Functional Electrical Stimulation Research Articles

Physical and occupational therapists' learning needs and preferences for education on functional electrical stimulation: A qualitative descriptive study.

Functional electrical stimulation (FES) is an evidence-based intervention that is rarely used by Canadian physical therapists (PTs) and occupational therapists (OTs). A common barrier to FES implementation is a lack of knowledge and training. FES learning resources that meet therapists' learning needs and preferences may address this barrier. To explore OTs' and PTs' perspectives on the utility of FES e-learning resources, including whether the resources met their learning needs and preferences. Through this qualitative descriptive study, feedback on FES e-learning resources was solicited from 5 PTs and 18 OTs who work clinically, but do not use FES. Participants reviewed ≥3 prerecorded lectures on FES topics and then completed a semi-structured interview. Participants were asked about the lectures' content, delivery, ease of use and comprehensibility, and were asked to suggest modifications to facilitate self-directed learning about FES. Interviews were analyzed using conventional content analysis. Three themes were identified. (1) Feedback on FES e-learning: the content and delivery of the prerecorded lectures facilitated participants' learning, although opportunities to improve content and delivery were identified. (2) Factors influencing FES learning needs and preferences: Participants identified internal (i.e., baseline knowledge, learning style) and external (i.e., learning with colleagues, practice setting) factors that affected learning. Themes 1 and 2 impacted (3) the effects of FES e-learning: Participants described the outcomes of their FES e-learning, including increases in FES knowledge, confidence, and use in clinical practice. Therapists' perceived the FES e-learning resources to be useful and to address their learning needs and preferences.

Efficacy of Dashmool Vasti as an adjuvant therapy with the standard of care (modern + physiotherapy) in the rehabilitation of stroke as compared to standard of care - a clinical trial protocol.

Stroke is ischemia and neurological dysfunction caused by acute brain circulation loss. It causes acute localized neurological abnormalities such as weakness, sensory deficit, or language issues that require long-term treatment. These deficiencies harm the patient and their family psychologically, socially, and economically. Thus, combination treatment can rapidly rehabilitate such patients. Detoxification methods like Ayurvedic medicated enema help stroke pathophysiology. Physical modalities in physiotherapy have been shown to facilitate normal movement and function on the stroke patient's affected side, increasing independence with everyday duties. A stroke patient may benefit from Dashmoola Niruha Basti, Function Electrical Stimulation (FES), and Motor Relearning Programme (MRP). This study compares the adjuvant role of Dashmoola Basti with MRP and FES in stroke recovery. The main goals of this study are to assess and compare the adjuvant role of Dashmoola Basti with standard control over sensorimotor function of lower extremities, static and dynamic balance in stroke patients; gait parameters; resistance experienced during passive range of motion; quality of life of patients; Barthel Index; Modified Ashworth Scale; and Fuglmeyer assessment, Single Limb Stance Test, Functional Reach Test. A total of 40 patients will be enrolled and divided randomly into two equal groups. In Group A (control), standard treatment (modern + physiotherapy) will be prescribed for one month. In Group B (interventional group), Dashmoola Basti will be added to the aforementioned standard treatment for one month. Improvement in Fuglmeyer assessment, Single Limb Stance Test, Functional Reach Test, quality of Life of Patients, Barthel Index, Modified Ashworth scale, and National Institute of Health (NIH) stroke-scale-score will be observed and recorded. Results and conclusions will be derived according to the data collected in case record form and assessment sheets filled at baseline and follow-up visits. CTRI/2021/10/037445 dated 21.10.2021.

Multimodal brain-controlled system for rehabilitation training: Combining asynchronous online brain–computer interface and exoskeleton

