80% of stroke patients lose use of arm, hi-tech brace could give new hope
(COLUMBUS, Ohio) – Sabrina Pridham knows all too well how quickly life can change. At 33, she was a successful CPA and a young, healthy mother with a sense for adventure.
In the spring of 2000, Sabrina had just buckled herself into the passenger seat of a race car to take lessons in defensive driving from a professional driver. Then, right there on the track, it happened.
“I just turned my head to say something to the driver and my carotid artery dissected immediately,” she said. “It’s extremely rare to have this type of stroke and only about 5 percent of people who have them actually survive.”
Sabrina did survive, thanks to a quick response by medical teams and emergency surgery. But the stroke took a devastating toll. “I had to learn to walk all over again,” she said. “In fact, I had to learn to do a lot of things again. I spent more than two years in rehabilitation.”
But the one thing therapists couldn’t do was help Sabrina regain the use of her left arm. To this day, more than a decade after the stroke, it is completely paralyzed, which, among stroke survivors, is fairly common.
“About 80 percent of stroke survivors have difficulty with arm movement,” said Stephen Page, PhD, FAHA, an occupational therapist at The Ohio State University Medical Center. “Things the rest of us take for granted, like reaching for a book on a shelf or even feeding ourselves, a lot of stroke survivors simply can’t do.”
Most therapists have assumed for decades there was only a small window of opportunity to rehabilitate arms that were damaged by a stroke. They would often focus on the arms early in rehabilitation, but the further away from the stroke a patient got, the less likely it was that rehabilitation would continue.
“It used to be just be an accepted fact that stroke survivors, after a certain period, couldn’t get better,” said Page. “But I don’t buy that.”
So, Page is launching a new study using a hi-tech elbow brace that some simply refer to as a “bionic arm.” Using tiny electrodes attached to the biceps and triceps of a patient’s arm, this device is designed to detect even the slightest intention of movement.
“All of our muscles have what’s called EMG or electromyography,” said Page. “It is essentially a signal that our muscle sends out when it’s moving, or attempting to move,” he said. “When the patients attempt to move, even if it’s slow, or not even visible, this device will magnify those attempts to move and the robot inside will kick in and help them to move the rest of the way.”
But temporarily assisting patients in moving their arms is only part of the strategy. Page, and a growing number of therapists, now believe that the brain can actually be retrained to once again move the arm on its own, regardless of how long ago a patient suffered a stroke.
“We think that with repetitive use of the device that the brain is actually being re-wired,” said Page. “It’s a process called neuroplasticity. With enough work, this can actually restore movement and, so far, our preliminary studies have suggested that it may be happening.”
It’s promising enough that Page’s work is being funded by the National Institutes of Health, who want to learn more about the potential of his “bionic arm.” There are millions of stroke survivors who could use further rehabilitation therapy, not to mention new options for possibly regaining control of their arms.
It was the promise of this technology that motivated Sabrina Pridham to volunteer for Page’s study. “I was very surprised at how easy it was to use,” she said. “All it needed was a small message from my brain and the device immediately responded.”
For more than a decade, Sabrina has been told that she has gotten all the movement she ever will out of her left arm. But just like her therapist, she isn’t buying that either. “They call that plateauing,” she said, “and I believe that, if there’s something there to work with, you can always move past the plateauing.”
Strokes are the third leading cause of death in this country, the leading cause of disability among adults, and cost a staggering $73.7 billion dollars each year¹. Each minute a stroke goes untreated, an estimated 2 million brain cells die¹, often leaving patients permanently impaired.
Page’s study will follow several patients over the next several months to see what kind of impact the “bionic arm” can have in short-term therapy and long-term mobility.
¹Hemiparesis, National Stroke Association, December 2011. Online: http://www.stroke.org/site/PageServer?pagename=hemiparesis