Whether performing virtual task-specific repetitive practice using a robotic orthosis or actual task specific practice supervised by a physical therapist, independent post-stroke survivors significantly reduced impairments with no significant differences in gains between the two groups, according to recent study results. However, researchers could not translate improving comfort and increasing voluntary control of movement, flexibility and strength at the shoulder and elbow into measurable gains in fine motor hand control, activities of daily living or independence.

“It has been proposed that rehabilitation robotics have the potential to not only provide the necessary repetitions to maximize recovery, but in fact they can facilitate the progression of difficulty, provide feedback about accuracy and potentially even make the training fun,” Nancy Byl, MPH, PhD, PT, FAPTA, of the Department of Physical Therapy and Rehabilitation Science at the University of California, San Francisco, told O&P Business News. “Although rehabilitation today focuses on forced use of the most affected upper limb post-stroke, it is not clear whether recovery of the affected upper limb would be greatest with unilateral training of the limb alone or bilateral upper limb training with the least affected side facilitating functions in the most affected limb.”

Physical therapy vs. robotic orthosis

Researchers randomly assigned 15 community independent stroke survivors to an actual task specific repetitive training (TSRT) group working with a physical therapist (PT), a virtual TSRT group guided by a robotic orthosis used bilaterally (BRO) or a virtual TSRT group guided by the robotic orthosis used unilaterally (URO) and compared outcomes.

Overall, study results showed significant improvements in depression, flexibility, strength, tone, pain and voluntary movement after 6 weeks of training in all participants. Upper Extremity Fugl Meyer (FM) scores and range of motion significantly improved in each training group without significant group differences. Although arm impairments around the shoulder and elbow were significantly reduced in both virtual and actual TSRT performed with a robotic orthosis or a physical therapist, there were no significant gains in fine motor hand control, activities of daily living or independence.

According to study results, the TSRT-PT group made slightly greater gains on the FM, motor performance skills and self care-independence compared with the robotic groups. While the TSRT-URO and the TSRT-PT groups had the greatest reduction on the Ashworth Test, the TSRT-URO group had the greatest gains in motor proficiency speed and the TSRT-BRO group had the greatest gains in strength.

“Even in the chronic phase post-stroke (1 to 15 years post-stroke), additional recovery of function is possible following goal oriented, progressive repetitive training,” Byl said. “Supplementing one-on-one physical therapy with training with rehabilitation robotic devices may be the most efficient way to achieve the necessary repetitions to facilitate maximum recovery. Training centers should be created with rehabilitation robotic devices where patients can come and practice under some supervision.”

Robotic orthoses at home

In the current study, researchers identified “important parameters about task specific training of the upper limb that can be integrated to assist clinicians and researchers to develop randomized, longitudinal clinical trials to continue to clarify which variations in task specific repetitive training with and without robotic technology are critical to maximizing recovery, chronic post stroke.”

In a future study, Byl and colleagues will add a hand to the upper limb robotic device and repeat the study with patients who are less than 2 years post-stroke, along with a group of one-on-one therapy combined with unilateral robotic training and one-on-one therapy combined with bilateral robotic training.

“Ultimately, it would be ideal if rehabilitation technology could be used at home to maximize training,” Byl said. “It will be necessary to make the rehabilitation robotics easy to use, cost effective, easy to maintain and available for home use, at least on a rental or loan basis.” — by Casey Murphy