Use of Noncontact Low-Frequency Ultrasound in the Treatment of Chronic Foot and Leg Ulcerations

Abstract

A feasibility study was conducted to characterize the effects of noncontact low-frequency ultrasound therapy for chronic, recalcitrant lower-leg and foot ulcerations. The study was an open-label, nonrandomized, baseline-controlled clinical case series. Patients were initially treated with the Mayo Clinic standard of care before the addition of or the switch to noncontact low-frequency ultrasound therapy. We analyzed the medical records of 51 patients (median +/- SD age, 72 +/- 15 years) with one or more of the following conditions: diabetes mellitus, neuropathy, limb ischemia, chronic renal insufficiency, venous disease, and inflammatory connective tissue disease. All of the patients had lower-extremity ulcers, 20% had a history of amputation, and 65% had diabetes. Of all the wounds, 63% had a multifactorial etiology, and 65% had associated transcutaneous oximetry levels below 30 mm Hg. The mean +/- SD treatment time of wounds during the baseline standard of care control period versus the noncontact low-frequency ultrasound therapy period was 9.8 +/- 5.5 weeks versus 5.5 +/- 2.8 weeks (P < .0001). Initial and end measurements were recorded, and percent volume reduction of the wound was calculated. The mean +/- SD percent volume reduction in the baseline standard of care control period versus the noncontact low-frequency ultrasound therapy period was 37.3% +/- 18.6% versus 94.9% +/- 9.8% (P < .0001). Using noncontact low-frequency ultrasound improved the rate of healing and closure in recalcitrant lower-extremity ulcerations.