Functional Electrical Stimulation Therapy for Retraining Reaching and Grasping After Spinal Cord Injury and Stroke

The Role of Upper Extremity Motor Function in the Choice of Bladder Management in Those Unable to Volitionally Void due to Neurologic Dysfunction

It is estimated that 425,000 individuals with neurologic bladder dysfunction (spinal cordinjury, spina bifida and multiple sclerosis) are unable to volitionally void and must rely oncatheter drainage. Upper extremity (UE) motor function is one of the most important factors indetermining the type of bladder management chosen in individuals who cannot volitionally void. Novel bladder management solutions for those with impaired UE motor function and concurrent impairments involitional voiding continue to be an area of need. Those with poor UE motor function more often choose an indwelling catheter, whereas those with normal UE motor function more often choose clean intermittent catheterization.

Gait Training With Motor Relearning Program in Conjunction With Functional Electrical Stimulation in Quadriparesis Secondary to Cervical and Lumbar Myelopathy

Degenerative cervical myelopathy is a frequently encountered age-related pathology following compression of the spinal cord. This case report delineates the clinical manifestation of cervical and lumbar myelopathy in a 78-year-old male patient, characterised by chief complaints of difficulty in moving bilateral upper and lower extremities and difficulty in bed mobility. Motor impairment can manifest in three different presentations, which are paraparesis, hemiparesis, or quadriparesis. The motor relearning program incorporating functional electrical stimulation constitutes a rehabilitative approach used for the restoration of motor function. This study outlines the protocol for the physiotherapy intervention protocol, mainly focusing on gait training. Along with it, balance training, proprioceptive neuromuscular facilitation, etc., were also included. The goal of physiotherapy rehabilitation was to improve the patient's ability to do tasks related to daily living. The outcome measures used were the dynamic gait index, functional independence measure, and Modified Japanese Orthopaedic Association score. We document significant increases in muscular tone and power, improved active range of motion, enhancements in gait parameters, and notable advancements in the individual's functional independence through the implementation of a physiotherapeutic regimen.

A dry polymer nanocomposite transcutaneous electrode for functional electrical stimulation

BACKGROUND

Functional electrical stimulation (FES) can be used in rehabilitation to aid or improve function in people with paralysis. In clinical settings, it is common practice to use transcutaneous electrodes to apply the electrical stimulation, since they are non-invasive, and can be easily applied and repositioned as necessary. However, the current electrode options available for transcutaneous FES are limited and can have practical disadvantages, such as the need for a wet interface with the skin for better comfort and performance. Hence, we were motivated to develop a dry stimulation electrode which could perform equivalently or better than existing commercially available options.

METHODS

We manufactured a thin-film dry polymer nanocomposite electrode, characterized it, and tested its performance for stimulation purposes with thirteen healthy individuals. We compared its functionality in terms of stimulation-induced muscle torque and comfort level against two other types of transcutaneous electrodes: self-adhesive hydrogel and carbon rubber. Each electrode type was also tested using three different stimulators and different intensity levels of stimulation.

RESULTS

We found the proposed dry polymer nanocomposite electrode to be functional for stimulation, as there was no statistically significant difference between its performance to the other standard electrodes. Namely, the proposed dry electrode had comparable muscle torque generated and comfort level as the self-adhesive hydrogel and carbon rubber electrodes. From all combinations of electrode type and stimulators tested, the dry polymer nanocomposite electrode with the MyndSearch stimulator had the most comfortable average rating.

CONCLUSIONS

The dry polymer nanocomposite electrode is a durable and flexible alternative to existing self-adhesive hydrogel and carbon rubber electrodes, which can be used without the addition of a wet interfacing agent (i.e., water or gel) to perform as well as the current electrodes used for stimulation purposes.

Cycling using functional electrical stimulation therapy to improve motor function and activity in post-stroke individuals in early subacute phase: a systematic review with meta-analysis

BACKGROUND

Stroke necessitates interventions to rehabilitate individuals with disabilities, and the application of functional electrical stimulation therapy (FEST) has demonstrated potential in this regard. This study aimed to analyze the efficacy and effectiveness of cycling using FEST to improve motor function and lower limb activity in post-stroke individuals.

METHODS

We performed a systematic review according to the recommendations of the PRISMA checklist, searching MEDLINE, Cochrane, EMBASE, LILACS, and PEDro databases by July 2022, without any date or language limitations. Studies were selected using the following terms: stroke, electrical stimulation therapy, cycling, and clinical trials. Randomized or quasi-randomized clinical trials that investigated the effectiveness of cycling using FEST combined with exercise programs and cycling using FEST alone for motor function and activity in subacute post-stroke individuals were included. The quality of included trials was assessed using the PEDro scores. Outcome data were extracted from eligible studies and combined in random-effects meta-analyses. The quality of evidence was determined according to the Grading of Recommendations Assessment, Development, and Evaluation system.

RESULTS

Five randomized clinical trials involving 187 participants were included. Moderate-quality evidence indicates that cycling using FEST combined with exercise programs promotes relevant benefits in trunk control (MD 9 points, 95% CI 0.36-17.64) and walking distance (MD 94.84 m, 95% CI 39.63-150.05, I = 0%), the other outcomes had similar benefits. Cycling using FEST alone compared to exercise programs promotes similar benefits in strength, balance, walking speed, walking distance, and activities of daily living.

CONCLUSION

This systematic review provides low- to moderate-quality evidence that cycling using FEST may be an effective strategy to consider in improving motor function and activity outcomes for post-stroke individuals in the early subacute phase.

REVIEW REGISTRATION

PROSPERO (CRD42022345282).

Effectiveness of functional electrical stimulation machine in managing neurological diseases - A retrospective study

Background & Objective

Cerebrovascular Accident (CVA) or stroke, Spinal Cord injury can lead to neurological diseases resulting in major loss in motor function causing hemiplegia or tetraplegia. In 2019, according to The Global Burden of Diseases (GBD) CVA/Stroke is the second leading cause of death and the third leading cause of death and disability combined, globally. Its prevalence vary drastically among South Asian countries. The objective of this study was to determine the effectiveness of Functional Electrical Stimulation (FES) machine on neurologically impaired patients at the Physical Therapy department at IHHN, Karachi, Pakistan.

Method

In this retrospective study data was extracted from August 2016 to February 2022 on patients with neurological symptoms i.e. hemiplegia or paraplegia with muscle power of two or less on Manual Muscle Testing (MMT). The parameters for evaluating patients progress pre and post treatment were MMT results and their mobility status. The number of sessions ranged between 40 to 100 sessions of Functional Electrical Stimulation (FES) provided on alternate days according to the patient's need.

