Stroke survivors who have difficulty using an arm or a hand experience lasting mobility gains after completing an unusual 2-week rehabilitation program, a new study finds.
Constraint-induced movement therapy (CIMT) exercises a weakened limb repetitively while restraining the better-functioning limb with either a sling or a mitt for much of the day.
Among patients who had had strokes within the previous 3 to 9 months, 2 weeks of clinician-supervised CIMT produced more mobility in their stroke-weakened arms over the ensuing year than standard rehabilitation approaches did, reports a team led by neuroscientist Steven L. Wolf of Emory University School of Medicine in Atlanta. Wolf and his coworkers present their findings in the Nov. 1 Journal of the American Medical Association.
“CIMT should be considered as a valuable form of rehabilitation for stroke patients who have lost arm function,” Wolf says. He estimates that as many as 30 percent of stroke survivors can benefit from this intervention.
In the United States each year, about 566,000 people experience arm or hand impairments due to stroke-related brain damage. For most, these mobility difficulties last at least 3 months.
The researchers randomly assigned 222 stroke patients, recruited from seven hospitals across the country, to receive either CIMT or standard care, which ranged from no treatment to various occupational and physical therapies.
Over 2 weeks, each CIMT participant wore a mitt on his or her less-affected hand for most waking hours. On each weekday, the person received up to 6 hours of training in using the stroke-impaired hand and arm to perform basic tasks, such as writing and eating.
Wolf’s team evaluated each patient immediately after the assigned treatment, and again 4, 8, and 12 months later. During those assessments, patients performed tasks designed to measure arm and hand dexterity and described how well and how often they used their impaired limbs in daily activities. Of the initial participants, 169 completed 12-month evaluations.
Mobility in the affected arm and hand improved for both groups. However, the CIMT participants displayed substantially greater advances immediately after treatment than the standard-care group did, the scientists say. Mobility advantages for the CIMT group over the other participants increased steadily during the next year.
Study coauthor Edward Taub of the University of Alabama in Birmingham had previously directed brain-imaging studies in small groups of stroke patients and in monkeys with experimentally severed arm nerves. The findings indicated that CIMT stimulates brain reorganization that fosters arm rehabilitation. In the 1980s, animal rights activists succeeded in halting Taub’s work with monkeys.
The new investigation underscores the value of the initial monkey research, says neurologist John R. Marler of the National Institute of Neurological Disorders and Stroke in Bethesda, Md. Wolf’s study “shows that it’s possible to harness the remarkable plasticity in the brain to improve the lives of stroke patients,” Marler remarks.