Taking Good Care
Hi-tech Approach Helps Stroke Patients Regain Their Lives
David Rader knew something was very wrong. He suddenly felt dizzy and weak. He’d been working for more than an hour in his sweltering attic in late August 2007, putting in an air-conditioning system, and thought he was suffering from heat exhaustion. His wife, Jean, drove him to the VA hospital, 10 miles away in Lexington, where he was examined and released. But the next day he felt worse. He went back to the VA, where he had a massive stroke.
“His doctor told us he wasn’t going to make it,” Jean recalls. “They said to call our daughter in Florida and call the chaplain. But I know my husband—he’s tough—so I told the doctor, ‘Not so fast,’” she says, spacing out the three words for emphasis.
Jean knew David, 75, was a fighter and that with proper rehab care he could make a comeback. She did call her daughter, Kate, in Florida, because she remembered that Kate knew someone at Cardinal Rehabilitation Hill Hospital in Lexington and that the hospital had a good reputation. So she took David there. This turned out, Jean says, to be an excellent choice. The rehabilitation programs at Cardinal Hill have played a pivotal role in ongoing clinical studies originating from the University of Kentucky.
At Cardinal Hill, David (who we’ll return to shortly) was put into the care of Lumy Sawaki, an associate professor in the Department of Physical Medicine and Rehabilitation at the University of Kentucky, who immediately strikes you as a confident, affable and approachable woman. She included David in one of her four ongoing research projects that she brought with her from Wake Forest University when she came to UK last year as the Cardinal Hill Endowed Research Scholar in Stroke and Spinal Cord Injury Rehabilitation.
“The common ground of all these studies is measuring the effects of intensive, task-oriented therapy that uses the latest technology to help stroke patients, some of whom have suffered major, life-changing damage,” says Sawaki, her English tinged with the flavor of her native language—Portuguese. (She was born and grew up in Brazil.) The titles of three of her projects include the word “neuroplasticity,” which refers to the brain’s ability to reorganize itself by forming new neural connections to compensate for injury and disease.
The Brain Can Find a Way
In conventional stroke treatment, therapists frequently focus on teaching patients how to compensate for loss of function on one side of the body by making greater use of the unaffected side. However, this compensatory approach does not address the potential for the affected side to recover some function.
During the last two decades, scientists have learned that the brain is able to relearn and redirect more activity after a stroke injury than previously thought possible. Neuroimaging techniques, like fMRI, which shows the functional activity of the brain, have revealed that remarkable changes can occur after constraint-induced movement therapy (CIMT). This approach involves constraining the use of a stroke patient’s non-affected arm with a mitten for 90 percent of his waking hours for two weeks so that the weaker arm will have to do more of the work in daily activities. In this way, use of the weaker arm triggers new neuronal brain activity. The really good news is, brain rewiring can occur even for patients who had a stroke 10 or 20 years ago.
Sawaki was the lead author on a CIMT study published last year in the journal Neurorehabilitation and Neural Repair. In this multicenter study, 30 subjects between three and nine months after their stroke were randomly assigned to the experimental group (who received CIMT immediately after initial evaluation) or the control group (receiving CIMT after four months). Each subject was evaluated using transcranial magnetic stimulation (TMS), a noninvasive method to excite neurons in the primary motor cortex, located toward the back of the frontal lobe. The job of the motor cortex is to plan and execute movements.
Here’s how TMS works. By positioning a handheld, wand-like device on a patient’s head, a therapist induces weak electric currents in the patient’s brain tissue to trigger brain activity. When TMS is used to stimulate an area of the brain that controls movement of a particular muscle, that muscle will move. By stimulating multiple brain areas and monitoring muscle response, the therapist can map the brain area that controls a particular muscle and compare this map to previous patterns of activity. As the patient’s ability to perform a certain movement improves, these brain maps confirm the reorganization of the associated area of the brain.
“Both groups in this study demonstrated improved hand-motor function two weeks after baseline,” says Sawaki, “but the experimental group showed significantly greater improvement in grip force after the intervention and at follow-up.” In the experimental group, CIMT produced significant improvements in damaged arm motor function, she explains as she demonstrates, moving her right arm side-to-side. This group also had an increase in the TMS motor map area compared with the control group over a four-month period, which provided evidence that the constraint-induced approach led to new and functionally significant neuronal reorganization.