Result

Data of 51 patients who had completed their treatment were extracted and analyzed. The mean age of patients who completed treatment was 49.62 ± 17.26 years. Out of 51(100%), 30 (58.8%) were male and 21 (41.2%) were female. Pre- and post-treatment median (IQR) showed remarkable improvement in MMT of upper limb muscle (from 1.0 to 4.0) and lower limb muscle (from 2.0 to 4.0).

Conclusion

FES cycling is an effective treatment for patients with neurological impairments, as it resulted in improvement in both upper and lower limb muscle strength, along with mobility status.

Bioadhesive Technology Platforms

Bioadhesives have emerged as transformative and versatile tools in healthcare, offering the ability to attach tissues with ease and minimal damage. These materials present numerous opportunities for tissue repair and biomedical device integration, creating a broad landscape of applications that have captivated clinical and scientific interest alike. However, fully unlocking their potential requires multifaceted design strategies involving optimal adhesion, suitable biological interactions, and efficient signal communication. In this Review, we delve into these pivotal aspects of bioadhesive design, highlight the latest advances in their biomedical applications, and identify potential opportunities that lie ahead for bioadhesives as multifunctional technology platforms.

Advances in Conductive Hydrogel for Spinal Cord Injury Repair and Regeneration

Spinal cord injury (SCI) treatment represents a major challenge in clinical practice. In recent years, the rapid development of neural tissue engineering technology has provided a new therapeutic approach for spinal cord injury repair. Implanting functionalized electroconductive hydrogels (ECH) in the injury area has been shown to promote axonal regeneration and facilitate the generation of neuronal circuits by reshaping the microenvironment of SCI. ECH not only facilitate intercellular electrical signaling but, when combined with electrical stimulation, enable the transmission of electrical signals to electroactive tissue and activate bioelectric signaling pathways, thereby promoting neural tissue repair. Therefore, the implantation of ECH into damaged tissues can effectively restore physiological functions related to electrical conduction. This article focuses on the dynamic pathophysiological changes in the SCI microenvironment and discusses the mechanisms of electrical stimulation/signal in the process of SCI repair. By examining electrical activity during nerve repair, we provide insights into the mechanisms behind electrical stimulation and signaling during SCI repair. We classify conductive biomaterials, and offer an overview of the current applications and research progress of conductive hydrogels in spinal cord repair and regeneration, aiming to provide a reference for future explorations and developments in spinal cord regeneration strategies.

Fully implanted battery-free high power platform for chronic spinal and muscular functional electrical stimulation

Electrical stimulation of the neuromuscular system holds promise for both scientific and therapeutic biomedical applications. Supplying and maintaining the power necessary to drive stimulation chronically is a fundamental challenge in these applications, especially when high voltages or currents are required. Wireless systems, in which energy is supplied through near field power transfer, could eliminate complications caused by battery packs or external connections, but currently do not provide the harvested power and voltages required for applications such as muscle stimulation. Here, we introduce a passive resonator optimized power transfer design that overcomes these limitations, enabling voltage compliances of ± 20 V and power over 300 mW at device volumes of 0.2 cm2, thereby improving power transfer 500% over previous systems. We show that this improved performance enables multichannel, biphasic, current-controlled operation at clinically relevant voltage and current ranges with digital control and telemetry in freely behaving animals. Preliminary chronic results indicate that implanted devices remain operational over 6 weeks in both intact and spinal cord injured rats and are capable of producing fine control of spinal and muscle stimulation.

Development of an Aerogel-Based Wet Electrode for Functional Electrical Stimulation

Functional electrical stimulation (FES) has been a useful therapeutic tool in rehabilitation, particularly for people with paralysis. To deliver stimulation in its most basic setup, a stimulator and at least a pair of electrodes are needed. The electrodes are an essential part of the system since they allow the transduction of the stimulator signals into the body. Their performance can influence the experience of both patient and therapist in terms of movement generation, comfort, and ease of use. For non-invasive surface stimulation, current electrode options have several limitations involving their interfacing with the skin, practical inconveniences, and short-term functionality. Standard hydrogel electrodes tend to lose their adhesion with the skin quickly, while dry or textile electrodes require constant wetting to be comfortable. In this paper, we present the fabrication, characterization, and FES testing of a new aerogel-based wet electrode for surface stimulation applications for long-term and reusable FES applications. We investigated its functionality by stimulating the biceps brachii of twelve healthy individuals and collected elbow joint torque and comfort ratings for three different intensity levels (low, moderate, and high) of FES. Comparing to standard hydrogel electrodes, no statistically significant difference was found for any intensity of stimulation in either torque or comfort. Overall, the new aerogel-based electrode has an appropriate impedance, is flexible and soft, is conformable to the skin, has a high water absorption and retention, and can be used for FES purposes.

[Rehabilitation after Spinal Cord Injury : Current trends and principles]

Traumatic and non traumatic spinal cord injury are rare and an orphan disease in comparison to common diseases. Those affected represent a very special patient population in the treatment even at the site of the accident and in emergency medicine and require a high level of professional expertise. The rehabilitation with the complexity of a spinal cord injury can only succeed with a multiprofessional team that is less focused on the often similar diagnoses according to the International Classification of Diseases (ICD) but on functional disorders and associated activity impairments. Only then the best possible integration and participation/inclusion in sociocultural and professional life can be achieved. In addition to the importance of classical physiotherapy and occupational therapy, this article highlights important but often missing team players, such as neurourology and electrical stimulation. In addition, the problems of frequent and some less recognized complications, such as autonomic dysfunction and the benefits of airway management are highlighted. For a comprehensive overview of rehabilitation in spinal cord injury, reference textbooks and guidelines are recommended that are cited in the text.

Multi-Channel FES Gait Rehabilitation Assistance System Based on Adaptive sEMG Modulation

Functional electrical stimulation (FES) can be used to stimulate the lower-limb muscles to provide walking assistance to stroke patients. However, the existing surface electromyography (sEMG)-based FES control methods mostly only consider a single muscle with a fixed stimulation intensity and frequency. This study proposes a multi-channel FES gait rehabilitation assistance system based on adaptive myoelectric modulation. The proposed system collects sEMG of the vastus lateralis muscle on the non-affected side to predict the sEMG values of four targeted lower-limb muscles on the affected side using a bidirectional long short-term memory (BILSTM) model. Next, the proposed system modulates the real-time FES output frequency for four targeted muscles based on the predicted sEMG values to provide muscle force compensation. Fifteen healthy subjects were recruited to participate in an offline model-building experiment conducted to evaluate the feasibility of the proposed BILSTM model in predicting the sEMG values. The experimental results showed that the [Formula: see text] value of the best-obtained prediction result reached 0.85 using the BILSTM model, which was significantly higher than that using traditional prediction methods. Moreover, two patients after stroke were recruited in the online assisted-walking experiment to verify the effectiveness of the proposed walking-assistance system. The experimental results showed that the activation of the target muscles of the patients was higher after FES, and the gait movement data were significantly different before and after FES. The proposed system can be effectively applied to walking assistance for stroke patients, and the experimental results can provide new ideas and methods for sEMG-controlled FES rehabilitation applications.

