Passive Robots for Stroke Rehabilitation: A Feasibility Study

About 800,000 individuals suffer from a stroke every year in the United States. The majority of stroke survivors often experience lingering deficits in upper extremity function. High-end robotic devices can improve outcomes and clinical productivity; however, these devices are expensive and bulky, making them not practical for many clinical or home environments. This study aims to evaluate the feasibility of low-cost non-motorized devices for stroke rehabilitation in a long-term intervention. The intervention will involve training with a table-top, semi-passive (i.e., no motors) exercise equipment called SepaRRo and commonly-used neuromuscular stimulation. The stimulation will be provided during functional activities using a custom controller (NeuRRoFES) to trigger stimulation. These instruments are designed to provide flexible, compliant assistance/resistance to improve upper extremity function and can be used in a home setting. The study will measure technical feasibility (e.g., qualitative survey, adherence, time on task, retention, ability to perform tasks) as well as clinical feasibility (i.e., changes in biomechanical, neurophysiological, and functional measures) of an intervention with these devices in stroke survivors. The findings aim to support the development of affordable, home-use rehabilitation systems for stroke patients.

Participants will receive upper extremity rehabilitation using SepaRRo and NeuRRoFES 2-5 times per week for 2-6 weeks

Device: Functional Training with SepaRRo and NeuRRoFES

Participants will perform functional movements (e.g., reach for targets) with their extremities. During movements, the devices will be used to assist or resist their motion. Participants may receive biofeedback of their movements to better engage them in training. Participants may receive assistance from the devices (including neuromuscular stimulation) and/or their less-impaired limb.

Plazo: Post-intervention (immediately following last session of intervention)

Subjective feedback regarding feasibility of the device for training

Plazo: Post-intervention (immediately following last session of intervention)

Measure of how many participants completed intervention

Plazo: Post-intervention (immediately following last session of intervention)

Measure of percentage of sessions completed

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively.

Changes in upper extremity Fugl-Meyer score from before the intervention (from baseline) to after its completion using publicly available scoring sheets. The Fugl-Meyer score is a measure of functional impairment and runs from 0 to 66 points, with higher numbers reflecting better outcome.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in reachable workspace from before the intervention (from baseline) to after its completion). The reachable workspace area will be measured with SepaRRo obtained from optical encoders mounted in the device.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in voluntary ability to open the hand from before the intervention (from baseline to after its completion). Voluntary hand opening will be measured with motion capture equipment.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in the Action Research Arm Test Score from before the intervention (from baseline) to after its completion using publicly available scoring sheets. The Action Research Arm Test is a measure of arm functional ability and runs from 0 to 57 points, with higher numbers reflecting better outcome.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in functional measure of arm disability (BBT) from before the intervention (from baseline) to after its completion using publicly available scoring sheets.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in force produced by the hand from before the intervention (from baseline) to after its completion as measured by force production recorded with a dynamometer

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in force produced by the arm from before the intervention (from baseline) to after its completion as measured by force production recorded with a dynamometer

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in muscle coordination of the upper extremity muscles as measured using surface electromyography between before the intervention (from baseline) to after its completion.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in coordination of the upper extremity joints as measured motion capture between before the intervention (from baseline) to after its completion.

Plazo: Baseline and post-intervention measurements will be taken on separate days, within a week of the first and last sessions of the intervention, respectively

Changes in corticospinal excitability of the upper extremity muscles as measured using surface electromyography and transcranial magnetic stimulation between before the intervention (from baseline) to after its completion

Passive Robots for Stroke Rehabilitation