Feasibility study of a take-home array-based functional electrical stimulation system with automated setup for current functional electrical stimulation users with foot-drop

Usability of Functional Electrical Stimulation in Upper Limb Rehabilitation in Post-Stroke Patients: A Narrative Review

Stroke leads to significant impairment in upper limb (UL) function. The goal of rehabilitation is the reestablishment of pre-stroke motor stroke skills by stimulating neuroplasticity. Among several rehabilitation approaches, functional electrical stimulation (FES) is highlighted in stroke rehabilitation guidelines as a supplementary therapy alongside the standard care modalities. The aim of this study is to present a comprehensive review regarding the usability of FES in post-stroke UL rehabilitation. Specifically, the factors related to UL rehabilitation that should be considered in FES usability, as well a critical review of the outcomes used to assess FES usability, are presented. This review reinforces the FES as a promising tool to induce neuroplastic modifications in post-stroke rehabilitation by enabling the possibility of delivering intensive periods of treatment with comparatively less demand on human resources. However, the lack of studies evaluating FES usability through motor control outcomes, specifically movement quality indicators, combined with user satisfaction limits the definition of FES optimal therapeutical window for different UL functional tasks. FES systems capable of integrating postural control muscles involving other anatomic regions, such as the trunk, during reaching tasks are required to improve UL function in post-stroke patients.

Effect of functional electrical stimulation on postural control in children with hemiplegic cerebral palsy: a randomized controlled trial

Background

Children with cerebral palsy have impairments of postural control during static and dynamic activities. Improving postural control is one of the primary objectives of rehabilitation for children with cerebral palsy. Therefore, the objective of this study was to study the effect of functional electric stimulation on postural control in children with hemiplegic cerebral palsy. A randomized controlled study was conducted on 30 children with hemiplegic cerebral palsy (18 boys and 12 girls) between the ages of 8 and 12 years. The children were distributed in two equal groups. The experimental group received functional electrical stimulation (pulse width 300 μs, frequency 33 Hz, 2 h/day, 3 days/week, / 3 consecutive months) in addition to the traditional physical therapy program. While the control group received the traditional physiotherapy program only for the same duration. The outcomes included postural stability indices that were measured at baseline and following 3 months of intervention using the Biodex balance system.

Results

A significant improvement was found in the postural stability indices of children in both groups, comparing their mean values before and after treatment. Furthermore, the results revealed a greater improvement in the postural stability of the experimental group (P < 0.001).

Conclusion

Functional electrical stimulation may be a useful tool to enhance the postural stability of children with hemiplegic cerebral palsy.

Clinical trial registration

This study was registered in the ClinicalTrial.gov PRS (NCT04269798). https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S0009LHP&selectaction=Edit&uid=U0003GAI&ts=4&cx=74k74l

Clinical outcome measures to evaluate the effects of orthotic management post-stroke: a systematic review

PURPOSE

To identify, and classify, according to International Classification of Functioning, Disability and Health (ICF), clinically applicable outcome measures that have been used to evaluate lower limb orthotic management post-stroke and to investigate which outcome measures recorded the largest effect sizes.

MATERIALS AND METHODS

Electronic searches were performed in Pubmed, Cochrane, Web of Science, Cinahl, Scopus and Embase databases from inception to May 2020. Articles were included if they investigated clinical outcomes in people post-stroke who had received a lower-limb orthotic intervention.

RESULTS

88 articles underwent full-text review and 54 were included in the review, which was performed in accordance with the Preferred Reporting Items for Systematic Review (PRISMA) principles. 48 different outcome measures were identified; effect sizes were able to be calculated from 39 studies. The most frequently applied outcome measures were the 10-metre Walk Test and the timed-up-and-go test. Outcome measures that recorded large effect sizes in two or more studies were the 10-metre Walk Test, Functional Reach Test, and Physiological Cost Index. When coded according to the ICF, the most frequently represented codes were d450 (Walking) and d455 (moving around).

CONCLUSIONS

Results suggest that outcome measures related to mobility (ICF chapter d4) are most often applied to evaluate orthotic management post-stroke. Effect sizes appear to be greatest in outcome measures related to velocity, balance, and energy expenditure.IMPLICATIONS FOR REHABILITATIONThe 10-meter Walk Test appears to have the greatest effect size when evaluating orthotic management post-stroke.While outcome measures related to mobility are commonly applied when evaluating orthotic management post-stroke, rehabilitation professionals should consider complementing these with measures representing the participation domain of the ICF.

