Crossed Choreoathetosis Caused by Unilateral Thalamic Hemorrhage.

In general, involuntary movements after stroke are due to a disturbance in the unilateral cortico-basal ganglia loop and appear contralateral to stroke lesions. Crossed involuntary movements after unilateral stroke are very rare. We observed a case of crossed involuntary movements in the left upper limb and right lower limb after a right thalamic hemorrhage expanded to the right subthalamic nucleus. We considered a possible three-step theory as the basis of crossed choreoathetosis. This case informs our better understanding of the cortico-basal ganglia loop and involuntary movements after stroke.