Synergy-based functional electrical stimulation and robotic-assisted for retraining reach-to-grasp in stroke: a study protocol for a randomized controlled trial

BACKGROUND

Stroke survivors have long-term upper limb impairment, which impacts the quality of life (QOL) and social reintegration, but there is lack of effective therapeutic strategies and novel technologies. Customized multi-muscle functional electrical stimulation (FES) based on the muscle synergy of healthy adults and robotic-assisted therapy (RAT) have been proved efficacy respectively. Synergy-based FES combined with RAT can be a novel and more effective therapy for upper limb recovery of stroke survivors from the perspective of synergistic enhancement. However, few studies have examined the effectiveness of combined synergy-based FES and RAT, especially for motor control evaluated by reach-to-grasp (RTG) movements. The main objective of the following research protocol is to evaluate the effectiveness and efficacy, as well as adoptability, of FES-RAT and FES or RAT rehabilitation program for upper limb function improvement after stroke.

METHODS

This will be an assessor-blinded randomized controlled trial involving a 12-week intervention and a 6-month follow-up. Stratified randomization will be used to equally and randomly assign 162 stroke patients into the FES + conventional rehabilitation program (CRP) group, RAT + CRP group and FES-RAT + CRP group. Interventions will be provided in 5 sessions per week, with a total of 60 sessions. The primary outcome measurements will include the Fugl-Meyer Assessment and Biomechanical Assessment of RTG movements. The secondary outcome measurements will include quality of life and brain neuroplasticity assessments by MRI. Evaluations will be performed at five time points, including at baseline, 6 weeks and 12 weeks from the start of treatment, and 3 months and 6 months following the end of treatment. A two-way analysis of variance with repeated measures will be applied to examine the main effects of the group, the time factor and group-time interaction effects.

DISCUSSION

The results of the study protocol will provide high quality evidence for integrated synergy-based FES and RAT, and synergy-based FES alone and guide the design of more effective treatment methods for stroke rehabilitation.

TRIAL REGISTRATION

ChiCTR2300071588.

Robot-Inspired Human Impedance Control Through Functional Electrical Stimulation

Functional Electrical Stimulation is an effective tool to foster rehabilitation of neurological patients suffering from impaired motor functions. It can also serve as an assistive device to compensate for compromised motor functions in the chronic phase occurring after a disease or trauma. In all cases, the dominant paradigm in FES applications is that of aiding specialized, task-specific movements, such as reaching or grasping. Usually this is achieved by targeting specific muscle groups which are associated to the targeted motion by experts. A general purpose, FES-based control theory capable of enabling neurological patients to achieve a wide range of positional goals in their peri-personal space is still missing. In this paper, we present an early analysis of the performance achievable through a muscular impedance control loop employing FES to actuate force and movement. The control is evaluated in a test where the user's upper limb is moved by means of an exonerve to a series of target positions on a plane without providing visual feedback nor requiring volitional effort. The results allow to characterize the performance of such a setup over time and to assess how well can it generalize over different target positions in the user's peri-personal space. The current study population also allows to evaluate the effects of user's experience with FES systems on the overall performance during the test. The results indicate that the proposed control loop can generalize well over different arm poses.

Effects of Rehabilitation Therapy at Different Intervention Times on Daily Living Activity and Motor Function in Patients with Traumatic Spinal Cord Injury

Objectives: We investigated the impact of traumatic spinal cord injury (TSCI) on daily living activities and motor function of TSCI patients. Methods: A total of 88 TSCI patients were randomly divided into Group A (N=44) and Group B (N=44). Group A received rehabilitation treatment 7 days after the stabilization of vital signs, and Group B received rehabilitation treatment 30 days after hospitalization. Results: The compliance rate of Group A (93.18%) was higher than that of Group B (72.73%) (χ 2 =6.510, p<.05); The scores of American Spinal Injury Association (ASIA) and Activities of Daily Living (ADL) in Group A were higher than those in Group B. The self-rating score of anxiety and depression was lower than that of Group B (p<.05). Conclusion: For the rehabilitation treatment of TSCI patients, it is better to choose the intervention after the vital signs are stable to improve patients' ability for daily living activities and motor function.

Manipulating facial musculature with functional electrical stimulation as an intervention for major depressive disorder: a focused search of literature for a proposal

BACKGROUND

Major Depressive Disorder (MDD) is associated with interoceptive deficits expressed throughout the body, particularly the facial musculature. According to the facial feedback hypothesis, afferent feedback from the facial muscles suffices to alter the emotional experience. Thus, manipulating the facial muscles could provide a new "mind-body" intervention for MDD. This article provides a conceptual overview of functional electrical stimulation (FES), a novel neuromodulation-based treatment modality that can be potentially used in the treatment of disorders of disrupted brain connectivity, such as MDD.

METHODS

A focused literature search was performed for clinical studies of FES as a modulatory treatment for mood symptoms. The literature is reviewed in a narrative format, integrating theories of emotion, facial expression, and MDD.

RESULTS

A rich body of literature on FES supports the notion that peripheral muscle manipulation in patients with stroke or spinal cord injury may enhance central neuroplasticity, restoring lost sensorimotor function. These neuroplastic effects suggest that FES may be a promising innovative intervention for psychiatric disorders of disrupted brain connectivity, such as MDD. Recent pilot data on repetitive FES applied to the facial muscles in healthy participants and patients with MDD show early promise, suggesting that FES may attenuate the negative interoceptive bias associated with MDD by enhancing positive facial feedback. Neurobiologically, the amygdala and nodes of the emotion-to-motor transformation loop may serve as potential neural targets for facial FES in MDD, as they integrate proprioceptive and interoceptive inputs from muscles of facial expression and fine-tune their motor output in line with socio-emotional context.

CONCLUSIONS

Manipulating facial muscles may represent a mechanistically novel treatment strategy for MDD and other disorders of disrupted brain connectivity that is worthy of investigation in phase II/III trials.

Functional electrical stimulation therapy for upper extremity rehabilitation following spinal cord injury: a pilot study

STUDY DESIGN

Pilot study.

OBJECTIVES

To examine if functional electrical stimulation therapy (FEST) improves neuromuscular factors underlying upper limb function in individuals with SCI.

SETTING

A tertiary spinal cord rehabilitation center specialized in spinal cord injury care in Canada.

METHODS

We examined 29 muscles from 4 individuals living with chronic, cervical, and incomplete SCI. The analysis was focused on the changes in muscle activation, as well as on how the treatment could change the ability to control a given muscle or on how multiple muscles would be coordinated during volitional efforts.