Background:Traditional therapist-based rehabilitation training for patients with movement impairment is laborious and expensive. In order to reduce the cost and improve the treatment effect of rehabilitation, many methods based on human–computer interaction (HCI) technology have been proposed, such as robot-assisted therapy and functional electrical stimulation (FES). However, due to the lack of active participation of brain, these methods have limited effects on the promotion of damaged nerve remodeling. New method:Based on the neurofeedback training provided by the combination of brain–computer interface (BCI) and exoskeleton, this paper proposes a multimodal brain-controlled active rehabilitation system to help improve limb function. The joint control mode of steady-state visual evoked potential (SSVEP) and motor imagery (MI) is adopted to achieve self-paced control and thus maximize the degree of brain involvement, and a requirement selection function based on SSVEP design is added to facilitate communication with aphasia patients. Comparison with existing methods:In addition, the Transformer is introduced as the MI decoder in the asynchronous online BCI to improve the global perception of electroencephalogram (EEG) signals and maintain the sensitivity and efficiency of the system. Results:In two multi-task online experiments for left hand, right hand, foot and idle states, subject achieves 91.25% and 92.50% best accuracy, respectively. Conclusion:Compared with previous studies, this paper aims to establish a high-performance and low-latency brain-controlled rehabilitation system, and provide an independent and autonomous control mode of the brain, so as to improve the effect of neural remodeling. The performance of the proposed method is evaluated through offline and online experiments.

Effects of Functional Electrical Stimulation on Attention and Brain Activity in Healthy Participants Using Near-Infrared Spectroscopy: An Interventional Study

Effects of Functional Electrical Stimulation on Attention and Brain Activity in Healthy Participants Using Near-Infrared Spectroscopy: An Interventional Study

Recognition of Human Lower Limb Motion and Muscle Fatigue Status Using a Wearable FES-sEMG System.

Functional electrical stimulation (FES) devices are widely employed for clinical treatment, rehabilitation, and sports training. However, existing FES devices are inadequate in terms of wearability and cannot recognize a user's intention to move or muscle fatigue. These issues impede the user's ability to incorporate FES devices into their daily life. In response to these issues, this paper introduces a novel wearable FES system based on customized textile electrodes. The system is driven by surface electromyography (sEMG) movement intention. A parallel structured deep learning model based on a wearable FES device is used, which enables the identification of both the type of motion and muscle fatigue status without being affected by electrical stimulation. Five subjects took part in an experiment to test the proposed system, and the results showed that our method achieved a high level of accuracy for lower limb motion recognition and muscle fatigue status detection. The preliminary results presented here prove the effectiveness of the novel wearable FES system in terms of recognizing lower limb motions and muscle fatigue status.

Hypothermia effects on neuronal plasticity post spinal cord injury.

SCI is a time-sensitive debilitating neurological condition without treatment options. Although the central nervous system is not programmed for effective endogenous repairs or regeneration, neuroplasticity partially compensates for the dysfunction consequences of SCI. The purpose of our study is to investigate whether early induction of hypothermia impacts neuronal tissue compensatory mechanisms. Our hypothesis is that although neuroplasticity happens within the neuropathways, both above (forelimbs) and below (hindlimbs) the site of spinal cord injury (SCI), hypothermia further influences the upper limbs' SSEP signals, even when the SCI is mid-thoracic. A total of 30 male and female adult rats are randomly assigned to four groups (n = 7): sham group, control group undergoing only laminectomy, injury group with normothermia (37°C), and injury group with hypothermia (32°C +/-0.5°C). The NYU-Impactor is used to induce mid-thoracic (T8) moderate (12.5 mm) midline contusive injury in rats. Somatosensory evoked potential (SSEP) is an objective and non-invasive procedure to assess the functionality of selective neuropathways. SSEP monitoring of baseline, and on days 4 and 7 post-SCI are performed. Statistical analysis shows that there are significant differences between the SSEP signal amplitudes recorded when stimulating either forelimb in the group of rats with normothermia compared to the rats treated with 2h of hypothermia on day 4 (left forelimb, p = 0.0417 and right forelimb, p = 0.0012) and on day 7 (left forelimb, p = 0.0332 and right forelimb, p = 0.0133) post-SCI. Our results show that the forelimbs SSEP signals from the two groups of injuries with and without hypothermia have statistically significant differences on days 4 and 7. This indicates the neuroprotective effect of early hypothermia and its influences on stimulating further the neuroplasticity within the upper limbs neural network post-SCI. Timely detection of neuroplasticity and identifying the endogenous and exogenous factors have clinical applications in planning a more effective rehabilitation and functional electrical stimulation (FES) interventions in SCI patients.

