One study has examined pulse durations in dogs and subsequently recommended pulse durations by individual muscles Table This study also examined the differences in needed pulse durations between people and dogs.
Although they are similar, dogs in general do not require as long a pulse duration as human motor nerves to depolarize. This can potentially increase comfort by using the shortest recommended pulse duration. This range facilitates the selection of a single chronaxy value when stimulating several muscles in 1 region. Am J Vet Res , Pulse rate also called frequency, rate and pulses per second [pps] is the number of pulses delivered per second and is measured in hertz Hz.
However, as frequency increases the rate of fatigue also increases. Duty cycle is the ratio of on-time to total cycle time, expressed as a percentage Figure On-time is the period of time in which a series of pulses or bursts are delivered to the patient. Off-time is the time between on-times. A single on-time duration plus a single off-time duration constitutes the total cycle time.
As on-time increases, muscle fatigue increases. A patient with severe atrophy may require a longer off-time to recover between contractions. Many clinicians start with duty cycle ratios between 1 : 2 and 1 : 5 and watch for signs of fatigue, which indicates the need for a longer off-time. Ramp is a feature of NMES that helps improve patient comfort. It involves a gradual increase or decrease in current amplitude such that the number of recruited motor units gradually increases the force of muscle contraction or gradually decreases the force of contraction Figure The ramp time is the period of time over which the pulse is increasing or decreasing.
No data to date have identified the optimal ramp time. However, a ramp up time of 2 to 4 seconds is commonly used to maximize comfort with a 1- to 2-second ramp down. Box Current Parameters for Strengthening. These have been shown in humans to produce strong tetanic contractions while minimizing fatigue. This will provide a twitch contraction and is better tolerated in some cases. Waveforms: Many waveforms exist; any waveform capable of depolarizing the muscle is acceptable.
Pulse or phase duration: Between and microseconds. This may be decreased as muscle strength improves. A 1 : 1 or 1 : 2 ratio is usually used for muscle endurance training. Many types of surface electrodes are available. The main criteria in choosing electrodes are as follows:. Flexible enough to conform to the tissue. Some commercially available electrodes are effective for only a few uses, and some may be used or more times e.
Conductive performance of any electrode decreases over time. Electrodes require a medium to transmit current. Commonly used media include gels, moistened sponges or paper towels; some electrodes have the media already applied. Sponges and paper towels tend to dry out, and rewetting is necessary every 30 minutes. Electrodes should be of the appropriate size to stimulate the desired muscle without stimulating unwanted muscles in close proximity. The smaller the electrode, the higher the current density that enters the muscle, and the more uncomfortable the stimulus may be.
An alternative to traditional electrodes is the use of electrodes with multiple fine wires or prongs that make contact with the skin see Fig. The advantage of these types of electrodes is that the hair does not need to be clipped. Rather the fine wire prongs are worked down among the hair to contact the skin.
Wetting the hair before treatment helps with conductivity. Neuromuscular electrical stimulators recruit Type II fast twitch fibers first, then Type I slow twitch , which is the reverse of the muscle recruitment pattern in a volitional contraction. Increasing either the amplitude or the pulse duration affects the strength of contraction because additional muscle fibers are recruited.
Increasing the frequency results in the existing motor units firing at a faster rate and will increase the strength of contraction, but it also causes more rapid fatigue. Application of NMES at an optimal frequency results in an optimal physiologic response the desired contraction while minimizing fatigue.
In a healthy uninjured individual, a maximal voluntary muscle contraction produces a greater torque more powerful contraction than occurs in an electrically induced contraction. However, patients with injuries or immediately following surgery may be unable or unwilling to produce a maximum voluntary muscle contraction. In these patients NMES may produce a stronger muscle contraction.
Textile-based neuroprostheses. The garment includes rectangular areas dark grey patches made of conductive yarn that function as electrodes. Details can be found in [ 65 ]. Despite the demonstrated feasibility of using textile-based electrodes to deliver FES, one important aspect that is being investigated is the comfort of the individual receiving the stimulation using this technology.
Zhou et al. In their study, they found a wet textile-based electrode was able to produce movement, similar to a hydrogel, while applying stimulation with a dry textile-base electrode produced pain even at low stimulation currents. Similar observations were reported by [ 65 ] when using their garments for FES delivery.
FES has provided tangible assistance to individuals with mobility impairments for decades. The technology has allowed participation in daily life which otherwise would be difficult or impossible. Today, FEST is an important tool available to therapists working in the field of neurorehabilitation. The evolution of the technology has facilitated its use in clinical environments and has already produced some of the largest improvements in motor function of individuals with stroke and SCI.
The prevalence of FEST will likely increase in the next decade with an expected increase in the aging population; age is a risk factor of stroke. It is possible that with this change in demographics, the emphasis of stroke care will change to continue to include prevention and cure, with a newly increased focus on rehabilitation as well [ 68 ].
Significant challenges lie ahead including increasing the efficacy of FEST as well as its adoption. Currently, the majority of FES systems still require that users delivering the intervention have knowledge of functional anatomy, as well as the effects of each of the stimulation parameters on the contraction produced by the stimulation.
