St. Louis, Nov. 30, 2000 — Researchers at Washington University School of Medicine in St. Louis have found that a new technique called constraint-induced movement (CIM) therapy, or forced-use therapy, allows stroke patients to improve motor functions, even if therapy does not begin until 14 days after their stroke. The results from this pilot study appear in the December issue of the journal Stroke.
Each year, roughly 730,000 Americans suffer a temporary loss of blood flow to the brain, known as an ischemic stroke. Many survivors have difficulty moving one of their arms and consequently struggle to perform normal routine activities, such as getting dressed.
Although interventions during or immediately after a stroke have improved greatly in recent years, no currently available treatments facilitate motor recovery several days, months or years after a stroke. "Millions of people who had a stroke some time ago are looking for some way to improve," says Alexander W. Dromerick, M.D., first author of the study. "Research on stroke prevention and early intervention isn’t going to help them." Dromerick is an associate professor of neurology and of occupational therapy at the School of Medicine.
Traditional rehabilitation therapies try to optimize the use of the unaffected limb. "Rehabilitation focuses on the return to independence," Dromerick explains. "The typical approach has been that we don’t care how you get dressed as long as you do it."
Such methods help compensate for stroke-induced disability but do not attempt to treat the impairment, the researchers point out. "We want you to dress independently, but we want you to do it because you have recovered strength and coordination, not because you’ve learned a trick for one-handed dressing," Dromerick says.
CIM therapy, scientists argue, helps patients regain strength and coordination. The treatment encourages use of the impaired arm as much as possible rather than promoting dependence on the healthy limb.
Dromerick and colleagues randomly placed 23 patients who had suffered an ischemic stroke within the previous 14 days into two groups: The control group received traditional occupational therapy that focused on compensatory techniques. The other group received CIM therapy that focused on the affected arm. In between sessions, the CIM patients wore a padded mitten on the healthy hand for at least six hours per day. The mitten discouraged them from using this hand. Both groups had therapy for two hours a day, five days per week, for 14 days.
Twenty of the 23 patients completed treatment. One patient in the CIM group recovered sufficiently to be discharged before the end of the 14 days. Two patients in the traditional therapy group failed to complete treatment because one died and one had a second stroke. No patient withdrew because of pain or frustration.
At the end of these 14 days of therapy, the CIM patients showed more improvement in overall arm strength and coordination than patients who received traditional therapy. They were particularly improved at pinching tasks, such as those critical to buttoning a shirt or picking up a fork. In some functional tasks, like getting dressed, they did better. "People who received the experimental treatment were certainly as independent as the other patients, and there were some indications that the group as a whole was more independent," says Dromerick.
He and his colleagues hope to study a larger patient group to investigate this effect further and to find out how long the positive effects last. Using imaging techniques, they will examine the effects of treatment on stroke-related brain lesions. To evaluate motor recovery, they will use kinematic assessment techniques. Although others have detected changes in the brain after forced-use therapy, it is not known whether these changes result from routine clinical care or from this particular treatment.
"This study suggests that there’s another therapeutic window for stroke patients," says Dromerick. "It’s becoming clear that the activities a person engages in can affect recovery and that those interventions can impact the person’s ability to perform their normal social roles." He and his colleagues are eager to see how these interventions translate into structural changes in the brain.
Dromerick AW, Edwards DF, Hahn M. Does the application of constraint-induced movement therapy during acute rehabilitation reduce arm impairment after ischemic stroke? Stroke, 31. December, 2000.
Funding from The American Heart Association and The McDonnell Foundation.
The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC Health System.