Joint contact forces during semi-recumbent seated cycling

Semi-recumbent cycling performed from a wheelchair is a popular rehabilitation exercise following spinal cord injury (SCI) and is often paired with functional electrical stimulation. However, biomechanical assessment of this cycling modality is lacking, even in unimpaired populations, hindering the development of personalised and safe rehabilitation programs for those with SCI. This study developed a computational pipeline to determine lower limb kinematics, kinetics, and joint contact forces (JCF) in 11 unimpaired participants during voluntary semi-recumbent cycling using a rehabilitation ergometer. Two cadences (40 and 60 revolutions per minute) and three crank powers (15 W, 30 W, and 45 W) were assessed. A rigid body model of a rehabilitation ergometer was combined with a calibrated electromyogram-informed neuromusculoskeletal model to determine JCF at the hip, knee, and ankle. Joint excursions remained consistent across all cadence and powers, but joint moments and JCF differed between 40 and 60 revolutions per minute, with peak JCF force significantly greater at 40 compared to 60 revolutions per minute for all crank powers. Poor correlations were found between mean crank power and peak JCF across all joints. This study provides foundation data and computational methods to enable further evaluation and optimisation of semi-recumbent cycling for application in rehabilitation after SCI and other neurological disorders.

Functional electrostimulation therapy for vastus medialis decreases the varus thrust during gait.

[Purpose] This study aimed to investigate whether modification of vastus medialis activity can delay the varus thrust. [Participants and Methods] Ten participants (Kellgren-Laurence grades I: n=2, II: n=6, and III: n=2) diagnosed with knee osteoarthritis were enrolled. The intervention involved free walking on a 10-m walkway at any speed after donning a functional electrical stimulation set to contract the vastus medialis before heel contact. Using a Vicon Nexus ground reaction force meter and a wireless electromyograph DELSYS, varus thrust, maximal knee extension angle, maximal knee adduction moment, and vastus medialis onset time were assessed both before and after intervention. [Results] A significant difference in varus thrust was detected from before to after the intervention (2.7 ± 1.1° vs. 2.2 ± 1.3°). Both the vastus medialis activation time (-0.06 ± 0.09 vs. -0.21 ± 0.1) and the knee-joint extension angle (8.7 ± 5.1° vs. 5.5 ± 5.9°) decreased following intervention, whereas the knee adduction moment significantly increased (0.50 ± 0.20° vs 0.56 ± 0.18°). [Conclusion] Wearing the functional electrical stimulation set caused the vastus medialis to act earlier in response to heel strike, thereby improving the knee-joint extension angle and suppressing varus thrust.

Development of a functional electrical stimulation cycling toolkit for spinal cord injury rehabilitation in acute care hospitals: a participatory action approach

Development of a functional electrical stimulation cycling toolkit for spinal cord injury rehabilitation in acute care hospitals: a participatory action approach

Determination of Optimal Conditions for Neuroprosthetic Functional Electrical Stimulation Therapy to Produce Wrist Dorsiflexion Movements Using the Versatility Index

Determination of Optimal Conditions for Neuroprosthetic Functional Electrical Stimulation Therapy to Produce Wrist Dorsiflexion Movements Using the Versatility Index

Results of functional electrical stimulation of leg muscles during walking in a patient in the early recovery period after a stroke

Acute cerebrovascular accident throughout the world remains the main cause of subsequent disability in persons who have suffered a stroke.
 One promising area is neuromuscular stimulation. Functional electrical stimulation is a subtype of neuromuscular stimulation in which stimulation promotes functional and goal-oriented movements in the individual.
 A course of functional electrical stimulation was administered while walking to a 74-year-old patient in the late recovery period of an ischemic stroke (the right middle cerebral artery). 14 procedures were performed lasting from 20 to 30 minutes. Before and after the functional electrical stimulation course, a clinical study and a study of the biomechanics of walking were conducted.
 The results obtained showed an improvement in clinical indicators, inconsistent changes in the time parameters of the step cycle, an increase in amplitudes in the hip and knee joints, as well as normalization of the function of the knee and ankle joints of the paretic side. Functional EMG research showed both an improvement in muscle activity and normalization of their activity profile, as well as processes of function restructuring that require further study.
 During functional electrical stimulation, there were no negative reactions from the patient or irritation of the skin at the locations of the electrodes.
 The method of functional electrical stimulation requires further study and reasonable application in this category of patients.