RESULTS

There was evidence of gains in muscle strength, activation, and median frequency after the FEST. Gains in muscle activation indicated the activation of a greater number of motor units and gains in muscle median frequency the involvement of higher threshold, faster motor units. In some individuals, these changes were smaller but accompanied by increased control over muscle contraction, evident in a greater ability to sustain a volitional contraction, reduce the co-contraction of antagonist muscles, and provide cortical drive.

CONCLUSIONS

FEST increases muscle strength and activation. Enhanced control of muscle contraction, reduced co-contraction of antagonist muscles, and a greater presence of cortical drive were some of the findings supporting the effects of FEST at the sensory-motor integration level.

Stroke Rehabilitation and Motor Recovery

OBJECTIVE

Up to 50% of the nearly 800,000 patients who experience a new or recurrent stroke each year in the United States fail to achieve full independence afterward. More effective approaches to enhance motor recovery following stroke are needed. This article reviews the rehabilitative principles and strategies that can be used to maximize post-stroke recovery.

LATEST DEVELOPMENTS

Evidence dictates that mobilization should not begin prior to 24 hours following stroke, but detailed guidelines beyond this are lacking. Specific classes of potentially detrimental medications should be avoided in the early days poststroke. Patients with stroke who are unable to return home should be referred for evaluation to an inpatient rehabilitation facility. Research suggests that a substantial increase in both the dose and intensity of upper and lower extremity exercise is beneficial. A clinical trial supports vagus nerve stimulation as an adjunct to occupational therapy for motor recovery in the upper extremity. The data remain somewhat mixed as to whether robotics, transcranial magnetic stimulation, functional electrical stimulation, and transcranial direct current stimulation are better than dose-matched traditional exercise. No current drug therapy has been proven to augment exercise poststroke to enhance motor recovery.

ESSENTIAL POINTS

Neurologists will collaborate with rehabilitation professionals for several months following a patient's stroke. Many questions still remain about the ideal exercise regimen to maximize motor recovery in patients poststroke. The next several years will likely bring a host of new research studies exploring the latest strategies to enhance motor recovery using poststroke exercise.

Effectiveness of backward walking with functional electrical stimulation on the rectus femoris and tibialis anterior for patients with chronic stroke

BACKGROUND

Backward walking is considered as a newly rising method used to enhance gait abilities, but evidence remains unclear.

OBJECTIVE

To identify whether backward walking with functional electrical stimulation (FES) triggered by a foot switch on the rectus femoris and tibialis anterior could be effective in improving gait parameters of stroke survivors.

METHODS

This was a cross-sectional study that included fourteen subjects with chronic stroke. Three walking conditions were performed at random: backward walking with FES attached onto the rectus femoris and tibialis anterior (RF+TA), backward walking with FES attached onto the tibialis anterior (TA only), and without electrical intervention (non-FES). The Zebris was used to assess the spatiotemporal gait parameters. Each condition was measured three times and the average value was used for analysis.

RESULTS

Results showed significant increases in gait speed, cadence, step length, mid-stance percentage, maximal force in the affected midfoot (p < 0.05), and significant decreases in the double stance phase in the RF+TA condition compared to the TA only and the non-FES conditions (p < 0.05).

CONCLUSION

Functional electrical stimulation to the rectus femoris and tibialis anterior during backward walking could be a clinically effective method to improve gait ability of stroke survivors.

STIMGRASP: A Home-Based Functional Electrical Stimulator for Grasp Restoration in Daily Activities

Thousands of people currently suffer from motor limitations caused by SCI and strokes, which impose personal and social challenges. These individuals may have a satisfactory recovery by applying functional electrical stimulation that enables the artificial restoration of grasping after a muscular conditioning period. This paper presents the STIMGRASP, a home-based functional electrical stimulator to be used as an assistive technology for users with tetraplegia or hemiplegia. The STIMGRASP is a microcontrolled stimulator with eight multiplexed and independent symmetric biphasic constant current output channels with USB and Bluetooth communication. The system generates pulses with frequency, width, and maximum amplitude set at 20 Hz, 300 µs/phase, and 40 mA (load of 1 kΩ), respectively. It is powered by a rechargeable lithium-ion battery of 3100 mAh, allowing more than 10 h of continuous use. The development of this system focused on portability, usability, and wearability, resulting in portable hardware with user-friendly mobile app control and an orthosis with electrodes, allowing the user to carry out muscle activation sequences for four grasp modes to use for achieving daily activities.

Functional Electrical Stimulation (FES) in the Diagnosis and Treatment of Musculoskeletal and Neuromuscular Control Abnormalities in Horses - Selected Case Studies

When diagnosing neuromuscular injury and pain, the use of biomechanical evaluations to assess the mechanics of movement patterns has been useful in the human population. Functional electrical stimulation (FES) is a technology that can create action potentials to produce musculoskeletal movement that is almost indistinguishable from the voluntary kinematics produced by the nervous system. To create controlled and precise musculoskeletal movements in humans and in horses, FES has been shown to be effective. In humans, the kinematic information obtained from FES data has been utilized to direct further diagnostics, and/or to assist in the development of specific treatment protocols. In addition, since FES creates dynamic movement while in a static position, the ability to isolate the regions of dysfunction improves without the confounding factors of over-the-ground movement and other artifacts caused by environmental stimuli. This paper explores the transfer of the use of FES in human diagnostics to clinical use in horses. Three equine case studies discuss how FES was employed as a tool in the diagnosis and treatment of equine musculoskeletal and neuromuscular control disorders.

Adaptive Hybrid FES-Force Controller for Arm Exosuit

Patients suffering from neuromuscular diseases experience motor disabilities which hinder their independence during activities of daily living (ADLs). For such impaired subjects, robotic devices and Functional Electrical Stimulation (FES) are technologies commonly used to rehabilitate lost functions. Nevertheless, both systems present some limitations, and merging FES and robots in Hybrid Robotic Rehabilitation Systems allows to overcome these boundaries. Here we propose for the first time a hybrid cooperative controller involving FES and a soft wearable upper arm exosuit to rehabilitate elbow movements. We tested the designed hybrid controller on six healthy participants. The results showed how the proposed hybrid controller allowed the wearers to perform flexion movements with no significant decrease in accuracy and precision with respect to the exosuit alone, while significantly decreasing the fatigue level by about 63% and delaying its onset with respect to the FES action alone.

A Comprehensive Framework for the Modelling of Cartesian Force Output in Human Limbs

Neuromuscular functional electrical stimulation represents a valid technique for functional rehabilitation or, in the form of a neuroprosthesis, for the assistance of neurological patients. However, the selected stimulation of single muscles through surface electrodes remains challenging particularly for the upper extremity. In this paper, we present the MyoCeption, a comprehensive setup, which enables intuitive modeling of the user's musculoskeletal system, as well as proportional stimulation of the muscles with 16-bit resolution through up to 10 channels. The system can be used to provide open-loop force control, which, if coupled with an adequate body tracking system, can be used to implement an impedance control where the control loop is closed around the body posture. The system is completely self-contained and can be used in a wide array of scenarios, from rehabilitation to VR to teleoperation. Here, the MyoCeption's control environment has been experimentally validated through comparison with a third-party simulation suite. The results indicate that the musculoskeletal model used for the MyoCeption provides muscle geometries that are qualitatively similar to those computed in the baseline model.

