Home-based self-help telerehabilitation of the upper limb assisted by an electromyography-driven wrist/hand exoneuromusculoskeleton after stroke

Abstract

Background: Most stroke survivors have sustained upper limb impairment in their distal joints. An electromyography (EMG)-driven wrist/hand exoneuromusculoskeleton (WH-ENMS) was developed previously. The present study investigated the feasibility of a home-based self-help telerehabilitation program assisted by the aforementioned EMG-driven WH-ENMS and its rehabilitation effects after stroke.

Methods: Persons with chronic stroke (n = 11) were recruited in a single-group trial. The training progress, including the training frequency and duration, was telemonitored. The clinical outcomes were evaluated using the Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), Wolf Motor Function Test (WMFT), Motor Functional Independence Measure (FIM), and Modified Ashworth Scale (MAS). Improvement in muscle coordination was investigated in terms of the EMG activation level and the Co-contraction Index (CI) of the target muscles, including the abductor pollicis brevis (APB), flexor carpi radialis-flexor digitorum (FCR-FD), extensor carpi ulnaris-extensor digitorum (ECU-ED), biceps brachii (BIC), and triceps brachii (TRI). The movement smoothness and compensatory trunk movement were evaluated in terms of the following two kinematic parameters: number of movement units (NMUs) and maximal trunk displacement (MTD). The above evaluations were conducted before and after the training.

Results: All of the participants completed the home-based program with an intensity of 63.0 ± 1.90 (mean ± SD) min/session and 3.73 ± 0.75 (mean ± SD) sessions/week. After the training, motor improvements in the entire upper limb were found, as indicated by the significant improvements (P < 0.05) in the FMA, ARAT, WMFT, and MAS; significant decreases (P < 0.05) in the EMG activation levels of the APB and FCR-FD; significant decreases (P < 0.05) in the CI of the ECU-ED/FCR-FD, ECU-ED/BIC, FCR-FD/APB, FCR-FD/BIC, FCR-FD/TRI, APB/BIC and BIC/TRI muscle pairs; and significant reductions (P < 0.05) in the NMUs and MTD.

Conclusions: The results suggested that the home-based self-help telerehabilitation program assisted by EMG-driven WH-ENMS is feasible and effective for improving the motor function of the paretic upper limb after stroke. Trial registration ClinicalTrials.gov. NCT03752775; Date of registration: November 20, 2018.

Keywords: Home training; Rehabilitation; Robot; Stroke; Telerehabilitation.

Fig. 1

Experimental and training set up of the EMG-driven WH-ENMS. a Photograph of the EMG-driven WH-ENMS and b the screen captures of the interface. The training set up in a session assisted by the EMG-driven WH-ENMS and configuration of c the horizontal task and d vertical task

Fig. 2

The Consolidated Standards of Reporting Trials flowchart of the experimental design

Fig. 3

Pre-training tutorial procedure

Fig. 4

Timeline of the EMG-driven WH-ENMS-assisted home-based self-help upper limb training program

Fig. 5

Configuration of EMG recording during the bare arm test

Fig. 6

Experimental setup for a the horizontal task and b vertical task during three-dimensional motion capturing

Fig. 7

The measured clinical scores of the a FMA, ARAT, WMFT and FIM, and b the MAS before (Pre) and after (Post) the training represented by means and standard errors. Significance levels are indicated by * (P ≤ 0.05), ** (P ≤ 0.01), and *** (P ≤ 0.001)

Fig. 8

a EMG activation levels of the APB and FCR–FD during the bare hand evaluations, and b the EMG CI between the FCR–FD and ECU–ED, ECU–ED and BIC, FCR–FD and APB, FCR–FD and BIC, FCR–FD and TRI, APB and BIC, and BIC and TRI during the bare hand evaluations before (Pre) and after (Post) the training represented by means and standard errors. Significance levels are indicated by * (P ≤ 0.05), ** (P ≤ 0.01), and *** (P ≤ 0.001)

Fig. 9

Representative measured trajectory of the hand marker during the transport phases in a the horizontal task and b vertical task for a participant, and the related velocity profiles of the trial before and after training. c The NMUs before (Pre) and after (Post) the training represented in terms of the mean and standard error. Significance levels are indicated by *** (P ≤ 0.001)

Fig. 10

Representative measured trajectory of the thorax marker over the entire trial for a the horizontal task and b vertical task for a participant, and the related displacement profiles in the trial before and after the training. c The MTD before (Pre) and after (Post) the training represented in terms of the mean and standard error. Significance levels are indicated by * (P ≤ 0.05)