Weft-Knitted Strain Sensors for Motion Capture

Motion capture, especially of the knee angle, is an important component for situational triggering of functional electrical stimulation (FES). One major disadvantage of commercial FES devices is their bulky design that prevents unobtrusive wearing in everyday life and limits the patient’s free choice of appearance. This paper presents an alternative approach of sensors for motion capture in form of textile-based strain sensors. These can be integrated in a FES system in form of functional leggings, which make the FES system suitable for an unobtrusive daily use. Textile sensors, especially knitted sensors have already proven to be very promising to detect tensile strain. In particular, weft-knitted strain sensors, which can be integrated directly into the clothing during the knitting process, have the potential to detect the knee angle and therefore derive the gait phase due to the bending of the limbs without disturbing the wearer unnecessarily. Different designs of the weft-knitted strain sensor and their influence on the measurement behaviour of the sensor have been investigated. The weft-knitted strain sensor can be directly integrated in the knee area of the functional leggings to be used as a soft trigger to initiate electrical impulses for FES.

Ineffective voluntary motor improvement through non-invasive BCI-FES with static magnetic field in complete spinal cord injury: A pilot study

In response to the challenge of spinal cord injury (SCI) rehabilitation, this study aimed to investigate the effect of applying a non-invasive interface of surface neuroelectrical signals and functional electrical stimulation (sNES-sFES) with a static magnetic field on the motor outcome of the quadriceps femoris muscle in an individual with a complete SCI. The participant, who had a complete SCI in the chronic stage, was evaluated before (pre) and after nine (post) interventions using surface electromyography (sEMG). In addition, spasticity (modified Ashworth scale [MAS]) was observed in all sessions. Moreover, the user learning curve process (classifier percentage and correct success of the sFES hits) was evaluated. In general, we observed: (i) No voluntary muscle contraction (pre- and post-root mean square of sEMG = 0%) improvement; (ii) spasticity decrease (average one point in MAS); (iii) gradual improvement in the user learning effect on the interface, reaching 84% in classifier accuracy and a maximum percentage of correct sFES activation of 53%. In conclusion, no improvement in voluntary muscular contraction was observed within 9 weeks of the intervention (1 session/day; 1 h/week). However, our study demonstrates the safety and feasibility of our methodology for future research involving continuous physical rehabilitation training and the implementation of assistive technology.

Deep Learning-based Thigh Muscle Investigation Using MRI For Prosthetic Development for Patients Undergoing Total Knee Replacement (TKR).

A prosthetic device is designed based on the quantitative analysis of muscle MRI which will improve the muscle control achieved with functional electrical stimulation/ guided robotic exoskeletons. Electromyography (EMG) provides muscle functionality information while MRI provides the physiological and functionality of muscles. The sensor feedbacks were used for the bionic prosthesis, but the length of muscle using image processing was not correlated. To investigate and perform qualitative and quantitative assessment of thigh muscle using MRI. The objective of the work is to improve the existing VAG signal classification method to diagnose abnormality using MRI for patients undergoing Total knee replacement (TKR). A deep learning method for qualitative and quantitative assessment of thigh muscle is done using MRI. In existing prosthetic devices, electrical measurements of a person's muscles are obtained using surface or implantable electrodes. Several methods were used for the classification and diagnostic processes. The existing methods have drawbacks in feature extraction and require experts to design the system. This work combines medical image processing and orthopaedic prosthetics to develop a therapeutic method. This design provides much more precise control of prosthetic limbs using the image processing technique. The hybrid CNN swarm-based method measures the muscle structure and functions. Along with the sensor readings, these details are combined for prosthetic control. The implementation was carried out in MATLAB, Sketchuppro, and Arduino IDE. A combined swarm intelligence and deep learning method were proposed for qualitative and quantitative assessment of thigh muscle. The prosthetic device choice was done from the scanned MRI image like Humerus-T prosthetics, segmental prosthesis and arthrodesis prosthesis. The investigation was done for the Total knee replacement (TKR) approach.