In discussing the importance of TMS in mapping areas of new neuron activity, Sawaki cites a breakthrough study by Harvard neuroscientist Alvaro Pascual-Leone. Volunteers with no neurological disorders were brought into a Harvard lab to learn a five-finger exercise on a piano keyboard connected to a computer. The subjects did a two-hour practice session for five consecutive days, and each day’s practice was followed by a test that measured their progress. Before the first practice session and every day afterwards, Pascual-Leone and his team used TMS to map the motor cortical areas that target finger flexor and extensor muscles. As the subjects’ performance improved, the size of the cortical representation in the brain for both muscle groups increased significantly.
“But he didn’t stop there,” Sawaki continues. “He had a second group of subjects merely think about practicing the piano exercise.” They played the simple piece of music in their head, holding their hands still while imagining how they would move their fingers. Then the volunteers sat beneath the TMS coil. Pascual-Leone saw that the cortex region that controls the piano-playing fingers also expanded in the brains of volunteers who simply imagined playing the music—just as it had in those who actually played it. This discovery did nothing less than show that mental training had the power to change the physical structure of the brain. That finding is the basis for Sawaki’s work with severely affected patients like David Rader to guide them to move stroke-affected areas that previous therapists had given up for dead.
Reading a Patient’s Brain Map
Scientists have long known which parts of the brain control which parts of the body. Humans spend a lot of time talking and manipulating objects with their hands, so we have large amounts of cortex devoted to mouth, tongue and hands. (Different species have different patterns. Rats get a lot of information from their whiskers, so a large amount of sensory cortex is devoted to the whiskers.)
“It’s this ‘cortical priority’ that, early on, inspired some therapies for brain-damaged patients,” Sawaki notes, “and it’s the basis for our CIMT work.”
In one of Sawaki’s current studies, she is pinpointing clusters of new neurons and, through some trial and error, figuring out which parts of a patient’s damaged tissue are triggered by activating these neurons. This work is made possible through the development of a futuristic offshoot of TMS called transcranial direct current stimulation (tDCS), which involves applying weak electrical currents to the head to generate an electromagnetic field to excite and fire neurons. Sawaki uses this technology in conjunction with TMS.
In several of her studies, she is also using peripheral nerve stimulation (PNS) to increase the brain’s ability to reorganize. “In each PNS session, three nerves in the subject’s affected arm are stimulated by mild electrical pulses,” Sawaki explains. “These pulses travel to the brain and excite areas in the motor cortex.” Each session lasts two hours and is followed by intense, task-oriented occupational therapy.
The new technology is wonderful, Sawaki says, exuberantly, but any success—movement in the damaged area of the body—is highly dependent on the patience and perseverance of the stroke victim. “I think of myself as a guide in this process. Once I find the area of the brain where I believe new neurons are taking over a movement function, I tell the patient to envision moving that area.” This is analogous to the work of Pasqual-Leone, who asked volunteers to envision practicing a piano exercise.
But how can someone imagine moving, say, a stroke-damaged finger? How can we think about something the body has always done automatically?
“This is actually very common,” Sawaki says. “In people who have lost a limb, for example, there is still the perception of sensations, usually including pain, in the missing arm or leg. The brain still gets messages from the nerves that originally carried impulses from that limb. Amputees often talk about being able to ‘move’ their missing limb.” And more to the point, Sawaki knows that when patients envision the process of movement, this mental picture facilitates the brain’s rewiring.
Two Recent Successes
When David Rader became Sawaki’s patient, he wasn’t optimistic about his chances of recovering any movement in his damaged arm or leg. His wife, Jean, placing a hand on her husband’s shoulder (David is still unable to speak), sadly states that his whole left side was still without feeling a year and a half after the stroke. After he completed traditional therapy through home health and outpatient services, his daughter, Kate, convinced him to try working with the UK neurorehabilitation research team at Cardinal Hill. There, Sawaki placed David in one of her studies, which lasted two weeks.
“Two weeks might seem like a short time,” Sawaki says, anticipating the question of the study’s brevity, “but this is very intense work.”
