Efficacy of pulsed low-intensity ultrasound in wound healing: a single-case design

Therapeutic ultrasound is used clinically to enhance healing of pressure ulcers. Limited clinical research is available and no consensus exists regarding the efficacy of ultrasound for treating pressure ulcers, particularly full-thickness pressure ulcers, in the elderly. To assess the efficacy of pulsed low-intensity ultrasound on wound healing, a double-blind, single-case, baseline-AB study was conducted. The participant, a patient in a skilled nursing facility, was a 75-year-old woman with a Stage III pressure ulcer over the coccyx. Pulsed low-intensity ultrasound was compared to placebo ultrasound. After the 1-week baseline period, each ultrasound treatment was administered 5 days a week for two consecutive weeks. Throughout the baseline and ultrasound treatment periods, the patient additionally received the standard wound care treatment program at the facility. The rate of wound surface area reduction was used as the measure of wound healing. Healing was significantly faster (P = 0.001) during the pulsed low-intensity ultrasound period (34.0 mm2/day) compared to the placebo ultrasound period (12.6 mm2/day), but was significantly faster (P = 0.001) during the baseline period (50.8 mm2/day) compared to the pulsed low-intensity ultrasound period. Healing in this patient was faster than rates noted in the literature under similar conditions. The precise effect of either ultrasound intervention in this study could not be determined. Neither pulsed low-intensity ultrasound nor placebo ultrasound likely had an appreciable effect on healing of this patient's pressure ulcer beyond that of the standard-care protocol.