Caregiver Delivered Sensory Electrical Stimulation for Post Stroke Upper Limb Spasticity: A Single Blind Crossover Randomized Feasibility Study

We developed a 64 channel sensory electrical stimulator which delivers a dynamic and variable ‘Sensory Barrage’ Stimulation (SBS). Our aim was to assess the feasibility of caregivers delivering the stimulation in the community for a clinical trial comparing single channel Transcutaneous Electrical Nerve Stimulation (TENS) with SBS for post stroke upper limb spasticity. We trained caregivers of 16 participants with post stroke upper limb spasticity to sequentially administer SBS and TENS for 60 min daily for four weeks each, with a washout period of two weeks in between. Outcome measures tested were recruitment and retention rates, compliance with interventions and daily recording of Participant -reported Numerical Rating Scale (NRS). We also collected results of Action Research Arm Test (ARAT), Leeds Arm Spasticity Impact Scale (LASIS) and Modified Ashworth Scale (MAS) for spasticity. Out of 21 potential participants, 16 consented and 15 completed the protocol. Ten participants received TENS for 80% (23/28) of the intended hours. Eleven participants completed NRS for at 80% (45/56) of the study days. All participants attended all visits. The MAS reduced by at least one in five participants after SBS and in three after TENS. Minimal Clinically Important Difference (MCID) of four points increase in ARAT was seen in five participants following TENS, and in four following SBS. A MCID of 18% decrease in NRS was reported by eight participants after TENS and three after SBS. This study demonstrated the feasibility of undertaking a trial of sensory electrical stimulation for post-stroke spasticity with caregivers delivering intervention in community. The study was not powered to detect efficacy of the interventions. Trial registration number: NCT02907775.Date 20-9-2016.

Advances in neuroprosthetic management of foot drop: a review

This paper reviews the technological advances and clinical results obtained in the neuroprosthetic management of foot drop. Functional electrical stimulation has been widely applied owing to its corrective abilities in patients suffering from a stroke, multiple sclerosis, or spinal cord injury among other pathologies. This review aims at identifying the progress made in this area over the last two decades, addressing two main questions: What is the status of neuroprosthetic technology in terms of architecture, sensorization, and control algorithms?. What is the current evidence on its functional and clinical efficacy? The results reveal the importance of systems capable of self-adjustment and the need for closed-loop control systems to adequately modulate assistance in individual conditions. Other advanced strategies, such as combining variable and constant frequency pulses, could also play an important role in reducing fatigue and obtaining better therapeutic results. The field not only would benefit from a deeper understanding of the kinematic, kinetic and neuromuscular implications and effects of more promising assistance strategies, but also there is a clear lack of long-term clinical studies addressing the therapeutic potential of these systems. This review paper provides an overview of current system design and control architectures choices with regard to their clinical effectiveness. Shortcomings and recommendations for future directions are identified.

Home FES: An Exploratory Review

This review of literature focuses on the multiple uses of Functional Electrical Stimulation (FES) and how this modality may be a valuable home-based therapy. Papers pertaining to home FES exercise were collected using the Web of Science, Google Scholar databases and collegial hints. In our opinion, the following statements summarize the results. FES may be used to induce health benefits in populations with paralysis, and in persons with musculoskeletal, cardiorespiratory and renal pathology. The EU Project Rise showed how FES could have a variety of encouraging outcomes for patients with denervated muscles following traumatic injuries. As suggested by recent literature, FES has proven to be a viable form of exercise for elderly individuals. Thus, Home FES may be an option for patients looking for an additional form of muscle and cardiopulmonary physical therapy.

A foot drop compensation device based on surface multi-field functional electrical stimulation-Usability study in a clinical environment

Introduction

Functional electrical stimulation applies electrical pulses to the peripheral nerves to artificially achieve a sensory/motor function. When applied for the compensation of foot drop it provides both assistive and therapeutic effects. Multi-field electrodes have shown great potential but may increase the complexity of these systems. Usability aspects should be checked to ensure their success in clinical environments.

Methods

We developed the Fesia Walk device, based on a surface multi-field electrode and an automatic calibration algorithm, and carried out a usability study to check the feasibility of integrating this device in therapeutic programs in clinical environments. The study included 4 therapists and 10 acquired brain injury subjects (8 stroke and 2 traumatic brain injury).

Results

Therapists and users were “very satisfied” with the device according to the Quebec User Evaluation of Satisfaction with Assistive Technology scale, with average scores of 4.1 and 4.2 out of 5, respectively. Therapists considered the Fesia Walk device as “excellent” according to the System Usability Scale with an average score of 85.6 out of 100.

Conclusions

This study showed us that it is feasible to include surface multi-field technology while keeping a device simple and intuitive for successful integration in common neurorehabilitation programs.

The use of advanced medical technologies at home: a systematic review of the literature

Background

The number of medical technologies used in home settings has increased substantially over the last 10–15 years. In order to manage their use and to guarantee quality and safety, data on usage trends and practical experiences are important. This paper presents a literature review on types, trends and experiences with the use of advanced medical technologies at home.

Methods

The study focused on advanced medical technologies that are part of the technical nursing process and ‘hands on’ processes by nurses, excluding information technology such as domotica. The systematic review of literature was performed by searching the databases MEDLINE, Scopus and Cinahl. We included papers from 2000 to 2015 and selected articles containing empirical material.

