Sympathetic Skin Response at Big toe in Diabetic polyneuropathy

J Korean Assoc EMG Electrodiagn Med 2006;8(1):1-6.
Published online May 10, 2006.

Abstract

Objectives: The aim of this study was to determine whether the sympathetic skin response (SSR) recorded from the big toe is more effective than standard SSR recorded from the sole for the detection of sudomotor fiber dysfunction in diabetic neuropathy. Methods: We recorded big toe SSR (SSRBT) and plantar SSR (SSRP) in 23 diabetic patients and 30 age-matched normal controls. For SSRP, surface electrodes were attached to the sole (G1) and dorsum of foot (G2) and for SSRBT, surface electrodes were attached to the toe-tip (distal phalanx, G1) and to the dorsum of the proximal phalanx of the big toe (G2). Peak to peak SSR amplitudes were measured and the response with largest amplitudes were selected. A deep inspiration was used as stimulus. Results: With regard to controls, SSRP amplitude was not reduced. In contrast, SSRBT amplitude was reduced in patient group (p<0.0001). In 5 patients, SSRBT was not recordable while SSRP still persisted. Conclusion: Our results suggest that SSRBT is more effective test than SSRP in detecting distal sudomotor failure in patients with diabetic neuropathy.

Key Words: Sympathetic skin response, Diabetic neuropathy