New technologies will play a fundamental role in a larger adoption of FES. Inclusion of new stimulation form factors, such as the wearable systems described here, along with automatic optimization of stimulator parameters will likely play a central role in the increased use of FEST. In addition, the combination of FEST, along with the further inclusion of new understanding of the neuroplastic basis of motor learning, provides an opportunity to see further increases in the efficacy of this intervention.
Dayan E, Cohen LG. Neuroplasticity subserving motor skill learning. Article Google Scholar. Functional electrical stimulation: a review of the literature published on common peroneal nerve stimulation for the correction of dropped foot. Rev Clin Gerontol. Therapeutic electrical stimulation to improve motor control and functional abilities of the upper extremity after stroke: a systematic review.
Clin Rehabil. Effectiveness of upper limb functional electrical stimulation after stroke for the improvement of activities of daily living and motor function: a systematic review and meta-analysis. Syst Rev. Baker LL. Neuromuscular electrical stimulation: a practical guide. Neural prostheses: replacing motor function after disease or disability. Oxford: Oxford University Press; Google Scholar. Surface-stimulation technology for grasping and walking neuroprostheses.
Recent applications of functional electrical stimulation to stroke patients in Ljubljana. Clin Orthop Relat Res. Hoshimiya N. A master—slave type multichannel functional electrical stimulation FES system for the control of the paralyzed upper extremities. A flexible, portable system for neuromuscular stimulation in the paralyzed upper extremity. The bionic glove: an electrical stimulator garment that provides controlled grasp and hand opening in quadriplegia. Arch Phys Med Rehabil.
The NESS handmaster orthosis: restoration of hand function in C5 and stroke patients by means of electrical stimulation. J Rehabil Sci. Hybrid FES orthosis incorporating closed loop control and sensory feedback. J Biomed Eng. Hybrid assistive system—the motor neuroprosthesis.
Standing and walking after spinal cord injury: experience with the reciprocating gait orthosis powered by electrical muscle stimulation. Top Spinal Cord Inj Rehabil. Implanted functional neuromuscular stimulation systems for individuals with cervical spinal cord injuries: clinical case reports.
Principles of neural science. Popovic MR, Keller T. Modular transcutaneous functional electrical stimulation system. Med Eng Phys. Examining a new functional electrical stimulation therapy with people with severe upper extremity hemiparesis and chronic stroke: a feasibility study. Br J Occup Ther.
Liberson WT. Functional electrotherapy: stimulation of the peroneal nerve synchronized with the swing phase of the gait of hemiplegic patients. Arch Phys Med. Clinical use of the Odstock dropped foot stimulator: its effect on the speed and effort of walking. An implantable two channel drop foot stimulator: initial clinical results. Artif Organs. Phase II trial to evaluate the ActiGait implanted drop-foot stimulator in established hemiplegia.
J Rehabil Med. Hausdorff JM, Ring H. Effects of a new radio frequency controlled neuroprosthesis on gait symmetry and rhythmicity in patients with chronic hemiparesis. Am J Phys Med Rehabil. Long-term therapeutic and orthotic effects of a foot drop stimulator on walking performance in progressive and nonprogressive neurological disorders.
Neurorehabil Neural Repair. Enhancement of gait restoration in spinal injured patients by functional electrical stimulation. The RGO generation II: muscle stimulation powered orthosis as a practical walking system for thoracic paraplegics. Graupe D, Kohn KH. Functional neuromuscular stimulator for short-distance ambulation by certain thoracic-level spinal-cord-injured paraplegics.
Surg Neurol. Gait training regimen for incomplete spinal cord injury using functional electrical stimulation. Spinal Cord. Rebersek S, Vodovnik L. Proportionally controlled functional electrical stimulation of hand. An externally powered, multichannel, implantable stimulator-telemeter for control of paralyzed muscle. A programmable electronic stimulator for FES systems. Vodovnik L. Therapeutic effects of functional electrical stimulation of extremities.
Med Biol Eng Comput. Electrical stimulation and feedback training: effects on the voluntary control of paretic muscles. Why is functional electrical stimulation therapy capable of restoring motor function following severe injury to the central nervous system?
In: Translational neuroscience. Boston: Springer US; , pp. A control study of muscle force recovery in hemiparetic patients during treatment with functional electrical stimulation.
Scand J Rehabil Med. Use of functional electrical stimulation in the lower extremities of incomplete spinal cord injured patients. A randomized trial of functional electrical stimulation for walking in incomplete spinal cord injury: effects on walking competency. J Spinal Cord Med. Functional electrostimulation in poststroke rehabilitation: a meta-analysis of the randomized controlled trials. Neuromuscular stimulation for upper extremity motor and functional recovery in acute hemiplegia.
Cauraugh JH, Kim S. Two coupled motor recovery protocols are better than one: electromyogram-triggered neuromuscular stimulation and bilateral movements. Therapy of paretic arm in hemiplegic subjects augmented with a neural prosthesis: a cross-over study.
