The limits of stability in patients with Ménière's disease.

OBJECTIVE: To determine the ability of patients with unilateral Ménière's disease (MD) to reach the corresponding limits of stability and to define the existence of directional constraints. PATIENTS: 112 patients with unilateral MD and 30 normal age-matched subjects with no history of equilibrium problems. METHODS: A computerized dynamic posturography system was used to test the ability of subjects to displace their centre of pressure (COP) to the corresponding limits of stability. The eight targets used were separated by 45 degrees to form a circle around the subject who had to displace their COP to the target. Reaction time, velocity, accuracy and an overall evaluation of the intended movement towards and away from the target were analysed. Other characteristics of the patients were also assessed. RESULTS: A small but significant correlation was found between auditory and vestibular deficit and the different variables studied in the limits of stability test. Three factors were derived from variables obtained with short displacements, and the results are significantly different between patients and controls and are correlated with the period since the last vertigo spell, the level of disability, hearing loss and vestibular deficit. CONCLUSIONS: Dynamic balance is moderately impaired in patients with Ménière's disease. [ABSTRACT FROM AUTHOR]