Proprioceptive feedback enhancement induced by vibratory stimulation in complex regional pain syndrome type I: an open comparative pilot study in 11 patients.

OBJECTIVE

Complex regional pain syndrome type I (CRPS-I) is now considered as a central nervous system disease with peripheral manifestations. CRPS-I may result from a mismatch between sensory input and motor output leading to a disorganization of motor programming in cortical structures. According to previous studies in the field of motor control, one efficient way to correct this mismatch could be a proprioceptive feedback enhancement. The goal of the present study was to determine whether vibratory stimulation by improving proprioceptive feedback may increase range of motion and minimize pain in patients with CRPS-I.

METHODS

An open non-randomized study was conducted in 11 patients with CRPS-I of the hand and wrist. Conventional rehabilitation sessions were given for 10 weeks. During each session, patients in the intervention group (n=7) received vibratory stimulation of the affected region; the remaining 4 patients served as the controls.

RESULTS

After 10 weeks, range-of-motion gains were about 30% larger and pain severity was about 50% lower in the intervention group than in the control group. A significant decrease in analgesic use occurred in the intervention group.

DISCUSSION: Vibratory stimulation may significantly improve range of motion and pain in patients with CRPS-I, probably by reestablishing consonance between sensory input and motor output at cortical level. Prospective randomized studies in larger numbers of patients are needed. Cross-over designs or simulated vibratory stimulation should be used to minimize bias.