Background: The purpose of the study was to investigate and follow the equilibrium performance of patients with chronic polyneuropathy using Dynamic Posturography (DP) and Randomized Perturbed Posturography (RPP).
Methods: Fourteen patients with chronic polyneuropathy, aged 53-83 years, were evaluated by clinical investigation, vibrametry, DP and RPP in a six-year follow-up. The patient group was compared to 14 healthy volunteers, aged 63-80 years. The DP comprises a sensory organization (SO) part in which the platform and visual surround are stable or referenced to the patient sway, with eyes open or closed. In a movement coordination (MC) part, the platform makes active movements. In RPP, the platform moves randomly in the anteroposterior direction.
Results: Comparison between the first and second study of the patient group showed decreased equilibrium scores under stable conditions and when vision was excluded. Compared with controls, the patients showed significantly lower scores in most of the SO test conditions except when the platform was sway referenced with stable surround; in the MC part, the patients showed prolonged muscular response latencies, and in the RPP, the patients showed increased sway areas.
Conclusions: The results are further evidence that proprioception is probably the single most important sensory input for postural control in humans. Posturography proved to be an objective method to study and follow the equilibrium performance in patients with PN.