[Treatment of various dyskinesias by intermittent thalamic stimulation]

Abnormal movements or dyskinesias are associated with hyperpathia and hyperalgesia in a number of conditions such as post amputation jumping stumps pseudothalamic syndromes following cerebro vascular accidents and in some cases of demyelinating diseases. Intermittent electrical stimulation of the specific sensory nucleus of the thalamus (I.T.S.) controls at the same time pain and dyskinesias with the same long lasting effect. In some cases where dyskinesias are associated with sensory deafferentation, but not with chronic pain or hyperpathia, the same positive effect of thalamic stimulation on the control of abnormal movements is achieved while in other cases of tremor or dyskinesias without sensory deafferentation such as parkinsonism, intention tremor etc.. the efficacy of I.T.S. is nil. Hence, discriminative sensory deaffrentation is the common link between the cases of tremor or dyskinesias that use to respond to I.T.S. which is up to now the only therapy of proven efficacy in such conditions.