A prospective pilot study of ultrasound therapy effectiveness in refractory venous leg ulcers

Venous insufficiency is the most common cause of leg ulcers in the United States. Venous leg ulcers cost the health care system billions of dollars annually, and healing rates are less than 70% with standard of care; therefore, new therapies are needed to increase healing times and minimize associated costs. Non contact ultrasound therapy has been used to treat a variety of chronic wounds including venous leg ulcers, and it is thought that ultrasound has an effect on decreasing the bacterial count in wounds, although the exact mechanism of action of ultrasound is yet to be determined. We conducted an open labelled pilot study of 10 refractory venous ulcers of large size to determine the effect of non contact ultrasound on wound closure, bacterial counts, expression of inflammatory cytokines and pain reduction. We lacked a sham control group but we compared the baseline and end of treatment assessments and noted the differences. We found a significant reduction in wound area (P = 0·0039) over the 4-week treatment period. We also found a decline in individual and total bacterial counts; however, these differences were not significant. For all patients, there was also a trend toward reduced inflammatory cytokine expression compared with baseline levels; however, this reduction did not reach statistical significance. Interestingly, there was a correlation between healing and change in cytokine expression, which showed statistically significance for tumour necrosis factor (TNF)-αP = 0·0395, IL-1a P = 0·0351, IL-6 P = 0·0508, IL-8 P = 0·0990. Pain as measured by the visual analogue scale (VAS) was reduced from 4 at the baseline to 2·7 by the end of the study. In conclusion, we found that patients treated with ultrasound therapy and compression therapy show clinical improvement over the course of 4 weeks and had a decrease in inflammatory cytokines, bacterial counts and pain.