A placebo-controlled study shows that constraint-induced (CI) movement therapy produces large, long-lasting improvements in patients with chronic stroke, researchers report.
Patients showed an improvement from 9% of their pre-stroke function in their most-affected arm to 52% after six hours of daily CI therapy for 10 consecutive days, Dr. Edward Taub of the University of Alabama at Birmingham and colleagues report. The improvement persisted for two years after the therapy, which patients completed a mean of 4.5 years after stroke.
In CI therapy, patients undergo a type of intensive training, called "shaping," of the more-affected upper extremity, while the less-affected extremity is restrained.
In the current study, 20 patients were assigned to a placebo program including a fitness regimen with strength, balance and stamina training exercises; games designed to provide cognitive challenges; and relaxation exercises. Questionnaires showed that patients in this group had similar expectations of how helpful the intervention would be compared to those in the CI group.
No significant improvements were seen in the placebo group, but the 21 patients who underwent CI showed "large to very large" improvements in the function of their most-affected arm as measured by the Wolf Motor Function Test, the Motor Activity Log, and the upper extremity actual amount of use test. Improvements persisted at two years post-therapy.
CI works by two independent but linked mechanisms, Dr. Taub explained: overcoming learned non-use and use-dependent neural plasticity. He and his colleagues have now treated over 500 patients, who retain an average of 80% of their improvement over two years, he said.
The approach "works in virtually every patient," he added. "Our oldest patient today is 92 and she had a lab-average treatment effect," he said, adding that another patient was treated successfully 50 years after a stroke.
Patients are still told that it is impossible for them to have functional improvement one or two years after stroke has occurred, Dr. Taub said. CI therapy, he concluded, "offers them hope for the first time."