Functional electrical stimulation combined with voluntary cycling accentuates VO2 response in people with severe multiple sclerosis: A pilot study

BackgroundLower limb muscle weakness and reduced balance due to disease progression in multiple sclerosis (MS) may make robust aerobic exercise difficult. Functional electrical stimulation (FES) cycling combined with voluntary cycling may allow people with severe MS to enhance the intensity of aerobic exercise. The aim of this study was to investigate the cardiorespiratory, power, and participant-reported perceptions during acute bouts of FES cycling, voluntary cycling, and FES cycling combined with voluntary cycling (FES assist cycling). MethodsParticipants with severe MS (Expanded Disability Status Scale [EDSS] ≥ 6.0) undertook three exercise trials on a leg cycle ergometer. Trial 1 involved 30 min of FES cycling; Trial 2 involved two 10-minute bouts of voluntary cycling separated by 10 min rest; and Trial 3 was a combination of trials 1 and 2 (FES assist cycling). Outcome measures included VO2 (volume of oxygen consumption), cycle power output, heart rate, RPE, and post-exercise perceptions of pain and fatigue. ResultsTen people with severe MS participated (9 female; age 52.4 ± 9.98 y; EDSS 7.1 ± 0.6). The average VO2 during the 30-minute trials was significantly higher for FES assist cycling compared to voluntary cycling (429.7 ± 111.0 vs 388.5 ± 101.0 mL/min, 95% CI 23.4 to 113.0 mL/min, p = 0.01), with a large effect size (Hedges' g = 1.04). Participants reported similar rates of perceived exertion at the end of FES cycling (13 ± 2), voluntary cycling (14 ± 2), and FES assist cycling (15 ± 1); p = 0.14. Self-reported pain was higher during both FES cycling (5.4 vs 0.3; 95% CI 3.4 to 6.7, p = 0.01, Hedges’ g = 2.07) and FES assist cycling (4.2 vs. 0.3; 95% CI 2.3 to 5.5, p = 0.01, Hedges’ g = 1.71) than voluntary cycling, both with large effect sizes. There was no difference in self-reported fatigue at the end of each trial (p = 0.21). ConclusionThis study found FES assist cycling produced significantly higher VO2 values than voluntary cycling, although the clinical significance of these differences is unknown. Participants performed FES assist cycling at a self-reported RPE consistent with moderate to vigorous intensity, however it was considered light-intensity exercise when expressed by METS. FES assist cycling was no more fatiguing post-exercise than the other modes.

Effects of releasing ankle joint during electrically evoked cycling in persons with motor complete spinal cord injury.

Literature has shown that simulated power production during conventional functional electrical stimulation (FES) cycling was improved by 14% by releasing the ankle joint from a fixed ankle setup and with the stimulation of the tibialis anterior and triceps surae. This study aims to investigate the effect of releasing the ankle joint on the pedal power production during FES cycling in persons with spinal cord injury (SCI). Seven persons with motor complete SCI participated in this study. All participants performed 1min of fixed-ankle and 1min of free-ankle FES cycling with two stimulation modes. In mode 1 participants performed FES-evoked cycling with the stimulation of quadriceps and hamstring muscles only (QH stimulation), while Mode 2 had stimulation of quadriceps, hamstring, tibialis anterior, and triceps surae muscles (QHT stimulation). The order of each trial was randomized in each participant. Free-ankle FES cycling offered greater ankle plantar- and dorsiflexion movement at specific slices of 20° crank angle intervals compared to fixed-ankle. There were significant differences in the mean and peak normalized pedal power outputs (POs) [F(1,500) = 14.03, p < 0.01 and F(1,500) = 7.111, p = 0.008, respectively] between fixed- and free-ankle QH stimulation, and fixed- and free-ankle QHT stimulation. Fixed-ankle QHT stimulation elevated the peak normalized pedal PO by 14.5% more than free-ankle QH stimulation. Releasing the ankle joint while providing no stimulation to the triceps surae and tibialis anterior reduces power output. The findings of this study suggest that QHT stimulation is necessary during free-ankle FES cycling to maintain power production as fixed-ankle.

Rehabilitation effect of core muscle training combined with functional electrical stimulation on lower limb motor and balance functions in stroke patients.

