Standing postural reaction to visual and proprioceptive stimulation in chronic acquired demyelinating polyneuropathy

To investigate the weight of visual and proprioceptive inputs, measured indirectly in standing position control, in patients with chronic acquired demyelinating polyneuropathy (CADP).

Prospective case study.

Twenty-five patients with CADP and 25 healthy controls.

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.

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).

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.