RESUMO
INTRODUCTION: A patient with type 2 spino cerebellar ataxia has difficulty in carrying out alternate movements such as pronation and supination. OBJECTIVES. To evaluate the function of an automatized system for measuring disorders of alternate movements. PATIENTS AND METHODS: We studied the measurement of diadochokinesia in two groups of healthy patients, a first group (64 persons) to determine the normal intervals and a second group to validate the test (52 persons). We also studied 100 patients for validation of the system. A further 53 patients were evaluated before and after rehabilitation. RESULTS: Analysis of the basic measurements for diagnosis of duodochokinesia showed that the higher the cut off point, the greater the sensitivity of the test, whereas the opposite occurred with the specificity. Thus, regarding a higher cut off, there is a five times greater probability of a positive results in the patients than in healthy persons. However, the probability of a normal result is six times higher in healthy than in affected persons. The results of variant analysis done on patients before and after rehabilitation suggest that the presence of quantitative changes in the second study was due to the positive effect of neuro rehabilitation. CONCLUSION: The technique used is effective for differentiation of affected from healthy persons and its use is justified in the evaluation of co ordination ability after rehabilitation