The cumulative vibratory index and recovery curve parameters of the soleus H-reflex in dystonia and spasticity: a discriminant analysis

Soleus H-reflex studies were carried out in a control group consisting of 43 healthy individuals, 22 patients with upper motoneuron lesions having spasticity, and six patients with dystonia. H-M recruitment curves with and without vibration of the Achilles tendon as well as H-reflex recovery curves at H-max and half H-max intensity were determined. From the experimental data several variables were derived, such as the cumulative vibratory index and the local maxima and minima of the recovery curves. To assess the collective values of several features, a discriminant analysis was performed. The methods presented improve the specificity of the quantitative neurophysiological measure of dystonia and spasticity