A Prediction Model for Various Treatment Pathways of Upper Extremity in Tetraplegia

Upper extremity function is essential for the autonomy in patients with cervical spinal cord injuries and consequently a focus of the rehabilitation and treatment efforts. Routinely, an individualized treatment plan is proposed to the patient by an interprofessional team. It dichotomizes into a conservative and a surgical treatment pathway. To select an optimal pathway, it is important to define predictors that substantiate the treatment strategy. Apart from standard assessments (Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), the manual muscle test (MRC), and lower motoneuron integrity of key actuators for hand function performed by motor point (MP) mapping might serve as a possible predictor. Type of damage (upper motor neuron (UMN) or lower motor neuron (LMN) lesion) influences hand posture and thus treatment strategy as positioning and splinting of fingers, hands, arms, and surgical reconstructive procedures (muscle-tendon or nerve transfers) in choice and timing of intervention. For this purpose, an analysis of a database comprising 220 patients with cervical spinal cord injury is used. It includes ISNCSCI, MRC, and MP mapping of defined muscles at selected time points after injury. The ordinal regression analysis performed indicates that MP and ASIA impairment scale (AIS) act as predictors of muscle strength acquisition. In accordance with the innervation status defined by MP, electrical stimulation (ES) is executed either via nerve or direct muscle stimulation as a supplementary therapy to the traditional occupational and physiotherapeutic treatment methods. Depending on the objective, ES is applied for motor learning, strengthening, or maintenance of muscle contractile properties. By employing ES, hand and arm function can be predicted by MP and AIS and used as the basis for providing an individualized treatment plan.

Soft robotics and functional electrical stimulation advances for restoring hand function in people with SCI: a narrative review, clinical guidelines and future directions

Background

Recovery of hand function is crucial for the independence of people with spinal cord injury (SCI). Wearable devices based on soft robotics (SR) or functional electrical stimulation (FES) have been employed to assist the recovery of hand function both during activities of daily living (ADLs) and during therapy. However, the implementation of these wearable devices has not been compiled in a review focusing on the functional outcomes they can activate/elicit/stimulate/potentiate. This narrative review aims at providing a guide both for engineers to help in the development of new technologies and for clinicians to serve as clinical guidelines based on the available technology in order to assist and/or recover hand function in people with SCI.

Methods

A literature search was performed in Scopus, Pubmed and IEEE Xplore for articles involving SR devices or FES systems designed for hand therapy or assistance, published since 2010. Only studies that reported functional outcomes from individuals with SCI were selected. The final collections of both groups (SR and FES) were analysed based on the technical aspects and reported functional outcomes.

Results

A total of 37 out of 1101 articles were selected, 12 regarding SR and 25 involving FES devices. Most studies were limited to research prototypes, designed either for assistance or therapy. From an engineering perspective, technological improvements for home-based use such as portability, donning/doffing and the time spent with calibration were identified. From the clinician point of view, the most suitable technical features (e.g., user intent detection) and assessment tools should be determined according to the particular patient condition. A wide range of functional assessment tests were adopted, moreover, most studies used non-standardized tests.

Conclusion

SR and FES wearable devices are promising technologies to support hand function recovery in subjects with SCI. Technical improvements in aspects such as the user intent detection, portability or calibration as well as consistent assessment of functional outcomes were the main identified limitations. These limitations seem to be be preventing the translation into clinical practice of these technological devices created in the laboratory.

Analysis of the movements generated by a multi-field functional electrical stimulation device for upper extremity rehabilitation

BACKGROUND

the most common chronic sequela after stroke is the loss of arm function, and functional electrical stimulation (FES) applied to the forearm muscles is one of the options to treat it. Surface multi-field electrodes have emerged, showing a great potential to improve the selectivity of the stimulation, to delay muscle fatigue, and to provide easier donning and doffing. The muscular selectivity takes on special relevance in the rehabilitation of upper extremity as hand dexterity requires a wide diversity of specific muscle actions.

METHODS

this pilot study analyses the movements generated in the wrist and fingers using a commercial multi-field technology-based FES device (Fesia Grasp). The study included 5 patients with hemiplegic subacute stroke, in which a scanning of all cathodes of the electrode was carried out daily for 5 days, in 2 different forearm positions, with the resulting movements being labelled by experienced therapists.

RESULTS

The aim of this pilot study was to determine if there were differences between subjects and between forearm positions in terms of produced movements. Movements of the wrist (2 movements) and the fingers (6 movements) could be achieved in 2 different forearm positions.

CONCLUSIONS

the multi-field electrode of Fesia Grasp enables to generate a wide range of movements of the hand in different positions. This fact could allow to produce more physiological movement patterns during the rehabilitation process with FES, which could have a beneficial effect on the recovery of patients with neurological diseases.

Surface EMG in Subacute and Chronic Care after Traumatic Spinal Cord Injuries

Background: Traumatic spinal cord injury (SCI) is a devastating condition commonly originating from motor vehicle accidents or falls. Trauma care after SCI is challenging; after decompression surgery and spine stabilization, the first step is to assess the location and severity of the traumatic lesion. For this, clinical outcome measures are used to quantify the residual sensation and volitional control of muscles below the level of injury. These clinical assessments are important for decision-making, including the prediction of the recovery potential of individuals after the SCI. In clinical care, this quantification is usually performed using sensation and motor scores, a semi-quantitative measurement, alongside the binary classification of the sacral sparing (yes/no). Objective: In this perspective article, I review the use of surface EMG (sEMG) as a quantitative outcome measurement in subacute and chronic trauma care after SCI. Methods: Here, I revisit the main findings of two comprehensive scoping reviews recently published by our team on this topic. I offer a perspective on the combined findings of these scoping reviews, which integrate the changes in sEMG with SCI and the use of sEMG in neurorehabilitation after SCI. Results: sEMG provides a complimentary assessment to quantify the residual control of muscles with great sensitivity and detail compared to the traditional clinical assessments. Our scoping reviews unveiled the ability of the sEMG assessment to detect discomplete lesions (muscles with absent motor scores but present sEMG). Moreover, sEMG is able to measure the spontaneous activity of motor units at rest, and during passive maneuvers, the evoked responses with sensory or motor stimulation, and the integrity of the spinal cord and descending tracts with motor evoked potentials. This greatly complements the diagnostics of the SCI in the subacute phase of trauma care and deepens our understanding of neurorehabilitation strategies during the chronic phase of the traumatic injury. Conclusions: sEMG offers important insights into the neurophysiological factors underlying sensorimotor impairment and recovery after SCIs. Although several qualitative or semi-quantitative outcome measures determine the level of injury and the natural recovery after SCIs, using quantitative measures such as sEMG is promising. Nonetheless, there are still several barriers limiting the use of sEMG in the clinical environment and a need to advance high-density sEMG technology.

