Robotic Exoskeleton Gait Training in Stroke: An Electromyography-Based Evaluation

Perceptions of using exoskeleton technology among physiotherapists and stroke survivors in Malaysia: a mixed methods study

Exoskeleton technology has the potential to enhance the functional abilities of individuals with upper or lower limb dysfunction, including stroke survivors. However, its adoption in Malaysia has been limited due to its restricted availability in rehabilitation centres and hospitals. In this study, we aim to explore the perceptions and opinions of physiotherapists and stroke survivors regarding exoskeleton technology, focusing on identifying desired design features and investigating their views on its use in rehabilitation. An online survey was conducted to assess the preferred features of exoskeleton technology among physiotherapists and stroke survivors. Subsequently, one-to-one online in-depth interviews were carried out with physiotherapists who had experience using exoskeleton technology. Data were analysed using descriptive, thematic, and triangulation analysis methods. The analysis included 81 survey questionnaires from physiotherapists and 122 from stroke survivors. Both groups highlighted cost-effectiveness, safety, comfort, and ease of use as key features of exoskeletons. Additional insights from in-depth interviews with five physiotherapists emphasized the importance of a user-friendly interface, adjustability, and a lightweight design. Physiotherapists also expressed that exoskeleton technology could reduce their workload, minimize musculoskeletal-related disorders, and enhance their confidence. The main desired features identified by both physiotherapists and stroke survivors for exoskeleton technology include cost-effectiveness, safety, comfort, and ease of use. Physiotherapists further viewed it as a valuable tool to alleviate their workload and reduce musculoskeletal-related disorders while boosting confidence. These findings offer valuable guidance to developers, engineers, and manufacturers in the country, aiding in the development of client-centred exoskeleton features.

Hands-free Atalante exoskeleton in post-stroke gait and balance rehabilitation: a safety study

BACKGROUND

Stroke often results in gait dysfunction, impairing daily activities and quality of life. Overground robotic exoskeletons hold promise for post-stroke rehabilitation. This study primarily aimed to assess the safety of hands-free Atalante exoskeleton training in post-stroke subjects, with a secondary aim to assess gait and balance.

METHODS

Forty subjects (10.2 ± 12.1 months post-stroke) with gait dysfunction (Functional Ambulation Category [FAC] score ≤ 3) underwent five training sessions over three weeks with a hands-free exoskeleton (Atalante, Wandercraft, France). Safety, the primary outcome, was evaluated by the number and severity of adverse events (AEs), judged by an independent clinical evaluation committee (CEC). A usability test was performed during the fifth training session followed by the exoskeleton use questionnaire. Gait and balance were assessed pre/post-training via walking capacity score (FAC), gait speed by 10-meter walk test (10MWT), walked distance by 6-minute walk test (6MWT), and balance by Berg Balance Scale (BBS). Spasticity was assessed with the Modified Ashworth scale. Anxiety and depression were quantified using the Hospital Anxiety and Depression Scale. Safety outcomes were analyzed using the Wilson, Lee and Dubin methods for proportions, and occurrence rates were computed. Within-group differences were compared using Wilcoxon, McNemar, and Friedman tests, with significance set at P < 0.05.

RESULTS

Thirty-one subjects completed the training sessions, while nine discontinued. The study reported two serious adverse events (SAE) (vertigo, dysarthria) and six AEs, with the CEC concluding that no SAE was linked to the device/study procedure. The average AE rate per session was 2.5 ± 1.4%, including four events possibly linked to the device/study procedure (knee pain [n = 1], skin lacerations [n = 3]), classified as negligible or minor by the CEC. A high proportion (82.6%) successfully completed the usability test and reported satisfaction (90%) on the exoskeleton use questionnaire. For gait and balance, favorable changes were observed in FAC, 10MWT, 6MWT, and BBS scores Post-training (p < 0.05, respectively). Spasticity, anxiety, and depression remained unchanged.

