In the largest, most comprehensive study of its kind to date, researchers supported by the National Institutes of Health (NIH) showed clinical improvements out to one year when stroke survivors who had lost function in one arm were given a unique, two-week rehabilitation regimen.
Steven Wolf, Ph.D., Professor of Rehabilitation Medicine at Emory University, led a multi-center team that tested the effects of constraint-induced movement therapy (CIMT) in 222 patients. The study, which is featured in the November 1, 2006 issue of The Journal of the American Medical Association,* was funded by the National Institute of Child Health and Human Development (NICHD) and the National Institute of Neurological Disorders and Stroke (NINDS).
"This study provides the strongest evidence to date that constraint induced movement therapy can help stroke patients regain lost arm function," said NIH Director Elias A. Zerhouni, M.D. "This is welcome news for stroke patients and those who care about them."
Each year, more than 700,000 Americans are hospitalized for stroke, an interruption of blood flow in the brain. Up to 85 percent of survivors have weakness on one side of their body.
CIMT involves training the weakened hand and arm through repetitive exercises, while restraining the unaffected hand and arm with a mitt like a boxing glove. The theory behind the hand restraint is that it forces the wearer to use the affected hand and arm.
"We now have an intervention that is beneficial for between 5 and 30 percent of the stroke population. CIMT should be considered as a valuable form of rehabilitation, and opens the door to further explorations," said Dr. Wolf.
Known as the EXCITE trial, for Extremity Constraint Induced Therapy Evaluation, Dr. Wolf's study involved people who had weakness in one arm caused by a stroke within the prior three to nine months. About half of the trial participants received customary care, ranging from no treatment to standard physical therapy, while the other half received CIMT.
Study participants were asked to wear the restraint every day, and come in for training every weekday for several hours, for a period of two weeks. They were evaluated immediately after treatment, and again four, eight, and 12 months later, through a series of tasks designed to measure arm dexterity, and a set of questions about how well and how often they used the impaired arm in daily activities.
Compared to the group that received only customary care, the group that received CIMT showed improved function of the stroke-affected arm in timed tasks and in self-reported daily use at all time points. At the earliest time points, some participants were unable to perform certain tasks at all, but those who received CIMT were more likely to regain the ability to perform those tasks by the end of the year-long study period.
Previous neuroimaging studies have revealed that CIMT stimulates increased activity in the part of the brain that controls the rehabilitated arm. "The work of Dr. Wolf and his colleagues shows that it's possible to harness this remarkable plasticity in the brain to significantly improve the lives of patients," said John Marler, M.D., Associate Director of Clinical Trials at NINDS.
Beth Ansel, Ph.D., a project director of the National Center for Medical Rehabilitation Research, the NICHD division that funded the study, said its results represent an important milestone after many years of research. "These studies began as basic research with laboratory animals, progressed to studies with patients, and now are poised to change patient care," she said.
The NINDS and NICHD are components of the National Institutes of Health (NIH) within the Department of Health and Human Services. The NINDS (http://www.
The National Institutes of Health (NIH) -- The Nation's Medical Research Agency -- includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
*Wolf SL, et al. Effect of Constraint-Induced Movement Therapy on Upper Extremity Function 3 to 9 Months After Stroke. The EXCITE Randomized Clinical Trial. JAMA, November 1, 2006, Vol. 296, No. 17, pp. 2095-2104.