Effects of transcutaneous nerve stimulation on the microcirculation in chronic leg ulcers

The purpose of this study was to find out to what extent transcutaneous electrical nerve stimulation (TENS) affects the blood flow in and around chronic lower leg ulcers, as measured with a new technique, laser Doppler imaging (LDI). Fifteen patients, mean age 73 years (range 38-85) with chronic leg ulcers of various causes participated in the study. The duration of the ulcers ranged from 3 months to 16 years. Low-frequency (2 Hz; 10-45 mA) TENS was given for 60 minutes. The changes in blood flow were measured every 5 minutes by LDI. After 60 minutes, mean blood flow had increased in the ulcer by 35%, and in the intact skin surrounding the ulcer by 15%. Even 15 minutes after the TENS had finished there was still a mean blood flow increase of 29% in the ulcer and 9% in the skin. The present results show that TENS has a stimulating effect on local blood circulation in and around chronic ulcers.