CONCLUSIONS

This study indicates that the hands-free Atalante exoskeleton is safe, feasible, and well-tolerated for gait and balance rehabilitation in post-stroke subjects, warranting larger randomized controlled trials to assess its efficacy.

TRIAL REGISTRATION

Evaluation of the Use of the Atalante Exoskeleton in Patients Presenting an Hemiplegia Due to Cerebrovascular Accident (INSPIRE) trial was registered at ClinicalTrials.gov (NCT04694001, registered on 20201231).

Effects of robot-assisted gait training on trunk symmetry improvement in patients with chronic hemiplegia: A randomized, single-blind clinical trial

BACKGROUND

Stroke-induced gait impairments often result in asymmetrical trunk alignment, affecting mobility and quality of life of patients. This randomized, single-blind clinical trial investigated the efficacy of robot-assisted gait training in addressing this issue and explored its impact on lower limb functions.

METHODS

Fifty patients with chronic stroke were included in this study, with one group receiving traditional rehabilitation therapy and the other receiving additional robot-assisted gait training session. Participants in the robot-assisted gait training (RAGT) group underwent 30-min session, thrice per week for 4 weeks, totaling 12 sessions, in addition to traditional rehabilitation therapy. All participants underwent preintervention assessments, with reassessments at 2 and 4 weeks after the intervention. We assessed trunk symmetry and gait parameters, including step time, step length, separation line, and foot force, along with knee joint extensor muscle strength and stiffness.

FINDINGS

Significant improvements in trunk symmetry were observed in the RAGT group (F(2,46) = 35.52, p < 0.001, η2 = 0.607). Changes in step length asymmetry were significant for both groups (p < 0.000 each) without intergroup differences, whereas paralyzed knee extensor strength showed greater improvement in the RAGT group (p < 0.001).

INTERPRETATION

The study findings revealed significant improvements in trunk symmetry and muscle strength among patients receiving RAGT. These results underscore the promising role of RAGT in stroke rehabilitation. Thus, proper gait patterns may contribute to maintaining a healthy posture.

The Effectiveness of Overground Robot Exoskeleton Gait Training on Gait Outcomes, Balance, and Motor Function in Patients with Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

This study aimed to investigate the effects of overground robot exoskeleton gait training on gait outcomes, balance, and motor function in patients with stroke.

METHODS

Following the PRISMA guidelines, literature searches were performed in the PubMed, EMBASE, Cochrane Central Register of Controlled Trials, SCOPUS, Ovid-LWW, and RISS databases. A total of 504 articles were identified, of which 19 were included for analysis after application of the inclusion and exclusion criteria. The included literature was qualitatively evaluated using the PEDro scale, while the Egger's regression, funnel plot, and trim-and-fill methods were applied to assess and adjust for publication bias.

RESULTS

The averaged PEDro score was 6.21 points, indicating a high level of methodological quality. In the analysis based on dependent variables, higher effect sizes were observed in the following ascending order: gait speed (g = 0.26), motor function (g = 0.21), gait ability (g = 0.18), Timed Up and Go Test (g = -0.15), gait endurance (g = 0.11), and Berg Balance Scale (g = 0.05). Subgroup analyses further revealed significant differences in Asian populations (g = 0.26), sessions lasting longer than 30 min (g = 0.37), training frequency of three times per week or less (g = 0.38), and training duration of four weeks or less (g = 0.25). Overall, the results of this study indicate that overground robot exoskeleton gait training is effective at improving gait speed in patients with stroke, particularly when the sessions exceed 30 min, are conducted three times or less per week, and last for four weeks or less.

CONCLUSION

our results suggest that training is an effective intervention for patients with stroke, provided that appropriate goal-setting and intensity and overground robot exoskeleton gait are applied.

