Background: One of the most disabling manifestations of adult extrapyramidal disorders is gait impairment. In Parkinson's disease (PD) it can be characterised by freezing episodes. They usually appear late in the course of the disease and their pathogenetic mechanism is obscure. Objective: To determine the neurochemical basis of gait disorders and free/ing phenomena, an apomorphine test was carried out. Methods: Fifteen patients with Parkinson's disease complicated by freezing phenomena and seven patients with progressive supranuclear palsy (PSP) with gait disturbance consented to participate in this study. The patients were assessed by Hoehn & Yahr, UPDRS and PSPRS scales. Before and after 12'. 25'. 60', 120' and 180' administering an apomorphine bolus (30 mcgr/kg), patients were assessed with a gait scale designed to measure the time spent in a 12-m walk. The walk consisted of starting to walk, walking, turning and coming back to the sitting position (walking test). The test was considered positive il a reduction of > 20% in walking time was recorded, doubtful if the reduction was between 10% and 20%. negative if the reduction was <10%. The improvement in the parkinsonian signs after each apomorphine bolus was assessed by the motor section of the UPDRS. Results: Eleven out of fifteen patients with PD showed a motor improvement > 20% by walking test. In four out of fifteen patients the walking test was doubtful. In the group of patients with PSP the walking test was positive in two out of seven patients. The side effects observed were drowsiness and nausea, but they didn't influence the execution of the test. Conclusion: The apomorphine test positive in the majority of PD patients suggests that in this group the gait disturbance is a direct consequence of the loss of the dopaminergic innervation of the striatum, characteristic of PD, and it may be improved by higher doses of dopaminergic drugs. The lack of benefit obtained in the majority of PSP patients could indicate that in these cases symptoms were not attributable to a striatal dopamine deficiency of presynaptic origin and that the gait impairment may be the consequence of a different neurochemical deficit.
|Number of pages||1|
|Journal||Italian Journal of Neurological Sciences|
|Publication status||Published - 1999|
ASJC Scopus subject areas
- Clinical Neurology