Stroke patients who receive constraint-induced movement therapy (CIMT)--a rehabilitative technique that restrains the less-impaired arm, show significant improvement in arm and hand function, according to a seven-center national study led by Emory University researchers. The findings will appear in the Nov. 1 issue of the Journal of the American Medical Association (JAMA).
Known as the EXCITE trial, for Extremity Constraint-Induced Therapy Evaluation, the study enrolled 222 patients who had suffered from predominantly ischemic stroke (the most common form, in which a blood vessel becomes clogged) within the previous three to nine months.
The study involved restraining the less-impaired hand and/or arm with an immobilizing mitt during working hours in an effort to encourage use of the affected extremity. Patients then engaged in daily repetitive task and behavioral shaping sessions, which included training in tasks such as opening a lock, turning a doorknob, or pouring a drink. Participants were assigned to receive either the CIMT technique or usual and customary care.
Patients were evaluated using the Wolf Motor Function Test, a measure of laboratory time and strength-based ability and quality of movement (functional ability). Additionally, the Motor Activity Log measured how well and how often 30 common daily activities were performed.
Investigators found that over the course of a year from the beginning of therapy, the CIMT group showed greater improvements than the control group in regaining function, including a 52 versus 26 percent reduction in time to complete a task and a 24 versus 13 percent increase in the proportion of tasks performed more than 50 percent of the time with the partially paralyzed arm, compared to pre-stroke levels.
"The basic principal behind constraint-induced therapy is re-teaching a patient to regain use of his or her impaired limb by limiting their use of the good one," said Steven L. Wolf, PhD, professor of rehabilitation medicine at Emory University School of Medicine and the study's principal investigator. "Often, stroke rehabilitation has primarily focused on teaching patients how to better rely on their stronger limbs, even if they retain some use in the impaired limbs--creating a learned disuse."
According to Dr. Wolf, until now, research into constraint-induced therapy for stroke rehabilitation has centered primarily on chronic stroke patients, defined as those who experienced stroke more than a year previously. The EXCITE trial represents the first national, randomized, single-blinded study to test the effects of therapy on patients with the ability to initiate movement at the wrist and fingers, and who had experienced a first stroke within three to nine months prior to enrollment.
"Administration of CIMT showed statistically significant improvements in motor ability and use compared with participants receiving customary care only," said Dr. Wolf. "These findings suggest that further research exploring central nervous system changes that accompany observed motor gains and research on alternate models of CIMT delivery are warranted. CIMT should be considered as a valuable form of rehabilitation."
Each year more than 700,000 Americans suffer from stroke, and approximately 85 percent of stroke survivors experience partial paralysis on one side of the body. The annual health care costs for stroke care is approximately $35 billion.
The study was supported by a National Institutes of Health grant from the National Center for Medical Rehabilitation Research (National Institute of Child Health and Human Development) and the National Institute of Neurological Diseases and Stroke.
"This is an example of two NIH institutes working together to address an important clinical problem," said NIH Director Elias Zerhouni, MD. "This study is likely to have a significant impact on clinical care for stroke survivors."
In addition to Emory, other centers involved in the study include the University of Alabama at Birmingham (which served as the training center for evaluators and interventionists); Washington University in St. Louis (which served as the data management center); the University of Florida; Ohio State University; University of Southern California; University of North Carolina at Chapel Hill; and Wake Forest University.