Fred Kemp, 38, a former restaurant manager in Atlanta, Ga., has one simple goal: To open a refrigerator door with his left hand.
Five years ago, Kemp suffered a stroke as he dozed in front of his TV. When he woke up, he recalled, “I couldn’t get up. I tried again and again. I couldn’t move my left side,” forcing the former military hospital corpsman to dial 911 for an ambulance with his good right hand.
Ever since – until very recently – doctors gave him little hope that he would regain use of his left arm.
Every year, 600,000 Americans like Kemp have a stroke, a kind of heart attack in the brain caused by a blood clot or hemorrhage. Many stroke victims die, and many others don’t get effective treatment because they don’t get to the hospital soon enough. Indeed, stroke is still the third leading cause of death in America, after heart disease and cancer.
But, increasingly, people are surviving strokes. While that’s good news, it also means that there are more than 4.4 million stroke survivors living with varying degrees of disability.
Now, preliminary research shows that rehabilitation of long-paralyzed arms and legs may be far more possible than doctors once believed, at least for some types of stroke survivors. At the mecca for stroke rehabilitation, the University of Alabama at Birmingham, victims such as Kemp are achieving recovery levels once thought impossible.
There, psychologist Edward Taub has pioneered a simple but dramatic approach. It’s called CIM – constraint-induced movement therapy, or, as some put it, tough love.
The therapy involves putting the unaffected arm in a splint for most of a patient’s waking hours for two weeks and getting the patient to spend six hours every day using the bad arm in a series of increasingly precise exercises. For the therapy to work, the stroke survivor must have some control over the bad arm, such as the ability to open and close the hand.
To the astonishment of many in the stroke rehabilitation field, this approach seems to work, perhaps by rewiring parts of the brain or spinal cord.
“The idea that people can still experience improvement in the use of the affected side even years after their stroke, this is a revolutionary concept,” said Dr. Leonardo Cohen, chief of the human cortical physiology section at the National Institute of Neurological Disorders and Stroke. “The new approach, now being studied across the country, provides for the first time a treatment alternative for stroke patients, at a time when it was thought there was no treatment.”
One scientist who is not surprised at the way the new therapy is catching on is Taub. Back in the 1970s, Taub began working with monkeys who had had the sensory nerves surgically cut in one arm, but not the motor nerves. The monkeys could feel nothing in the bad arm, but the nerves that control movement were still intact.
Typically, Taub said, the monkeys learned that the bad arm was useless because they couldn’t feel anything. They’d try to move that arm, fail, and soon stop trying, a lesson that Taub calls “learned non-use.”
But, when he put a straightjacket on the monkey’s good arms, the results were remarkable. The animals started using their bad arms within two hours, Taub said, and, after just a week of training, used them fairly normally for the rest of their lives, even when their nerves had been injured as long as four years before treatment.
Recently, Taub and others have achieved similar results in people up to 21 years after they have survived strokes. So far, the method has been tried in about 200 patients.
In research published in June in the journal, Stroke, Taub, working with a German team led by Dr. Joachim Liepert, studied 13 people who had had strokes at least six months earlier and found that they were able to regain75 percent of their arm movement with constraint-induced movement therapy.
Moreover, a brain-mapping technique called Transcranial Magnetic Stimulation, or TMS, showed that, after constraint therapy, the part of the brain that controls the stroke-affected arm doubled in size, getting back nearly to normal.
That suggests that the damaged part of the brain might actually be coaxed to work again. In addition, the constraint therapy seems to boost activity in the side of the brain that does not control the paralyzed limbs. (Normally, the right side of the brain controls the left side of the body, so a stroke in the right brain may paralyze the left arm and leg.) That suggests that, for a person who had a stroke in the right brain, the left brain might be coaxed to take over the right’s work.
TMS does more than just show scientists what’s going on in the brain. It can also be used to change the pattern of electrical activity in parts of the brain, a technique that has already been used to treat severe depression.
In TMS, a coil of wire is placed on the head and an electrical current is passed through the wire in a rapid on-off pattern. That triggers a brief magnetic pulse that excites nerves in a specific region of the brain. Depending on how rapidly the current is turned on and off, the magnetic pulse can either increase or block nerve activity in the targeted brain area, explained Dr. Alvaro Pascual-Leone, director of the laboratory for magnetic brain stimulation at Beth Israel Deaconess Medical Center in Boston.
This suggests that, perhaps even without constraint therapy, TMS could be used to rewire the brain and restore movement to paralyzed limbs, though this has not yet been shown. And there’s one big caveat: Scientists must learn to control TMS sufficiently so that they don’t inadvertently block nerve activity where they’re trying to increase it. “That could actually make the outcome worse,” Pascual-Leone said.
For the immediate future, though, constraint therapy is grabbing the attention of patients and researchers, even though most insurers do not yet cover the technique.
At the National Institute of Neurological Disorders and Stroke, Cohen is analyzing the results of a controlled trial to see whether the constraint therapy is superior to conventional therapy, in which the patient is relatively passive and the therapist moves the patient’s paralyzed arm or leg.
At Emory University in Atlanta, neuroscientist and physical therapist Steven Wolf has begun enrolling 240 patients at seven medical centers around the country in a constraint therapy study called the EXCITE trial.
Like Taub’s monkeys, people learn not to use their weak arm or leg after a stroke, Wolf said, a problem made worse by the trend toward shorter hospital stays. Instead of being hospitalized for months as patients once were, most stroke victims are out in 14 days, which means “about the only thing a rehabilitation specialist can do is train people to get from the bed to the wheelchair,” he said. “That reinforces the notion of how not to use the impaired arm.”
In Boston, Judith Schaechter, who is both a neuroscientist and a physical therapist, has tried constraint therapy on four patients at Northeastern University. All four made clear gains, said Schaechter, who has moved her research to Massachusetts General Hospital.
One of her patients, Richard Mahoney, a 54-year-old Boston man who had a stroke last summer, barely used his right arm before constraint therapy. The treatment “helped me immensely,” he said. Now he uses his right hand all the time.
And Fred Kemp? After only three days of constraint therapy, he was able to open a refrigerator door with his bad left hand without having to think much about it. “I know I can open it. I couldn’t before.” The therapy is rigorous, he added. But it’s “going to be worth the effort to me to get something back.”
For more information on constraint-induced movement therapy, call:
- The University of Alabama at Birmingham, Taub Training Clinic, at205-975-9799.
- The EXCITE trial, headquartered at Emory University, at 404-712-2222 begin_of_the_skype_highlighting 404-712-2222 end_of_the_skype_highlighting.
- Behavioral Neurorehabilitation Unit, Beth Israel Deaconess Medical Center, at 617-667-4074 begin_of_the_skype_highlighting 617-667-4074 end_of_the_skype_highlighting.