A State-of-the-Art of Exoskeletons in Line with the WHO's Vision on Healthy Aging: From Rehabilitation of Intrinsic Capacities to Augmentation of Functional Abilities

The global aging population faces significant health challenges, including an increasing vulnerability to disability due to natural aging processes. Wearable lower limb exoskeletons (LLEs) have emerged as a promising solution to enhance physical function in older individuals. This systematic review synthesizes the use of LLEs in alignment with the WHO's healthy aging vision, examining their impact on intrinsic capacities and functional abilities. We conducted a comprehensive literature search in six databases, yielding 36 relevant articles covering older adults (65+) with various health conditions, including sarcopenia, stroke, Parkinson's Disease, osteoarthritis, and more. The interventions, spanning one to forty sessions, utilized a range of LLE technologies such as Ekso®, HAL®, Stride Management Assist®, Honda Walking Assist®, Lokomat®, Walkbot®, Healbot®, Keeogo Rehab®, EX1®, overground wearable exoskeletons, Eksoband®, powered ankle-foot orthoses, HAL® lumbar type, Human Body Posturizer®, Gait Enhancing and Motivation System®, soft robotic suits, and active pelvis orthoses. The findings revealed substantial positive outcomes across diverse health conditions. LLE training led to improvements in key performance indicators, such as the 10 Meter Walk Test, Five Times Sit-to-Stand test, Timed Up and Go test, and more. Additionally, enhancements were observed in gait quality, joint mobility, muscle strength, and balance. These improvements were accompanied by reductions in sedentary behavior, pain perception, muscle exertion, and metabolic cost while walking. While longer intervention durations can aid in the rehabilitation of intrinsic capacities, even the instantaneous augmentation of functional abilities can be observed in a single session. In summary, this review demonstrates consistent and significant enhancements in critical parameters across a broad spectrum of health conditions following LLE interventions in older adults. These findings underscore the potential of LLE in promoting healthy aging and enhancing the well-being of older adults.

End-effector lower limb robot-assisted gait training effects in subacute stroke patients: A randomized controlled pilot trial

BACKGROUND

This pilot study investigated end-effector lower limb rehabilitation robot training effects in subacute stroke patients.

METHODS

Forty-nine stroke patients were randomly assigned to 2 treatment groups: a 30-minute end-effector lower limb rehabilitation robot training plus 1.5-hour conventional physiotherapy (robot group; n = 26), or a 2-hour conventional physiotherapy (control group; n = 23). All patients received 5 treatments weekly for 4 weeks. The functional ambulatory category was the primary outcome and the motricity index, Fugl Meyer assessment-lower extremity, rivermead mobility index, 10 meter walk test, Berg balance scale, and modified Barthel index were secondary outcomes.

RESULTS

All outcome measures significantly improved in both groups after training (P > .05). The robot group improved more in FAC than the control group (P = .005).

CONCLUSIONS

Compared with conventional physiotherapy alone, end-effector lower limb robot-assisted gait training with conventional physiotherapy improved subacute stroke patients walking ability.

Overground Robotic Exoskeleton Training for Patients With Stroke on Walking-Related Outcomes: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This review aims to evaluate the effectiveness of solely overground robotic exoskeleton (RE) training or overground RE training with conventional rehabilitation in improving walking ability, speed, and endurance among patients with stroke.

DATA SOURCES

Nine databases, 5 trial registries, gray literature, specified journals, and reference lists from inception until December 27, 2021.

STUDY SELECTION

Randomized controlled trials adopting overground robotic exoskeleton training for patients with any phases of stroke on walking-related outcomes were included.

DATA EXTRACTION

Two independent reviewers extracted items and performed risk of bias using the Cochrane Risk of Bias tool 1 and certainty of evidence using the Grades of Recommendation Assessment, Development, and Evaluation.

