Unilateral pallidotomy for Parkinson's disease promptly improves a wide range of voluntary activities--especially gait and trunk movements.

26 patients with Parkinson's disease were assessed in the OFF state 2-3 days before and one week after pallidotomy for the time to complete each of 25 standardized motor tasks testing a wide range of voluntary activities important for daily living. After pallidotomy there were substantial improvements across this wide range of activities. Patients completed tasks that they could not perform preoperatively. In general for individual tasks (a) preoperative and postoperative scores were directly related, and (b) the absolute improvement (preop time-postop time) was directly related to preoperative performance: numerical improvements were greater in patients who were worse preoperatively. When the 25 tasks were ranked according to improvement relative to preoperative performance postoperative improvements were successively greater for (a) limbs ipsilateral to pallidotomy, (b) contralateral limbs, and (c) standing and walking. The best results were for activities in which the trunk plays a large part.