Upper Extremity Contralaterally Controlled Functional Electrical Stimulation Versus Neuromuscular Electrical Stimulation in Post-Stroke Individuals: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Electrical stimulation has been employed as a safe and effective therapy for improving arm function after stroke. Contralaterally controlled functional electrical stimulation (CCFES) is a unique method that has progressed from application in small feasibility studies to implementation in several randomized controlled trials. However, no meta-analysis has been conducted to summarize its efficacy.

OBJECTIVE

To summarize the effect size of CCFES through measures of upper extremity motor recovery compared with that of neuromuscular electrical stimulation (NMES).

METHODS

The PubMed, Cochrane Library, EMBASE, Scopus, and Google Scholar databases were searched. Randomized controlled trials (RCTs) were selected and subjected to meta-analysis and risk of bias assessment.

RESULTS

6 RCTs were selected and 267 participants were included. The Upper Extremity Fugl-Meyer assessment (UEFMA) was included in all studies, the Box and Blocks test (BBT) and active range of motion (AROM) were included in 3 and 4 studies, respectively. The modified Barthel Index (mBI) and Arm Motor Abilities Test (AMAT) were included in 2 and 3 studies, respectively. The CCFES group demonstrated greater improvement than the NMES did in UEFMA (SMD = .42, 95% CI = .07-.76), BBT (SMD = .48, 95% CI = .10-.86), AROM (SMD = .54, 95% CI = .23-.86), and mBI (SMD = .54, 95% CI = .12-.97). However, the results for AMAT did not differ significantly (SMD = .34, 95% CI = -.03-.72).

CONCLUSION

Contralaterally controlled functional electrical stimulation produced greater improvements in upper extremity hemiplegia in people with stroke than NMES did. PROSPERO registration number: CRD42021245831.

Efficacy of Four-Channel Functional Electrical Stimulation on Moderate Arm Paresis in Subacute Stroke Patients—Results from a Randomized Controlled Trial

This preliminary randomized clinical trial explores the efficacy of task-oriented electromyography (EMG)-triggered multichannel functional electrical stimulation (EMG-MES) compared to single-channel cyclic neuromuscular electrical stimulation (cNMES) on regaining control of voluntary movements (CVM) and the ability to execute arm-hand-activities in subacute stroke patients with moderate arm paresis. Twelve ischemic stroke patients (Fugl-Meyer Assessment Arm Section (FMA-AS) score: 19–47) with comparable demographics were block-randomized to receive 15 sessions of cNMES or EMG-MES over three weeks additionally to a conventional neurorehabilitation program including task-oriented arm training. FMA-AS, Box-and-Block Test (BBT), and Stroke-Impact-Scale (SIS) were recorded at baseline and follow-up. All participants demonstrated significant improvement in FMA-AS and BBT. Participants treated with EMG-MES had a higher mean gain in FMA-AS than those treated with cNMES. In the SIS daily activities domain, both groups improved non-significantly; participants in the EMG-MES group had higher improvement in arm-hand use and stroke recovery. EMG-MES treatment demonstrated a higher gain of CVM and self-reported daily activities, arm-hand use, and stroke recovery compared to cNMES treatment of the wrist only. The protocol of this proof-of-concept study seems robust enough to be used in a larger trial to confirm these preliminary findings.

Execution of natural manipulation in the air enhances the beta-rhythm intermuscular coherences of the human arm depending on muscle pairs

Natural manipulation tasks in air consist of two kinematic components: a grasping component, with activation of the hand muscles, and a lifting component, with activation of the proximal muscles. However, it remains unclear whether the synchronized motor commands to the hand/proximal arm muscles are divergently controlled during the task. Therefore, we examined how intermuscular coherence was modulated depending on the muscle combinations during grip and lift (G&L) tasks. Electromyograms (EMGs) were recorded from the biceps brachii (BB), triceps brachii (TB), flexor digitorum superficialis (FDS), and extensor digitorum communis (EDC) muscles. The participants were required to maintain G&L tasks involving a small cubical box with the thumb and index and middle fingers. Consequently, we found that the beta-rhythm coherence (15-35 Hz) in BB-TB, BB-FDS, and TB-EDC pairs during G&L was significantly larger than that during the isolated task with cocontraction of the two target muscles but not BB-EDC, TB-FDS, and FDS-EDC (task and muscle pair specificities). These increases in beta-rhythm coherence were also observed in intramuscular EMG recordings. Furthermore, the results from the execution of several mimic G&L tasks revealed that the separated task-related motor signals and combinations between the motor signals/sensations of the fingertips or object load had minor contributions to the increase in the coherence. These results suggest that during G&L the central nervous system regulates synchronous drive onto motoneurons depending on the muscle pairs and that the multiple combination effect of the sensations of touch/object load and motor signals in the task promotes the synchrony of these pairs.NEW & NOTEWORTHY Natural manipulation in air consists of two kinematic components: grasping, with activation of hand muscles, and lifting, with activation of proximal muscles. We show that during the maintenance of object manipulation in air the central nervous system regulates the synchronous drive onto human motoneuron pools depending on the hand/proximal muscle pairs and that the multiple combination effect of the sensations of touch/object load and motor signals in the task promotes the synchrony of these pairs.

Trans-Spinal Electrical Stimulation Therapy for Functional Rehabilitation after Spinal Cord Injury: Review

Spinal cord injury (SCI) is one of the most debilitating injuries in the world. Complications after SCI, such as respiratory issues, bowel/bladder incontinency, pressure ulcers, autonomic dysreflexia, spasticity, pain, etc., lead to immense suffering, a remarkable reduction in life expectancy, and even premature death. Traditional rehabilitations for people with SCI are often insignificant or ineffective due to the severity and complexity of the injury. However, the recent development of noninvasive electrical neuromodulation treatments to the spinal cord have shed a ray of hope for these individuals to regain some of their lost functions, a reduction in secondary complications, and an improvement in their life quality. For this review, 250 articles were screened and about 150 were included to summarize the two most promising noninvasive spinal cord electrical stimulation methods of SCI rehabilitation treatment, namely, trans-spinal direct current stimulation (tsDCS) and trans-spinal pulsed current stimulation (tsPCS). Both treatments have demonstrated good success in not only improving the sensorimotor function, but also autonomic functions. Due to the noninvasive nature and lower costs of these treatments, in the coming years, we expect these treatments to be integrated into regular rehabilitation therapies worldwide.

