Dystonia can be a heralding symptom of Parkinson's disease (PD), but more frequently occurs as a levodopa-induced phenomenon during the course of sustained treatment. "Off" period dystonia is the most common form and mainly affects the feet; peak-dose dystonia occurs predominantly in the face/ neck, while biphasic dystonia has been observed mostly in the foot and homolateral arm/leg.14 Here we report a patient with an unusual pattern of "on"-period dystonia which gradually developed after 2 years of levodopa therapy. The dystonia involved mainly the upper extremities, was present throughout the antiparkinson effect of levodopakarbidopa (LD/CD) ("square-wave" dystonia), and had a strong action component which severely impaired arm function. The patient was studied before and after undergoing unilateral pallidotomy.
Case Report
A 49-year-old right-handed man had a 13-year history of PD, first manifested by micrographia and right leg dragging. Diagnosis was made 3 years after symptom onset and LDlCD begun with complete reversal of all symptoms. After 2 years of treatment, however, he started to experience right arm cramps, induced by vigorous arm movements while jogging. Over the years, these cramps became an inevitable companion of the antiparkinson effect of each LD/CD dose. They increased in intensity, were brought on by progressively minor movements, and spread to the left arm. Thus, the "on" state was characterized by painful and disabling dystonia in the arms. The patient preferred to be in an "off' state; however, this would leave him severely immobilized with swallowing difficulty. He ended up taking 100/25 LD/CD four to five tablets per day, leaving him "on" for approximately 6 hours per day and "off" for a total of approximately 10 hours per day. Pergolide and bromocriptine were tried but not tolerated because of lightheadedness.
On examination in the "off" state, the patient was akinetic, rigid, severely stooped, and hardly able to get up from a chair or walk unassisted. In the "on" state, bradykinesia and rigidity were significantly reduced, enabling him to get up from a chair A videotape accompanies this article.