Skin sympathetic function in complex regional pain syndrome type 1.

ABSTRACT

PURPOSE: Cutaneous sympathetic pathophysiology in complex regional pain syndrome type 1 (CRPS-1) is not yet completely understood. To evaluate cutaneous sympathetic dysfunction in CRPS-1, we evaluated sympathetic sweat response (SSwR) and skin vasomotor reflex (SkVR) in CRPS-1 patients. METHODS: We studied 10 CRPS-1 patients (age 41 ± 13 years; 5 females and 5 males; disease duration 20 ± 22 months) and 10 healthy subjects (age 44 ± 13 years; 3 females and 7 males). SkVRs and SSwRs to several sympathetic activating procedures were recorded on the palms of the CRPS-1 patients (affected side) and controls (right side). RESULTS: There were no significant differences in the baselines of sweat output and skin blood flow between the CRPS-1 and control groups. SSwR and SkVR amplitudes were significantly lower in the CRPS-1 group than in the control group. There was no significant correlation between disease duration and SSwR or SkVR amplitudes among the patients. CONCLUSIONS: The reduced SSwRs and SkVRs in the affected limb of our CRPS-1 patients may reflect underlying damage to the sympathetic postganglionic fibres.