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.

A Flexible Pulse Generator Based on a Field Programmable Gate Array Architecture for Functional Electrical Stimulation

Non-invasive Functional Electrical Stimulation (FES) is a technique applied for motor rehabilitation of patients with central nervous system injury. This technique requires programmable multichannel systems to configure the stimulation parameters (amplitude, frequency, and pulse width). Most FES systems are based on microcontrollers with fixed architecture; this limits the control of the parameters and the scaling to multiple channels. Although field programmable gate arrays (FPGA) have been used in FES systems as alternative to microcontrollers, most of them focus on signal acquisition, processing, or communication functions, or are for invasive stimulation. A few FES systems report using FPGAs for parameter configuration and pulse generation in non-invasive FES. However, generally they limit the value of the frequency or amplitude parameters to enable multichannel operation. This restricts free selection of parameters and implementation of modulation patterns, previously reported to delay FES-induced muscle fatigue. To overcome those limitations, this paper presents a proof-of-concept (technology readiness level three-TRL 3) regarding the technical feasibility and potential use of an FPGA-based pulse generator for non-invasive FES applications (PG-nFES). The main aims were: (1) the development of a flexible pulse generator for FES applications and (2) to perform a proof-of-concept of the system, comprising: electrical characterization of the stimulation parameters, and verification of its potential for upper limb FES applications. Biphasic stimulation pulses with high linearity (r² > 0.9998) and repeatability (>0.81) were achieved by combining the PG-nFES with a current-controlled output stage. Average percentage error in the characterizations was under 3% for amplitude (1–48 mA) and pulse width (20–400 μs), and 0% for frequency (10–150 Hz). A six-channel version of the PG-nFES was implemented to demonstrate the scalability feature. The independence of parameters was tested with three patterns of co-modulation of two parameters. Moreover, two complete FES channels were implemented and the claimed features of the PG-nFES were verified by performing upper limb functional movements involving the hand and the arm. Finally, the system enabled implementation of a stimulation pattern with co-modulation of frequency and pulse width, applied successfully for efficient elbow during repetitions of a functional movement.

Personalized protocol and scoring scale for functional electrical stimulation of the hand: A pilot feasibility study

BACKGROUND

Complex personalized Functional Electrical Stimulation (FES) protocols for calibrating parameters and electrode positioning have been proposed, most being time-consuming or technically cumbersome for clinical settings. Therefore, there is a need for new personalized FES protocols that generate comfortable, functional hand movements, while being feasible for clinical translation.

OBJECTIVE

To develop a personalized FES protocol, comprising electrode placement and parameter selection, to generate hand opening (HO), power grasp (PW) and precision grip (PG) movements, and compare in a pilot feasibility study its performance to a non-personalized protocol based on standard FES guidelines.

METHODS

Two FES protocols, one personalized (P1) and one non-personalized (P2), were used to produce hand movements in twenty-three healthy participants. FES-induced movements were assessed with a new scoring scale which comprises items for selectivity, functionality, and comfort.

RESULTS

Higher FES-HSS scores were obtained with P1 for all movements: HO (p= 0.00013), PW (p= 0.00007), PG (p= 0.00460). Electrode placement time was significantly shorter for P2 (p= 0.00003). Comfort scores were similar for both protocols.

CONCLUSIONS

The personalized protocol for electrode placement and parameter selection enabled functional FES-induced hand movements and presented advantages over a non-personalized protocol. This protocol warrants further investigation to confirm its suitability for developing upper-limb rehabilitation interventions with clinical translational potential.

Combining Action Observation Treatment with a Brain-Computer Interface System: Perspectives on Neurorehabilitation

Action observation treatment (AOT) exploits a neurophysiological mechanism, matching an observed action on the neural substrates where that action is motorically represented. This mechanism is also known as mirror mechanism. In a typical AOT session, one can distinguish an observation phase and an execution phase. During the observation phase, the patient observes a daily action and soon after, during the execution phase, he/she is asked to perform the observed action at the best of his/her ability. Indeed, the execution phase may sometimes be difficult for those patients where motor impairment is severe. Although, in the current practice, the physiotherapist does not intervene on the quality of the execution phase, here, we propose a stimulation system based on neurophysiological parameters. This perspective article focuses on the possibility to combine AOT with a brain–computer interface system (BCI) that stimulates upper limb muscles, thus facilitating the execution of actions during a rehabilitation session. Combining a rehabilitation tool that is well-grounded in neurophysiology with a stimulation system, such as the one proposed, may improve the efficacy of AOT in the treatment of severe neurological patients, including stroke patients, Parkinson’s disease patients, and children with cerebral palsy.

Feasibility and significance of stimulating interscapular muscles using transcutaneous functional electrical stimulation in able-bodied individuals

OBJECTIVE

The study objective was to assess the feasibility of stimulating the lower trapezius (LT), the upper trapezius (UT) and serratus anterior (SA) muscles along with anterior or middle deltoid, using surface functional electrical stimulation (FES). The secondary aim was to understand the effects of LT, UT, and SA stimulation on maximum arm reach achieved in shoulder flexion and abduction.

DESIGN

Single arm interventional study.

SETTING

Inpatient Rehabilitation Hospital.

PARTICIPANTS

Ten healthy volunteers.

INTERVENTION

Participants completed 10 trials for each of the 3 conditions in flexion and abduction, i.e. (1) Active voluntary flexion or abduction, (2) FES for anterior deltoid for flexion or middle deltoid for abduction, and (3) FES for LT, UT, and SA along with anterior deltoid for flexion or middle deltoid for abduction.

OUTCOME MEASURES

Maximum arm reach and percent angle relative to the voluntary movement were computed from motion capture data for each condition. Wilcoxon signed-rank test was used to compare the maximum reach between two FES conditions.

RESULTS

The study results showed that all three interscapular muscles can be stimulated using surface FES. Maximum reach in abduction was greater for FES of middle deltoid along with the interscapular muscles (51.77° ± 17.54°) compared to FES for middle deltoid alone (43.76° ± 15.32°; Z = -2.701, P = 0.007). Maximum reach in flexion for FES of anterior deltoid, along with interscapular muscles, was similar to that during FES of anterior deltoid alone.

CONCLUSION

Interscapular muscles can be stimulated using surface FES devices and should be engaged during rehabilitation as appropriate.