She used TMS to determine which parts of David’s brain controlled his arm and hand. Based on that evaluation, Sawaki gave him experimental treatment for two hours a day, followed by four hours of intensive, task-oriented occupational therapy. This training often involved work with a robotic arm (see “Rehab Robots”). His progress was slow, but then came the breakthrough.
“Toward the end of the second week,” Sawaki says, “we were continuing to focus on Mr. Rader’s damaged arm in daily PNS sessions. After stimulation during one of these sessions, I told him to envision moving the muscle in his arm that we had targeted; and suddenly his arm moved.”
“David was both surprised and thrilled,” his wife exclaims, recalling the moment. “Now he can move his arm, which he thought he would never do. And because he knows now he can move it, he’s more motivated to work at home to move it even more. It’s wonderful.”
In October 2004, stroke attacked Wendall Trent, 33, in his sleep. When he went to bed, he felt fine, he said, maybe just a bit sore from a tough workout instructing his martial arts class. He’d been thrown by another instructor and “landed wrong.” But he didn’t think much about it until he woke up at 2:30 a.m. next to his bed on the floor, the whole left side of his body without feeling. His wife drove him to St. Claire Regional Medical Center in Morehead, Kentucky, close to where they live, and the prognosis was bleak: “The doctors said my carotid artery had been torn, that I’d never be able to use my arm or hand again, or walk again,” Wendall states, solemnly.
He was taken by helicopter to the UK Hospital, where a stent was put in his neck. After four days in critical care, Wendall was taken to Cardinal Hill, where he had inpatient therapy for two months. By February 2005, he was able to stand up and take a few steps, but his left arm and hand failed to respond to traditional rehab exercises.
Four years passed, and still he had no feeling in his disabled arm and hand. Then he decided to return to Cardinal Hill and see if he could be helped through the new rehabilitation research program he’d heard about there. “I was paired up with Lumy and was impressed with her from the beginning. She has a great can-do attitude—no negativity is allowed in. The therapy was strenuous, but I stuck with it.”
In March of this year, working with Sawaki’s team and their neurorehabilitation techniques, Wendall envisioned his left pinkie finger moving—and it moved. “I thought, ‘Wow! There’s some progress!’ Her expertise on this high-tech equipment has given me new hope. The whole process reminds me of hotwiring a car,” he laughs. “It’s another step on the road to recovery.”
Sawaki is pleased by the progress these two patients—and others—have made, but she re-directs any praise aimed at her to the patients themselves. “Yes, I have the tools here to ‘facilitate’ the rewiring process, but it’s the effort and desire of the patient that ultimately determines the outcome. I’m simply helping these people help themselves.
“Everybody who comes here improves. My mission here is beyond that,” Sawaki says. “I want every patient to be able to go back to their jobs or their lives and be physically able to do things again. That’s the big goal.”
“Lumy’s work is the perfect match for the type of research program we are building here,” states her colleague Joe Springer, professor of physical medicine and rehabilitation at UK and research associate in UK’s Spinal Cord and Brain Injury Research Center. Springer is one of several UK faculty members located at Cardinal Hill. “Following our growing understanding of the brain’s potential for neuroplasticity, her focus on identifying novel neurorehabilitation strategies is moving us into important, uncharted territory.”
Rehab Robots—Partners in Recovery
The latest robotic technology is helping patients like David Rader and Wendall Trent regain movement and balance. In January 2008 the Lokomat robotic system debuted at Cardinal Hill Rehabilitation Hospital in Lexington, which has a close affiliation with the UK College of Medicine. The Lokomat’s harness and lift system raises patients from a wheelchair and places them in a standing position on the treadmill. Robotic devices attached at the patient’s thighs and knees provide support to properly “unweight” the patient. The Lokomat then operates at an appropriate speed, creating a walking rhythm.
Cardinal Hill is the only facility in the state to offer Lokomat treatment to the public and one of only 25 in the country used for therapy, says Kara Lee, a doctor of physical therapy and coordinator of the Lokomat program in the Center for Outpatient Services at Cardinal Hill. An anonymous donation made in honor of Dusty Hicks, a Central Kentucky teenager injured in a diving accident in 2006, made the Lokomat purchase of possible.