Studies have shown that core muscle training can accelerate the recovery of motor function in stroke patients. However, there are no relevant reports to show the effect of core muscle training combined with functional electrical stimulation (FES) on the rehabilitation of stroke patients. This study aimed to observe the efficacy of core muscle training combined with FES on motor and balance functions of lower limbs in stroke patients. This study selected and divided 120 stroke patients with hemiplegia admitted to our hospital into the control and observation groups. Patients in the control group just received core muscle training; while patients in the observation group were treated by core muscle training combined with FES. Both groups were treated for 8 weeks. Subsequently, the clinical data and information of all patients were collected and counted. Muscle strength changes were observed by detecting paralytic dorsiflexor (pDF), plantar flexor (pPF), knee extensor (pKE), and knee flexor (pKF) before and after treatment. Motor and balance abilities of both groups were scored through the 10-meter walking test (10 MWT), Berg balance scale (BBS), functional ambulation category (FAC) scale, timed up and go (TUG) test, and lower extremity motricity index (MI-Lower). No significant difference was found in clinical data between the two groups. The intensity of pDF, pPF, pKE, and pKF significantly increased in both groups after treatment, and the intensity of these parameters was higher in the observation group relative to the control group. Additionally, 10 MWT and TUG test scores of patients in the observation group were notably decreased while the BBS and MI-Lower scores were significantly increased after treatment compared with those in the control group. Core muscle training combined with FES can significantly improve the rehabilitation effect of lower limb motor and balance functions in stroke patients.

Case Analysis on Three Methods of BCI Systems for Stroke Rehabilitation

Stroke is a disease that can cause disability to patients, and many people suffer from stroke. Brain-computer interface (BCI) technology development leads to BCI stroke rehabilitation system. After several years of development of theory and technology, BCI systems show great potential in stroke rehabilitation. There are three specific methods of BCI stroke rehabilitation systems. The methods involve Functional Electric Stimulation, Robotics Assisted Systems, and Virtual Reality. This paper will introduce three methods and analyze the research cases of each technique. The article will introduce the principle and investigate some research cases of each method. The paper will present the procedure, analyze the results and evaluate each experiment. By analyzing the cases, it can be learned that all three methods are feasible and effective, proving that the BCI system for stroke rehabilitation is a promising therapy. At last, limitations on BCI systems will be analyzed, such as small sample size and limitations on particular actions.

Four-compartment muscle fatigue model to predict metabolic inhibition and long-lasting nonmetabolic components.

Introduction: Computational muscle force models aim to mathematically represent the mechanics of movement and the factors influencing force generation. These tools allow the prediction of the nonlinear and task-related muscle behavior, aiding biomechanics, sports science, and rehabilitation. Despite often overlooking muscle fatigue in low-force scenarios, these simulations are crucial for high-intensity activities where fatigue and force loss play a significant role. Applications include functional electrical stimulation, motor control, and ergonomic considerations in diverse contexts, encompassing rehabilitation and the prevention of injuries in sports and workplaces. Methods: In this work, the authors enhance the pre-existing 3CCr muscle fatigue model by introducing an additional component of force decay associated with central fatigue and a long-term fatigue state. The innovative four-compartment model distinguishes between the short-term fatigued state (related to metabolic inhibition) and the long-term fatigued state (emulating central fatigue and potential microtraumas). Results: Its validation process involved experimental measurements during both short- and long-duration exercises, shedding light on the limitations of the traditional 3CCr in addressing dynamic force profiles.

Upper extremity training followed by lower extremity training with a brain-computer interface rehabilitation system.

Brain-computer interfaces (BCIs) based on functional electrical stimulation have been used for upper extremity motor rehabilitation after stroke. However, little is known about their efficacy for multiple BCI treatments. In this study, 19 stroke patients participated in 25 upper extremity followed by 25 lower extremity BCI training sessions. Patients' functional state was assessed using two sets of clinical scales for the two BCI treatments. The Upper Extremity Fugl-Meyer Assessment (FMA-UE) and the 10-Meter Walk Test (10MWT) were the primary outcome measures for the upper and lower extremity BCI treatments, respectively. Patients' motor function as assessed by the FMA-UE improved by an average of 4.2 points (p < 0.001) following upper extremity BCI treatment. In addition, improvements in activities of daily living and clinically relevant improvements in hand and finger spasticity were observed. Patients showed further improvements after the lower extremity BCI treatment, with walking speed as measured by the 10MWT increasing by 0.15 m/s (p = 0.001), reflecting a substantial meaningful change. Furthermore, a clinically relevant improvement in ankle spasticity and balance and mobility were observed. The results of the current study provide evidence that both upper and lower extremity BCI treatments, as well as their combination, are effective in facilitating functional improvements after stroke. In addition, and most importantly improvements did not stop after the first 25 upper extremity BCI sessions.