Researchers studied 13 young adults (aged 17-21) who had muscle weakness or partial paralysis in an arm following severe traumatic brain injury or stroke during two three-week phases at a rehabilitation clinic in Germany. Arm movement didn't improve significantly during the first phase, which was a placebo where patients had occupational therapy for 90 minutes each day.
During the second phase, patients received shaping training for 90 minutes each day, and arm movement improved for all patients. In a questionnaire designed to indicate motor activity, patients responded that the amount of use with their affected arm rose from an average of rare use to three-quarters of how much it was used before the stroke. Quality of movement rose from "very poor" to a level between "poor" and "fair." Improvements remained stable during the four-week follow-up of the third phase.
Shaping therapy is based on conditioning behavior: Patients are trained individually to perform increasingly difficult tasks with their affected arm, and then are rewarded for improvement. Tasks involved everyday activities, such as pressing a light switch, moving a chair and pulling up socks. Patients received encouragement from clinical staff as a reward after completing a task.
"Prior to shaping, the patients' affected arms had reached a low-functioning plateau for several months or years, in some cases," said study author Annette Sterr, PhD, of the University of Liverpool in England. "The study shows that shaping – training, repetition and working with the affected limb – makes progress and helps the brain to adapt."
Shaping therapy borrows from another behavior-based treatment called Constraint-Induced Movement Therapy, yet there are differences in time commitment and constraint use. Daily shaping sessions were much shorter (90 minutes in the study) than the typical six-hour sessions with constraints. With a constraint, the unaffected arm must be in a sling during awake hours to force movement in the affected arm. Some doctors are concerned that patients won't wear the constraint correctly at home. In a clinical environment the full Constraint-Induced Movement Therapy program is often viewed as impractical due to the time and resources involved, Sterr said.
While shaping is applicable to patients at various levels of limb recovery, its success without constraints doesn't mean that constraints are irrelevant. The combination of constraining the unaffected arm and training the affected one would likely increase the neural activity in the motor system even more, leading to better outcomes, according to the study.
"We hope that our results help to promote training programs, and the CI Therapy concept in particular, in standard clinical practice," said Sterr. "They are promising results but need to be tested in a larger group of patients with a longer follow-up period." A five-year research program was recently awarded to Sterr to continue this research at the University of Surrey, England, where she has accepted a position.
This study was supported by grants from the Germany Research Foundation and The Royal Society (UK).
The American Academy of Neurology, an association of more than 18,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as stroke, Alzheimer's disease, epilepsy, Parkinson's disease, autism and multiple sclerosis.
For more information about the American Academy of Neurology, visit its web site at www.aan.com.
Journal
Neurology