Current suspected in stimulating healing
Researchers have known for some time that a measurable amount of electrical current is produced at the site of acute and chronic soft-tissue injury, explains Patricia Mertz, professor of dermatology in the Department of Dermatology and Cutaneous Surgery at the University of Miami, who has conducted an extensive review of electrical stimulation (ES) research. The current is suspected of playing a role in healing. As long as the wound remains moist, the current remains "turned on."
One theory as to why ES might aid healing asserts that the therapy reintroduces the electrical current that helps cells mobilize in chronic wounds. There is also compelling evidence showing that certain types of cells pivotal to wound healing, such as epidermal cells and cells containing growth factor, are activated by a pulsed electrical current. "This has been shown in vitro, but not in vivo," Mertz adds.
In one study Mertz reviewed, eight pressure ulcers were treated with a high-voltage pulsed current, while nine ulcers were used as controls. The electrical stimulation appeared to be an effective adjunctive therapy, but the investigators could not precisely identify the physiological mechanisms at work.
In her investigations Mertz noted that, unfortunately, clinical studies of electrical stimulation have been inconsistent, making the purely scientific case for the therapy weak.
"Each one of the papers I reviewed used a different treatment regimen, and each one used a different delivery system," Mertz explains.
"Some researchers used one type of dressing; some used another type. There was not standard protocol. Everyone is talking about something else and saying this works.’ But there hasn’t been a definitive study yet conducted on electrical stimulation and soft tissue," Mertz adds.