Introduction: Implementation of quantitative techniques to study disorders of coordination of movements in hereditary ataxias permits an objective description of the disease.
Objectives: To make an objective evaluation of the main disorders of coordination in patients with ataxia and compare healthy persons with those affected.
Patients and methods: We made a prospective transverse study of 43 normal persons and 50 patients with type 2 spinocerebellar ataxia (SCA2). In all cases we made a qualitative examination of Romberg's sign in two stages to increase the sensitivity. We observed how long the person could keep his balance or whether he swayed and fell. The finger-nose test and diadochokinesia were also quantitatively analyzed using a specially designed system connected to a computer which permitted quantitative analysis.
Results: We showed that the patients with SCA2 swayed when standing upright. However, they swayed and fell more when the test became more sensitive. This showed loss of postural sense. The maximum variables of the period and standard deviation were increased, whilst the effectiveness was significantly reduced in the group of patients (finger-nose test). Quantitative examination of diadochokinesia showed increased values for the maximum period, standard deviation and integral.
Conclusions: The techniques developed allow measurement of the main disorders of coordination in patients with SCA2, help to differentiate affected persons from healthy ones and are useful for the detection of moderate changes in severity during progression of the disorder.