LOS ANGELES – A robotic device combined with standard occupational* therapy helped stroke patients with hemiplegia gain significantly more function in their affected arm, compared with similar patients who received physical therapy and an at-home exercise program.
The Japanese ReoGo robot was especially effective in patients with moderate to severe hemiplegia, Kayoko Takahashi, Sc.D., reported at the International Stroke Conference.
The difference in response between more and less severely affected patients might have been related to their baseline physical abilities, Dr. Takahashi said during a Feb. 10 press briefing at the meeting. "It could be that the patients with lower function had difficulty performing their self-training exercises correctly. Those with severe hemiplegia could use their nonaffected arm to help with exercise, so perhaps the unaffected arm helped too much and the affected arm did not get enough exercise."
With the robot, she added, the affected arm must do all its own work.
Dr. Takahashi reported the results of a randomized, open-label trial of the robotic training device, which is manufactured by Teijin Pharma Ltd. The robot consists of two interconnected platforms: a seat with an armrest that accommodates the affected arm, and a computer screen with targets toward which the armrest reaches. The targets lead the arm though a series of movements that replicate the normal ranges of motion in the elbow and shoulder joints.
The device can be programmed in five levels, depending on the patient’s baseline physical ability. The highest assist level is completely automatic; the lowest is completely patient guided. As the patient progresses through recovery, the machine allows for more and more self-directed movement, said Dr. Takahashi, an occupational therapist at the Kitasato University East Hospital in Kanagawa, Japan.
Her study group comprised 56 patients (mean age, 65 years) who were treated at any of six Japanese hospitals. All of the patients had suffered a stroke within the previous 4-6 weeks, with a mean time after onset of 47 days. All of them had experienced upper extremity hemiplegia of varying degrees. The baseline Fugl-Meyer Assessment (FMA) score of motor function after stroke was an average of 30 for the upper extremity total, 19 for the shoulder/forearm synergy, and 7 for the flexor synergy. (The scoring system ranges from 0-100, with 0 indicating hemiplegia and 100 indicating normal motor performance. The range for the lower extremity is 0-34, and for the upper extremity – which is used in this study – is 0-66.) Patients in this study with a score lower than 30 were considered to have moderate disability. "For example, they may be able to hold a cup still [on the table], but not raise it to their mouth."
The patients were randomized to one of two rehabilitation routines. Each day for 6 weeks, the experimental group underwent 40 minutes of standard occupation/physical therapy plus 40 minutes of self-directed exercises conducted at home. The control group received the standard 40-minute occupational/physical therapy plus 40 minutes of therapy on the robot. The primary outcome measure was change in the FMA score.
Overall, there was no significant between-group difference in total FMA score, although the robotic therapy group significantly improved its upper extremity synergy movement score, compared with the control group.
The groups were then further divided into functional categories, using a score of 30 as the cut-off point. Those with a score higher than 30 were considered to have mild impairment, and those with a score of 30 or lower were deemed to have moderate to severe impairment.
In this subcomparison, the lower-functioning group that used the robot achieved a significantly better overall score than did the lower-functioning control group. There was also a significant difference between the treatment groups, with the lower-functioning patients improving significantly more than the higher-functioning group. "This shows that patients with moderate to severe hemiplegia may benefit the most from robotic therapy," Dr. Takahashi said at the meeting, which was sponsored by the American Heart Association.
Those patients with low and high proprioception both benefited from the device. "They are reaching for the monitor image, so this can give them feedback about where the arm is and how it’s moving." Dr Takahashi said. Sensory perception is not required to benefit from the training, she added.
Although the device is still in its research phase, Dr. Takahashi said it has a financial as well as clinical benefit. "This is considered a cost-saving device because now what we, as therapists, do is spend most of the session focusing on improving impairment, and not as much time focusing on function. With the robot now working on impairment, therapists can focus completely on activities of daily living and the functional area, which is a great benefit to the client."