Kinematic evaluation of gestural and repetitive single joint movements of the arm after posteroventral pallidotomy, subthalamotomy or both procedures combined in two Parkinson's disease patients: two case studies.

Two patients with severe Parkinson's disease undergoing partial or complete ablative interruption of basal ganglia (BG) output are presented. One patient who underwent bilateral subthalamotomy, and a second who underwent unilateral posteroventral pallidotomy, followed 7 years later by a bilateral subthalamotomy because of contralateral disease progression, were studied. In addition to the usual clinical evaluation, changes in joint kinematics observed during unconstrained, skilled multi-joint movement and repetitive single joint (RSJ) movement of the wrist were studied. Clinical UPDRS items referred to hand movements contralateral to the procedure, and instrumental measurement of RSJ improved in both patients after either pallidotomy or subthalamotomy. When both BG outflow paths were interrupted as was the case in the second patient (bilateral subthalamotomy after the initial pallidotomy), no added clinical improvement was observed, RSJ even deteriorated slightly. Instrument-based studies for movement alteration detection after simultaneous ablation of the globus pallidus and the subthalamic nucleus of these two patients showed greater sensitivity than clinical evaluation alone. Complex gestural movement performance remained unaffected after partial (subthalamotomy or pallidotomy) or complete interruption of BG outflow (case 2), indicating BG compensatory capacity after total outflow interruption remained intact.