Results

The review identified 87 relevant articles, 62% was published in the period 2011–2015. Of the included studies, 45% considered devices for respiratory support, 39% devices for dialysis and 29% devices for oxygen therapy. Most research has been conducted on the topic ‘user experiences’ (36%), mainly regarding patients or informal caregivers. Results show that nurses have a key role in supporting patients and family caregivers in the process of homecare with advanced medical technologies and in providing information for, and as a member of multi-disciplinary teams. However, relatively low numbers of articles were found studying nurses perspective.

Conclusions

Research on medical technologies used at home has increased considerably until 2015. Much is already known on topics, such as user experiences; safety, risks, incidents and complications; and design and technological development. We also identified a lack of research exploring the views of nurses with regard to medical technologies for homecare, such as user experiences of nurses with different technologies, training, instruction and education of nurses and human factors by nurses in risk management and patient safety.

A decision support system for electrode shaping in multi-pad FES foot drop correction

BACKGROUND

Functional electrical stimulation (FES) can be applied as an assistive and therapeutic aid in the rehabilitation of foot drop. Transcutaneous multi-pad electrodes can increase the selectivity of stimulation; however, shaping the stimulation electrode becomes increasingly complex with an increasing number of possible stimulation sites. We described and tested a novel decision support system (DSS) to facilitate the process of multi-pad stimulation electrode shaping. The DSS is part of a system for drop foot treatment that comprises a custom-designed multi-pad electrode, an electrical stimulator, and an inertial measurement unit.

METHODS

The system was tested in ten stroke survivors (3-96 months post stroke) with foot drop over 20 daily sessions. The DSS output suggested stimulation pads and parameters based on muscle twitch responses to short stimulus trains. The DSS ranked combinations of pads and current amplitudes based on a novel measurement of the quality of the induced movement and classified them based on the movement direction (dorsiflexion, plantar flexion, eversion and inversion) of the paretic foot. The efficacy of the DSS in providing satisfactory pad-current amplitude choices for shaping the stimulation electrode was evaluated by trained clinicians. The range of paretic foot motion was used as a quality indicator for the chosen patterns.

RESULTS

The results suggest that the DSS output was highly effective in creating optimized FES patterns. The position and number of pads included showed pronounced inter-patient and inter-session variability; however, zones for inducing dorsiflexion and plantar flexion within the multi-pad electrode were clearly separated. The range of motion achieved with FES was significantly greater than the corresponding active range of motion (p < 0.05) during the first three weeks of therapy.

CONCLUSIONS

The proposed DSS in combination with a custom multi-pad electrode design covering the branches of peroneal and tibial nerves proved to be an effective tool for producing both the dorsiflexion and plantar flexion of a paretic foot. The results support the use of multi-pad electrode technology in combination with automatic electrode shaping algorithms for the rehabilitation of foot drop.

TRIAL REGISTRATION

This study was registered at the Current Controlled Trials website with ClinicalTrials.gov ID NCT02729636 on March 29, 2016.

A review of the design and clinical evaluation of the ShefStim array-based functional electrical stimulation system

Functional electrical stimulation has been shown to be a safe and effective means of correcting foot drop of central neurological origin. Current surface-based devices typically consist of a single channel stimulator, a sensor for determining gait phase and a cuff, within which is housed the anode and cathode. The cuff-mounted electrode design reduces the likelihood of large errors in electrode placement, but the user is still fully responsible for selecting the correct stimulation level each time the system is donned. Researchers have investigated different approaches to automating aspects of setup and/or use, including recent promising work based on iterative learning techniques. This paper reports on the design and clinical evaluation of an electrode array-based FES system for the correction of drop foot, ShefStim. The paper reviews the design process from proof of concept lab-based study, through modelling of the array geometry and interface layer to array search algorithm development. Finally, the paper summarises two clinical studies involving patients with drop foot. The results suggest that the ShefStim system with automated setup produces results which are comparable with clinician setup of conventional systems. Further, the final study demonstrated that patients can use the system without clinical supervision. When used unsupervised, setup time was 14min (9min for automated search plus 5min for donning the equipment), although this figure could be reduced significantly with relatively minor changes to the design.

Motion control of the rabbit ankle joint with a flat interface nerve electrode

INTRODUCTION

A flat interface nerve electrode (FINE) has been shown to improve fascicular and subfascicular selectivity. A recently developed novel control algorithm for FINE was applied to motion control of the rabbit ankle.

METHODS

A 14-contact FINE was placed on the rabbit sciatic nerve (n = 8), and ankle joint motion was controlled for sinusoidal trajectories and filtered random trajectories. To this end, a real-time controller was implemented with a multiple-channel current stimulus isolator.

RESULTS

The performance test results showed good tracking performance of rabbit ankle joint motion for filtered random trajectories and sinusoidal trajectories (0.5 Hz and 1.0 Hz) with <10% average root-mean-square (RMS) tracking error, whereas the average range of ankle joint motion was between -20.0 ± 9.3° and 18.1 ± 8.8°.

CONCLUSIONS

The proposed control algorithm enables the use of a multiple-contact nerve electrode for motion trajectory tracking control of musculoskeletal systems.