrhagic mass, headache with vomiting disappeared and ataxia improved, but myoclonus and dystonia persisted. CONCLUSIONS It is the first report of combined focal myoclonus and dystonia secondary to a cerebellar lesion.