Hemiataxia is ataxia confined to one half of the body. The vast majority of isolated hemiataxic syndromes reflect a lesion of the ipsilateral cerebellar hemisphere, but on occasion supratentorial lesions may cause hemiataxia (posterior limb of the internal capsule, thalamus). However, in almost all of these cases hemiataxia coexists with ipsilateral hemiparesis (ataxic hemiparesis, q.v.), hemisensory disturbance (hemiataxia-hypesthesia), or both.
Luijckx G-J, Boiten J, Lodder J, Heurs-van Raak L, Wilmink J. Isolated hemiataxia after supratentorial brain infarction. Journal of Neurology,Neurosurgery and Psychiatry 1994; 57: 742-744