DATA SYNTHESIS

Twenty trials involving 758 participants across 11 countries were included in this review. The overall effect of overground robotic exoskeletons on walking ability at postintervention (d=0.21; 95% confidence interval [CI], 0.01, 0.42; Z=2.02; P=.04) and follow-up (d=0.37; 95% CI, 0.03, 0.71; Z=2.12; P=.03) and walking speed at postintervention (d=0.23; 95% CI, 0.01, 0.46; Z=2.01; P=.04) showed significant improvement compared with conventional rehabilitation. Subgroup analyses suggested that RE training should combine with conventional rehabilitation. A preferable gait training regime is <4 times per week over ≥6 weeks for ≤30 minutes per session among patients with chronic stroke and ambulatory status of independent walkers before training. Meta-regression did not identify any effect of the covariates on the treatment effect. The majority of randomized controlled trials had small sample sizes, and the certainty of the evidence was very low.

CONCLUSION

Overground RE training may have a beneficial effect on walking ability and walking speed to complement conventional rehabilitation. Further large-scale and long-term, high-quality trials are recommended to enhance the quality of overground RE training and confirm its sustainability.

Tapping Into Skeletal Muscle Biomechanics for Design and Control of Lower Limb Exoskeletons: A Narrative Review

Lower limb exoskeletons and exosuits ("exos") are traditionally designed with a strong focus on mechatronics and actuation, whereas the "human side" is often disregarded or minimally modeled. Muscle biomechanics principles and skeletal muscle response to robot-delivered loads should be incorporated in design/control of exos. In this narrative review, we summarize the advances in literature with respect to the fusion of muscle biomechanics and lower limb exoskeletons. We report methods to measure muscle biomechanics directly and indirectly and summarize the studies that have incorporated muscle measures for improved design and control of intuitive lower limb exos. Finally, we delve into articles that have studied how the human-exo interaction influences muscle biomechanics during locomotion. To support neurorehabilitation and facilitate everyday use of wearable assistive technologies, we believe that future studies should investigate and predict how exoskeleton assistance strategies would structurally remodel skeletal muscle over time. Real-time mapping of the neuromechanical origin and generation of muscle force resulting in joint torques should be combined with musculoskeletal models to address time-varying parameters such as adaptation to exos and fatigue. Development of smarter predictive controllers that steer rather than assist biological components could result in a synchronized human-machine system that optimizes the biological and electromechanical performance of the combined system.

Exoskeleton Training Modulates Complexity in Movement Patterns and Cortical Activity in Able-Bodied Volunteers

Robot-aided gait training (RAGT) plays a crucial role in providing high-dose and high-intensity task-oriented physical therapy. The human-robot interaction during RAGT remains technically challenging. To achieve this aim, it is necessary to quantify how RAGT impacts brain activity and motor learning. This work quantifies the neuromuscular effect induced by a single RAGT session in healthy middle-aged individuals. Electromyographic (EMG) and motion (IMU) data were recorded and processed during walking trials before and after RAGT. Electroencephalographic (EEG) data were recorded during rest before and after the entire walking session. Linear and nonlinear analyses detected changes in the walking pattern, paralleled by a modulation of cortical activity in the motor, attentive, and visual cortices immediately after RAGT. Increases in alpha and beta EEG spectral power and pattern regularity of the EEG match the increased regularity of body oscillations in the frontal plane, and the loss of alternating muscle activation during the gait cycle, when walking after a RAGT session. These preliminary results improve the understanding of human-machine interaction mechanisms and motor learning and may contribute to more efficient exoskeleton development for assisted walking.

Randomized Controlled Trial of Robot-Assisted Gait Training versus Therapist-Assisted Treadmill Gait Training as Add-on Therapy in Early Subacute Stroke Patients: The GAITFAST Study Protocol

