Standing postural reaction to visual and proprioceptive stimulation in chronic acquired demyelinating polyneuropathy
Clement P. Provost, Sophie Tasseel-Ponche, Pierre Lozeron, Giulia Piccinini, Victorine Quintaine, Bertrand Arnulf, Nathalie Kubis, Alain P. Yelnik
PRM Department, GH St Louis Lariboisière F. Widal, AP-HP, Paris Diderot University, 75010 Paris, France. E-mail: firstname.lastname@example.org
Objective: To investigate the weight of visual and proprioceptive inputs, measured indirectly in standing position control, in patients with chronic acquired demyelinating polyneuropathy (CADP).
Design: Prospective case study.
Subjects: Twenty-five patients with CADP and 25 healthy controls.
Methods: Posture was recorded on a double force platform. Stimulations were optokinetic (60°/s) for visual input and vibration (50 Hz) for proprioceptive input. Visual stimulation involved 4 tests (upward, downward, rightward and leftward) and proprioceptive stimulation 2 tests (triceps surae and tibialis anterior). A composite score, previously published and slightly modified, was used for the recorded postural signals from the different stimulations.
Results: Despite their sensitivity deficits, patients with CADP were more sensitive to proprioceptive stimuli than were healthy controls (mean composite score 13.9 ((standard deviation; SD) 4.8) vs 18.4 (SD 4.8), p = 0.002). As expected, they were also more sensitive to visual stimuli (mean composite score 10.5 (SD 8.7) vs 22.9 (SD 7.5), p < 0.0001).
Conclusion: These results encourage balance rehabilitation of patients with CADP, aimed at promoting the use of proprioceptive information, thereby reducing too-early development of visual compensation while proprioception is still available.
Patients with chronic acquired demyelinating polyneuropathy undergo progressive impairment of movement perception (proprioception), specially in the lower limbs, which causes balance disorders. The usual compensatory strategy by increasing the use of the visual cues is an adapted strategy when the sensory cues are really unavailable but could be counterproductive if this is not the case, then being called visual dependence. In this study, by stimulation of the visual and proprioceptive cues, patients were observed to have still a good use of proprioception despite clinical impairments. This encourages setting up rehabilitation balance programmes based on movement perception still available, fighting the visual compensation too early developed and counterproductive.