Efficacy and Safety of Low-Frequency,Noncontact Airborne Ultrasound Therapy (Glybetac) For Neuropathic Diabetic Foot Ulcers: A Randomized,Double-Blind,Sham-Control Study

The diabetic foot ulcer (DFU) healing rates remain dismally low. Therefore, many adjunctive therapies have been evaluated including ultrasound therapy. The prior studies with noncontact, low-frequency ultrasound were retrospective, single arm, unblinded, or with historical controls. The aim of the present study was to compare the efficacy of noncontact, low-frequency airborne ultrasound (Glybetac) therapy with sham therapy added to standard treatment in patients with neuropathic, clinically infected, or noninfected DFU (wound size >2 cm²), Wagner grades 2 and 3. Patients received ultrasound or sham therapy for 28 days dosed daily for first 6 days followed by twice a week for next 3 weeks along with standard of care. The primary outcome was percentage of patients with at least >50% decrease in wound area at 4 week of intervention. Fifty-eight patients completed the study protocol. The duration of wound was 15.8 ± 11.2 weeks and 12.1 ± 10.9 weeks and wound area of 11.3 ± 8.2 cm² and 14.8 ± 13.8 cm² (P = .507) in the ultrasound and sham groups, respectively. A >50% reduction in wound area was observed in 97.1% and 73.1% subjects (P = .042) in ultrasound and sham groups, respectively. Wound contraction was faster in the first 2 weeks with ultrasound therapy, 5.3 cm², compared with 3.0 cm² (P = .025) with sham treatment. Overall, wound area reduction of 69.4 ± 23.2% and 59.6 ± 24.9% (P = .126) was observed at 4 weeks in the ultrasound and sham groups, respectively. We conclude that the airborne low-frequency ultrasound therapy improves and hastens the healing of chronic neuropathic DFU when combined with standard wound care.