The GAITFAST study (gait recovery in patients after acute ischemic stroke) aims to compare the effects of treadmill-based robot-assisted gait training (RTGT) and therapist-assisted treadmill gait training (TTGT) added to conventional physical therapy in first-ever ischemic stroke patients. GAITFAST (Clinicaltrials.gov identifier: NCT04824482) was designed as a single-blind single-center prospective randomized clinical trial with two parallel groups and a primary endpoint of gait speed recovery up to 6 months after ischemic stroke. A total of 120 eligible and enrolled participants will be randomly allocated (1:1) in TTGT or RTGT. All enrolled patients will undergo a 2-week intensive inpatient rehabilitation including TTGT or RTGT followed by four clinical assessments (at the beginning of inpatient rehabilitation 8-15 days after stroke onset, after 2 weeks, and 3 and 6 months after the first assessment). Every clinical assessment will include the assessment of gait speed and walking dependency, fMRI activation measures, neurological and sensorimotor impairments, and gait biomechanics. In a random selection (1:2) of the 120 enrolled patients, multimodal magnetic resonance imaging (MRI) data will be acquired and analyzed. This study will provide insight into the mechanisms behind poststroke gait behavioral changes resulting from intensive rehabilitation including assisted gait training (RTGT or TTGT) in early subacute IS patients.

A unified scheme for the benchmarking of upper limb functions in neurological disorders

BACKGROUND

In neurorehabilitation, we are witnessing a growing awareness of the importance of standardized quantitative assessment of limb functions. Detailed assessments of the sensorimotor deficits following neurological disorders are crucial. So far, this assessment has relied mainly on clinical scales, which showed several drawbacks. Different technologies could provide more objective and repeatable measurements. However, the current literature lacks practical guidelines for this purpose. Nowadays, the integration of available metrics, protocols, and algorithms into one harmonized benchmarking ecosystem for clinical and research practice is necessary.

METHODS

This work presents a benchmarking framework for upper limb capacity. The scheme resulted from a multidisciplinary and iterative discussion among several partners with previous experience in benchmarking methodology, robotics, and clinical neurorehabilitation. We merged previous knowledge in benchmarking methodologies for human locomotion and direct clinical and engineering experience in upper limb rehabilitation. The scheme was designed to enable an instrumented evaluation of arm capacity and to assess the effectiveness of rehabilitative interventions with high reproducibility and resolution. It includes four elements: (1) a taxonomy for motor skills and abilities, (2) a list of performance indicators, (3) a list of required sensor modalities, and (4) a set of reproducible experimental protocols.

RESULTS

We proposed six motor primitives as building blocks of most upper-limb daily-life activities and combined them into a set of functional motor skills. We identified the main aspects to be considered during clinical evaluation, and grouped them into ten motor abilities categories. For each ability, we proposed a set of performance indicators to quantify the proposed ability on a quantitative and high-resolution scale. Finally, we defined the procedures to be followed to perform the benchmarking assessment in a reproducible and reliable way, including the definition of the kinematic models and the target muscles.

CONCLUSIONS

This work represents the first unified scheme for the benchmarking of upper limb capacity. To reach a consensus, this scheme should be validated with real experiments across clinical conditions and motor skills. This validation phase is expected to create a shared database of human performance, necessary to have realistic comparisons of treatments and drive the development of new personalized technologies.

Measurement, Evaluation, and Control of Active Intelligent Gait Training Systems—Analysis of the Current State of the Art

Gait recognition and rehabilitation has been a research hotspot in recent years due to its importance to medical care and elderly care. Active intelligent rehabilitation and assistance systems for lower limbs integrates mechanical design, sensing technology, intelligent control, and robotics technology, and is one of the effective ways to resolve the above problems. In this review, crucial technologies and typical prototypes of active intelligent rehabilitation and assistance systems for gait training are introduced. The limitations, challenges, and future directions in terms of gait measurement and intention recognition, gait rehabilitation evaluation, and gait training control strategies are discussed. To address the core problems of the sensing, evaluation and control technology of the active intelligent gait training systems, the possible future research directions are proposed. Firstly, different sensing methods need to be proposed for the decoding of human movement intention. Secondly, the human walking ability evaluation models will be developed by integrating the clinical knowledge and lower limb movement data. Lastly, the personalized gait training strategy for collaborative control of human–machine systems needs to be implemented in the clinical applications.