An Exploratory Investigation on the Use of Closed-Loop Electrical Stimulation to Assist Individuals with Stroke to Perform Fine Movements with Their Hemiparetic Arm

Abstract

Stroke is the leading cause of upper limb impairments resulting in disability. Modern rehabilitation includes training with robotic exoskeletons and functional electrical stimulation (FES). However, there is a gap in knowledge to define the detailed use of FES in stroke rehabilitation. In this paper, we explore applying closed-loop FES to the upper extremities of healthy volunteers and individuals with a hemiparetic arm resulting from stroke. We used a set of gyroscopes to monitor arm movements and used a non-linear controller, namely, the robust integral of the sign of the error (RISE), to assess the viability of controlling FES in closed loop. Further, we explored the application of closed-loop FES in improving functional tasks performed by individuals with stroke. Four healthy individuals of ages 27–32 years old and five individuals with stroke of ages 61–83 years old participated in this study. We used the Rehastim FES unit (Hasomed Ltd.) with real-time modulation of pulse width and amplitude. Both healthy and stroke individuals were tested in RISE-controlled single and multi-joint upper limb motions following first a sinusoidal trajectory. Individuals with stroke were also asked to perform the following functional tasks: picking up a basket, picking and placing an object on a table, cutting a pizza, pulling back a chair, eating with a spoon, as well as using a stapler and grasping a pen. Healthy individuals were instructed to keep their arm relaxed during the experiment. Most individuals with stroke were able to follow the sinusoid trajectories with their arm joints under the sole excitation of the closed-loop-controlled FES. One individual with stroke, who was unable to perform any of the functional tasks independently, succeeded in completing all the tasks when FES was used. Three other individuals with stroke, who were unable to complete a few tasks independently, completed some of them when FES was used. The remaining stroke participant was able to complete all tasks with and without FES. Our results suggest that individuals with a low Fugl–Meyer score or a higher level of disability may benefit the most with the use of closed-loop-controlled FES.

The Use of Functional Electrical Stimulation on the Upper Limb and Interscapular Muscles of Patients with Stroke for the Improvement of Reaching Movements: A Feasibility Study

“…Makowski et al (42) and Lew et al (43) studied different reaching movements and ADLs in chronic stroke patients, via the application of FES. The results they obtained showed improvements in range distances, hand opening, an increase in forearm muscle activity, and the ability to complete ADLs in which shoulder flexion was required and in which elbow extension was required and which the patients were initially unable to perform.…”

“…In stroke subjects, the application of electrostimulation to the muscles of the UL has been found to enhance the reacquisition of motor skills with the affected UL and to increase the degree of shoulder flexion and elbow extension, thus assisting the reaching movement, as measured with motion analysis systems; our results confirm and extend these previous works ( 42 – 44 ) by demonstrating that FES applied to the UL muscles is effective for improving simple single joint movements as well as more complex reach-to-grasp movements performed with the hemiparetic UL. Makowski et al ( 42 ) and Lew et al ( 43 ) studied different reaching movements and ADLs in chronic stroke patients, via the application of FES. The results they obtained showed improvements in range distances, hand opening, an increase in forearm muscle activity, and the ability to complete ADLs in which shoulder flexion was required and in which elbow extension was required and which the patients were initially unable to perform.…”

Prediction of setup times for an advanced upper limb functional electrical stimulation system

“…In order to align with principles known to drive functional recovery, notably the need to intensively practise a variety of challenging, functional tasks, 3,4 and offer sufficient flexibility to accommodate a broad range of patients, FES devices are becoming increasingly sophisticated. These advanced FES devices have multiple channels, are usually controlled via sensors, provide some form of biofeedback and may incorporate electrode arrays 2,5 Although largely unreported, an unintended consequence of this increase in complexity is likely to have been an increase in setup time of some of these devices. For instance, systems that include a brain interface require calibration of the interface, and some of the recent upper limb systems based on iterative learning control rely on person-specific dynamic model identification.…”

Combining Mental Training and Physical Training With Goal-Oriented Protocols in Stroke Rehabilitation: A Feasibility Case Study

“…For example, we can design our training platform fully via functional electrical stimulation. However, Lew et al reported that not all individuals with chronic stroke are able to use an FES unit for elbow position control (Lew et al, 2016 ). Therefore, we did not use a full FES design in this study.…”