This equipment simulates natural walking patterns, actual pace and gait, Lee explains. When she talks about working with patients who use the Lokomat, she charges the air with enthusiasm and makes you think she is a perfect fit for the job she’s chosen. The latest virtual reality software is an important part of this, she continues, gesturing to a large screen that faces the patient. As he walks in the harness, his avatar chases various animals and tries at the same time to avoid enemy dogs. “Software registers different amounts of force on each leg. Lokomat teaches people to walk at a faster pace, go around objects, and regain balance.”
A physical therapist and a student intern can change three parameters as needed: body weight support, speed, and the percentage of work the robot does. A typical intervention program involves working with the Lokomat for six to eight weeks, twice a week, doing 45-minute sessions. “We’ve had more than 200 people use this so far,” notes Lee, “and it’s booked solid from 9 to 5, five days a week. We would love to have a second one, honestly—it would likely be booked solid, too. It’s amazing how much progress someone can make using this equipment.”
See the Lokomat in action: http://www.youtube.com/watch?v=CWGJUOJqb-Q.
Sawaki enlists the aid of another robot in her comprehensive approach to helping stroke victims. This device, an upper extremity robotic therapy system, is able to mimic a fluid, natural extension of the patient’s arm using pneumatic “muscles” and can be programmed for repetitive exercises specific to the user that improve arm and hand flexibility and strength. “Our goal with this device is to help stroke survivors regain the ability to perform basic tasks, such as reaching for objects or feeding themselves,” Sawaki says, pushing a button that stirs the robotic arm to life.
Here’s how one of the exercises works. The patient is buckled into a swivel chair—imagine being strapped into a barber chair—and the stroke-affected arm is placed in a large cuff. The patient’s hand wraps around a joy stick to control movement of a large dot on a video screen. The patient is asked to move the dot from the center of the screen and place it in various outer circles, moving it up and back as directly as possible.
“It’s like a video game,” Sawaki says, “with one major difference. If you go too far astray on any given task, the robot takes over and moves your arm in the right direction. Repetition and intensity are the two main elements of this exercise. The robot does 960 repetitions per session, which would totally wear out any therapist!”
The robot in this way helps the patient reestablish the brain-arm connection, as does all training, she adds, emphasizing that this is intense therapy: it demands up to four hours of active participation daily and up to two hours of experimental treatment beforehand for two consecutive weeks. The UK Healthcare Stroke and Spinal Cord Neurorehabilitation Research Program at Cardinal Hill has the only robotic arm in Kentucky.
Working with biomedical engineer Kenneth Chelette, Lumy Sawaki uses transcranial magnetic stimulation (TMS) to induce electric currents in the brain tissue of stroke patient David Rader. When TMS stimulates an area of the brain that controls movement of a particular muscle, that muscle will move. After stimulating multiple brain areas and monitoring muscle response, Sawaki maps the brain area that controls a particular muscle. These maps confirm the reorganization of neurons in the brain. Sawaki is an associate professor in UK’s Department of Physical Medicine and Rehabilitation.
These images show a stroke patient’s brain before (A) and after (B) therapy. The dots represent muscle activation; the lighter the dot, the more activation in that area of the brain. If the motor cortex (highlighted yellow area) is damaged by a stroke, neuron regeneration often happens next door in the sensory cortex (highlighted white area). Brain map B shows significant improvement in muscle activation in the motor and sensory cortex on both the stroke-damaged and non-stroke sides of the brain. These 3D renderings were created using software called Brainsight.
Joe Springer, a professor of anatomy and neurobiology, is heading up the research program in physical medicine and rehabilitation at UK and Cardinal Hill Rehabilitation Hospital in Lexington. Springer, who also serves as a research associate in UK’s Spinal Cord and Brain Injury Research Center, is one of several UK faculty members located at Cardinal Hill.
Physical therapists Dana Lykins and Matt Kudron help stroke patient David Rader on the treadmill of the Lokomat, which simulates natural walking patterns. This system uses a harness and lift system to place patients in a standing position, and robotic devices attached at the thighs and knees provide support to properly “unweight” the patient. The Lokomat is located at Cardinal Hill Rehabilitation Hospital in Lexington, which has a close affiliation with the UK College of Medicine.