It seems like a good idea — make a robot that can put stroke patients through their physical therapy paces. After all, a robot is good at repetitive movements, it doesn't get tired, and you don't have to give it health insurance.
Dept. of Veterans Affairs
Robots help stroke patients, but not any better than human therapists.
Robots help stroke patients, but not any better than human therapists. Dept. of Veterans Affairs
But a new Veterans Affairs study shows that stroke patients didn't do any better with the robot therapist than when they had comparably intense workouts with a human physical therapist.
Still, that's not the most important message from this study, published online today by the New England Journal of Medicine.
The most significant finding is that patients had significant improvement from either kind of intense therapy long after they suffered their strokes. On average, their strokes occurred five years before they enrolled in the study.
That gives a boost to the Holy Grail quest of current stroke rehab research — finding ways to do "brain repair," through drugs, growth factors, electromagnetic stimulation and stem cells, as well as intense physiotherapy.
The study's implication is that stroke patients should get therapy that's more intense and lasts longer than they now do.
Typically stroke patients get PT for only six months, and it's usually not as intense as the regimen that produced improvement in the VA study. In the new study "usual care" didn't do as well as either kind of intense therapy, whether delivered by a robot or a human.
Patients who got three months of intense PT for their arms had an eight-point improvement on a standard scale that measures stroke impact. That's enough to make a big everyday difference in such activities as cutting food with a knife and fork, opening jars and tying shoes.
Even though the therapy focused only on their arms, patients also did better on such things as walking or climbing stairs — probably because their improved arm function they got out and about more often.
Patients had their strokes from six months to 24 years before they enrolled in the study, with an average of four to six years.
"One of the purposes of the study was to up-end the conventional dogma that stroke victims can't recover physiological function," says Dr. Albert Lo, a Brown University neurologist who led the project.
Dr. Steven Cramer of the University of California at Irvine says the study succeeded on this score. It shows that "the adult brain has the capacity for clinically relevant plasticity even in the chronic phase after a stroke," Cramer writes in an accompanying editorial.
Cramer doesn't think the study puts the kibosh on robot therapy, though. They still have a lot of advantages, he thinks.
But don't expect robot PTs to make the therapy cheaper. The study says the average total cost was about the same for patients who got robotic therapy and those treated exclusively by humans.