GAINESVILLE, Fla.---Leslie McClellan, 68, could barely hold an empty soft drink can with his left hand years after a stroke rendered his left side almost completely useless. Forget about picking up a piece of paper or grasping a pencil - or, worse yet, preparing meals.
Now he can anchor a piece of steak with a fork to cut it and once again clutch an apple.
The turnabout came after McClellan participated in a University of Florida study that used a slight electrical current to painlessly stimulate the muscles of his arm. He was one of several who regained some use of their affected fingers, hand and arm after undergoing the therapy, among the experimental rehabilitation techniques scientists say could revolutionize the way patients are treated in the months and years after a stroke, a leading cause of motor disability.
Every 53 seconds, someone in the United States has a stroke; about 600,000 Americans will suffer one this year.
Known as electromyography-triggered neuromuscular electrical stimulation, the approach is thought to retrain the brain to control voluntary movements, which often are impeded by a stroke, said James Cauraugh, an associate professor of exercise and sport sciences in UF's College of Health and Human Performance.
"It's important to work on the wrist and fingers because often they are in a state of flexion; that's when the fingers, the wrist and the elbow are all curled up close to the body," Cauraugh said. "Patients have the tendency to only grab things, rather than to extend their fingers, which often want to stay in a fist. They aren't able to activate the control, to turn on the muscles to extend those fingers."
So Cauraugh and colleagues from UF's College of Health Professions - including physical therapists Kathye Light and Andrea Behrman - set out to determine whether a small electrical stimulus could activate arm muscles to perform their usual tasks. The findings from their study of 11 patients are published in the June issue of Stroke: Journal of the American Heart Association.
Participants, who ranged in age from 43 to 78 years old, were recruited from local stroke support groups. Seven were randomly assigned to receive the electrical stimulation during 12 sessions scheduled over a two-week period. Four others comprised a control group; they attempted to complete wrist and finger extension exercises without external assistance.
"These patients weren't able to use their affected limb for any instrumental movements, such as holding up a newspaper, turning the pages of a book, drinking out of a glass or using a utensil such as a knife or fork," Cauraugh said. "Some of the people, if their left arm was affected and they wanted to place their left arm on the table, would take their right arm, grab their left arm and set it up on the table. Others would struggle to put it up there.
"Wrist and finger extension control are some of the most difficult motions to regain after a stroke," he said. "There is a dramatic spontaneous recovery of some motor capabilities for many people in the first six months to a year, but typically after a year these people remain in a dysfunctional state where they aren't able to move their affected arm."
Study participants performed various tasks designed to test their dexterity and their ability to manipulate objects before and after the treatment sessions. These included repeatedly grasping wooden blocks with the affected hand, transporting them one at a time to the other side of a box and releasing them.
During treatment, researchers placed small electrodes on the participants' forearms. The electrodes were attached to a device that monitored muscles' electrical activity as a patient tried to extend the wrist or fingers, then fired a small impulse to the muscles to help the patient complete the motion. The stimulus was not painful and was described as "slight pinpricks" or a "tickling" sensation. As patients gained muscle control, the unit automatically decreased the level of stimulation, continually challenging them to exert more control on their own.
After they completed the 12 sessions, the people who received electrical stimulation had gained upper limb control, on average doubling the number of blocks they could move in a minute, although they still could not move as many as senior citizens who were not impaired. They also performed better on a test of how much force they exerted when pushing up on a small wooden platform with their wrist, exerting more force and holding it for longer. In contrast, members of the control group did not show significant improvement.
The nature of the lesion in the brain that caused the stroke can be so severe that the signals from the brain to the muscles that straighten the elbow and raise the wrist and fingers are profoundly impaired or inhibited, said Dr. Steven Wolf, professor and director of the clinical program in restorative neurology at Emory University School of Medicine.
"The idea is if they can generate the slightest of muscle activity, the EMG-triggered electrical stimulation can then try to help those muscles that are weak contract, so those that are hyperactive -- the ones that bend the elbow, wrist and fingers -- don't simply take over, making it harder for patients to use their arms at all and leading to more pain and discomfort," Wolf said.
Cauraugh speculates the electrical impulses may help reactivate the blocked communication pathway between the brain and the wrist or finger muscles, or encourage alternate pathways to form.
"Many patients were able to move better than when they came in, and it was real dramatic for a few folks," Cauraugh said. "It opened up that avenue of 'Wow, maybe I really can do something with that limb."
Stroke survivor Leslie McClellan knows that feeling well, and the treatment seems to have helped.
"One of the first real differences I could see was eating a hamburger with my left hand while driving with my right hand. You don't realize the amount of effort it takes to hold a hamburger up to your mouth to take a bite using the hand (affected by the) stroke," McClellan said. "To be able to do that again was really a sense of accomplishment. I also can push the turn indicator for a right-hand turn much easier than before. I used to have to reach over with my right hand."
Materials provided by University Of Florida Health Science Center. Note: Content may be edited for style and length.
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