March 2, 2006

BIRMINGHAM, AL — A rehabilitation therapy designed to improve the function of the weakened or affected arm of a stroke patient has been shown to provide continued benefit for two years, according to a placebo-controlled follow-up study reported in this week’s rapid access issue of Stroke: Journal of the American Heart Association.

Constraint-Induced Movement therapy (CI therapy) involves intense rehabilitation of the affected arm for two weeks while restraining the patient’s unaffected arm over the same period, requiring the patient to use the affected limb. It was developed by UAB (University of Alabama at Birmingham) professor of psychology Edward Taub, Ph.D.

Stroke patients typically lose function in the limbs on one side of the body following a stroke and the traditional belief among rehabilitation professionals has been that the level of motor function at one year post-stroke is the level at which patients will remain. While Taub has previously demonstrated the efficacy of CI therapy, this is the first placebo-controlled trial of the therapy.

“We believe that CI therapy works on two levels,” Taub said. “First, it overcomes what we call ‘learned non-use’, a phenomenon in which patients learn to not use the affected limb because it simply doesn’t work. Secondly, CI therapy appears to produce a ‘re-wiring’ in the brain that leads to improved motor function of the affected limb.”

The research team studied stroke survivors with mild to moderate motor impairment of an upper limb, an average of 4.5 years after stroke. Twenty-one survivors underwent CI therapy for six hours a day for 10 consecutive weekdays. Twenty others had placebo therapy involving a general fitness program of strength, balance and stamina training, games to provide cognitive challenges and relaxation exercises for the same time period.

Taub reports that following the two-week period, CI therapy patients showed “large to very large” improvements in the functional use of their more affected arm in the activities of daily living.

“We use a motor activity log (MAL) in which patients and caregivers note how well and how frequently survivors used their more impaired arm in activities of daily living,” Taub said. “CI therapy patients improved, on average, from little use of the arm (1.3 on MAL) to half as much use as pre-stroke (3 on MAL), while those in the control group reported no change.”

At the two year follow-up, the CI therapy group continued to show a large improvement in MAL scores compared to pre-treatment scores.

“These findings reiterate our contention that chronic stroke patients will benefit from CI therapy, regardless of the length of time that has passed since the onset of the stroke,” Taub said.

The study was funded in part by the National Institutes of Health. Co-authors are Gitendra Uswatte, Ph.D.; Danna Kay King, M.S.P.T.; David Morris, Ph.D., P.T.; Jean E. Crago, M.S.P.T.; and Anjan Chatterjee, M.D.