Implantable brain-computer interface for neuroprosthetic-enabled volitional hand grasp restoration in spinal cord injury

Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in one 21-year-old male subject with complete cervical quadriplegia (C5 American Spinal Injury Association Impairment Scale A) using a portable fully implanted brain-computer interface within the home environment. The brain-computer interface consists of subdural surface electrodes placed over the dominant-hand motor cortex and connects to a transmitter implanted subcutaneously below the clavicle, which allows continuous reading of the electrocorticographic activity. Movement-intent was used to trigger functional electrical stimulation of the dominant hand during an initial 29-weeks laboratory study and subsequently via a mechanical hand orthosis during in-home use. Movement-intent information could be decoded consistently throughout the 29-weeks in-laboratory study with a mean accuracy of 89.0% (range 78-93.3%). Improvements were observed in both the speed and accuracy of various upper extremity tasks, including lifting small objects and transferring objects to specific targets. At-home decoding accuracy during open-loop trials reached an accuracy of 91.3% (range 80-98.95%) and an accuracy of 88.3% (range 77.6-95.5%) during closed-loop trials. Importantly, the temporal stability of both the functional outcomes and decoder metrics were not explored in this study. A fully implanted brain-computer interface can be safely used to reliably decode movement-intent from motor cortex, allowing for accurate volitional control of hand grasp.

A wearable electromyography-controlled functional electrical stimulation system improves balance, gait function, and symmetry in older adults

BACKGROUND

Wearable technologies have been developed for healthy aging. The technology for electromyography (EMG)-controlled functional electrical stimulation (FES) systems has been developed, but research on how helpful it is in daily life has been insufficient.

OBJECTIVE

The purpose of this study was to investigate the effect of the EMG-controlled FES system on muscle morphology, balance, and gait in older adults.

METHODS

Twenty-nine older adults were evaluated under two randomly assigned conditions (non-FES and FES assists). Muscle morphology, balance, gait function, and muscle effort during gait were measured using ultrasonography, a physical test, a gait analysis system, and EMG.

RESULTS

The EMG-controlled FES system improved gait speed by 11.1% and cadence by 15.6% (P< 0.01). The symmetry ratio of the bilateral gastrocnemius was improved by 9.9% in the stance phase and 11.8% in the swing phase (P< 0.05). The degrees of coactivation of the knee and ankle muscles were reduced by 45.1% and 50.5%, respectively (P< 0.05). Balance improved by 6-10.7% (P< 0.01).

CONCLUSION

The EMG-controlled FES system is useful for balance and gait function by increasing muscle symmetry and decreasing muscle coactivation during walking in older adults.

Electrical Stimulation Promotes Stem Cell Neural Differentiation in Tissue Engineering

Nerve injuries and neurodegenerative disorders remain serious challenges, owing to the poor treatment outcomes of in situ neural stem cell regeneration. The most promising treatment for such injuries and disorders is stem cell-based therapies, but there remain obstacles in controlling the differentiation of stem cells into fully functional neuronal cells. Various biochemical and physical approaches have been explored to improve stem cell-based neural tissue engineering, among which electrical stimulation has been validated as a promising one both in vitro and in vivo. Here, we summarize the most basic waveforms of electrical stimulation and the conductive materials used for the fabrication of electroactive substrates or scaffolds in neural tissue engineering. Various intensities and patterns of electrical current result in different biological effects, such as enhancing the proliferation, migration, and differentiation of stem cells into neural cells. Moreover, conductive materials can be used in delivering electrical stimulation to manipulate the migration and differentiation of stem cells and the outgrowth of neurites on two- and three-dimensional scaffolds. Finally, we also discuss the possible mechanisms in enhancing stem cell neural differentiation using electrical stimulation. We believe that stem cell-based therapies using biocompatible conductive scaffolds under electrical stimulation and biochemical induction are promising for neural regeneration.

(-)-Epicatechin reduces muscle waste after complete spinal cord transection in a murine model: role of ubiquitin-proteasome system

The skeletal muscle mass reduces 30-60% after spinal cord injury, this is mostly due to protein degradation through ubiquitin-proteasome system. In this work, we propose that the flavanol (-)-epicatechin, due its widespread biological effects on muscle health, can prevent muscle mass decrease after spinal cord injury. Thirty-six female Long Evans rats were randomized into 5 groups: (1) Spinal cord injury 7 days, (2) Spinal cord injury + (-)-epicatechin 7 days, (3) Spinal cord injury 30 days, (4) Spinal cord injury + (-)-epicatechin 30 days and (5) Sham (Only laminectomy). Hind limb perimeter, muscle cross section area, fiber cross section area and ubiquitin-proteasome system protein expression together with total protein ubiquitination were assessed. At 30 days Spinal cord injury group lost 49.52 ± 2.023% of muscle cross section area (-)-epicatechin treated group lost only 24.28 ± 15.45% being a significant difference. Ubiquitin-proteasome markers showed significant changes. FOXO1a increased in spinal cord injury group vs Sham (-)-epicatechin reduced this increase. In spinal cord injury group MAFbx increased significantly vs Sham but decrease in (-)-epicatechin treatment group at 30 days. At 7 and 30 days MuRF1 increased in the spinal cord injury and decreased in the (-)-epicatechin group. The global protein ubiquitination increases after spinal cord injury, epicatechin treatment induce a significant decrease in protein ubiquitination. These results suggest that (-)-epicatechin reduces the muscle waste after spinal cord injury through down regulation of the ubiquitin-proteasome system.

Multicentre, single-blind randomised controlled trial comparing MyndMove neuromodulation therapy with conventional therapy in traumatic spinal cord injury: a protocol study

INTRODUCTION

This protocol is describing a multicentre, single-blind randomised controlled trial. The objective is to compare the efficacy of MyndMove therapy versus conventional therapy (CT) in improving upper extremity function in individuals with C4-C7 traumatic, incomplete spinal cord injury (SCI). It is being conducted in two US and two Canadian SCI rehabilitation centres.

METHODS AND ANALYSIS

Sixty people aged 18 years or older with a C4-C7 incomplete (AIS B-D) SCI between 4 months and 8 years postinjury are randomised to receive 40 sessions of MyndMove neuromodulation therapy or CT within a 14-week period of time. Therapy sessions are 1 hour in duration with a dose of 3-5 sessions per week. Assessments occur prior to randomisation, after 20 sessions, after 40 sessions and 10 weeks after the last session. The primary outcome measure is the efficacy of MyndMove therapy versus CT in improving upper extremity function as measured by Spinal Cord Independence Measure III: Self-Care subscore after 40 sessions. Secondary outcomes include: (1) improvements in the SCIM mobility subscore; (2) upper limb functions measured by Graded Redefined Assessment of Strength, Sensibility and Prehension and (3) Toronto Rehab Institute Hand Function Test; (4) To assess safety as measured by serious and non-serious adverse events recorded for participants in both groups of the study population over the duration of the study; (5) to compare the change in quality of life as measured by the Spinal Cord Injury-Quality of Life; and (6) to evaluate the impact on healthcare resource utilisation.

ETHICS AND DISSEMINATION

All ethical approvals were obtained prior to enrolling any participants. Dissemination of the results of the study will be made at peer-reviewed academic meetings and through peer-reviewed medical journals TRIAL REGISTRATION NUMBER: NCT03439319.