Syringomyelia presenting as paroxysmal arm posturing resembling seizures.

A 9-year-old female presented with daily episodes of medically refractory paroxysmal bilateral arm posturing, which had long been thought to be epileptic seizures. She also had other types of episodes, including daily staring spells and infrequent generalized tonic-clonic convulsions. Neurologic examination was normal except for delayed cognitive development. The results of previous electroencephalograms (EEG) were normal, and magnetic resonance imaging of the head revealed a Chiari I malformation. Video EEG monitoring revealed no EEG changes during the attacks, and magnetic resonance imaging of the spine revealed a large cervical syrinx associated with the Chiari malformation. The episodes of paroxysmal bilateral dystonic arm posturing resolved after surgical intervention for the syrinx. This report illustrates that cervical cord disease is an unusual although potentially treatable condition to be considered in the differential diagnosis of paroxysmal episodes with dystonic movements of the arms, even in the absence of other physical findings of myelopathy.