Can J Physiol Pharmacol. Neuroprosthesis for retraining reaching and grasping functions in severe hemiplegic patients. Neuromodul J Int Neuromodul Soc. Upper-extremity functional electric stimulation-assisted exercises on a workstation in the subacute phase of stroke recovery.
Rehabilitation of reaching and grasping function in severe hemiplegic patients using functional electrical stimulation therapy. Chae J, Hart R. Intramuscular hand neuroprosthesis for chronic stroke survivors.
Gritsenko V, Prochazka A. A functional electric stimulation-assisted exercise therapy system for hemiplegic hand function. A home program of sensory and neuromuscular electrical stimulation with upper-limb task practice in a patient 5 years after a stroke. Phys Ther. Intramuscular electrical stimulation for upper limb recovery in chronic hemiparesis: an exploratory randomized clinical trial. Functional electrical stimulation therapy for recovery of reaching and grasping in severe chronic pediatric stroke patients.
J Child Neurol. Clinical evaluation of the bionic glove. Transcutaneous functional electrical stimulation for grasping in subjects with cervical spinal cord injury.
Functional electrical stimulation therapy of voluntary grasping versus only conventional rehabilitation for patients with subacute incomplete tetraplegia: a randomized clinical trial. Restoring voluntary grasping function in individuals with incomplete chronic spinal cord injury: pilot study.
Brain—computer interfaces in neurological rehabilitation. Lancet Neurol. Neurosci Lett. EEG-based neuroprosthesis control: a step towards clinical practice. Control of a neuroprosthesis for grasping using off-line classification of electrocorticographic signals: case study. Feasibility of a new application of noninvasive brain computer interface BCI : a case study of training for recovery of volitional motor control after stroke.
J Neurol Phys Ther. EEG-triggered functional electrical stimulation therapy for restoring upper limb function in chronic stroke with severe hemiplegia. Case Rep Neurol Med. Restoration of upper-limb function after chronic severe hemiplegia: a case report on the feasibility of a brain-computer interface controlled functional electrical stimulation therapy. Stimulating the comfort of textile electrodes in wearable neuromuscular electrical stimulation. Garments for functional electrical stimulation: design and proofs of concept.
J Rehabil Assist Technol Eng. Advances in selective activation of muscles for non-invasive motor neuroprostheses. J NeuroEng Rehabil. Screen printed fabric electrode array for wearable functional electrical stimulation.
Sens Actuators A. The next revolution in stroke care. Expert Rev Neurother. Download references. You can also search for this author in PubMed Google Scholar. All authors read and approved the final manuscript. Correspondence to Cesar Marquez-Chin. Milos R. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material.
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BioMed Eng OnLine 19, 34 Download citation. Received : 09 January Accepted : 25 April Published : 24 May Anyone you share the following link with will be able to read this content:.
Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative. Skip to main content. Search all BMC articles Search. Download PDF. Abstract Functional electrical stimulation is a technique to produce functional movements after paralysis. Background Losing the ability to move voluntarily can have devastating consequences for the independence and quality of life of a person.
Stroke Stroke is the fifth cause of death in the United States and a leading cause of disability [ 5 ]. Rehabilitation after stroke and SCI Recovering voluntary motor function can improve the independence and quality of life after stroke and SCI.
Functional electrical stimulation Electrical current can elicit a response in excitable cells including neurons. Neuromuscular stimulation Neuromuscular stimulation NMES is one application of electrical stimulation used in rehabilitation of movement. Functional electrical stimulation Functional electrical stimulation FES is a subtype of NMES in which the stimulation assists functional and purposeful movements. Components of a neuroprosthesis The basic components of a neuroprosthesis are an electrical stimulator, electrodes that deliver the stimulation, sensors for user or automatic control of the stimulation, and in some cases, an orthosis that provides additional assistance to perform the desired movement [ 7 ].
Electrical stimulator The electrical stimulator is responsible for generating the electrical discharges that produce muscle contractions. Stimulation electrodes Electrical stimulation can be delivered using electrodes with different levels of invasiveness; they can be completely or partially implanted, known as implanted and percutaneous electrodes, respectively, or can also be placed on the surface of the body transcutaneous or noninvasive electrodes.
Table 1 Stimulation electrodes with different levels of invasiveness Full size table. Stimulation intensity: pulse amplitude and duration The intensity of the stimulation is determined by three parameters: pulse amplitude, pulse duration and pulse frequency Fig.
Full size image. Examples of commonly used pulse shapes used for functional electrical stimulation. Electrode placement The location of the stimulating electrodes has a direct impact on the muscles that are stimulated and, consequently, on the movements that are produced. Intensity of the stimulation setting The intensity of the stimulation will determine which muscles are contracted as well as the strength of their contraction.
These include 1. Clinical considerations for the use of electrical stimulation Delivery of electrical pulses may affect tissue beyond the intended muscle with unexpected consequences.
For this reason, it is important to mention a few important considerations and precautions prior to using electrical stimulation: Poor skin condition: Pressure injuries a. Pregnancy: The effect of FES on the unborn child is not known in pregnancy. Clinical applications of FES FES has been used clinically as both an assistive device and a therapeutic intervention to facilitate restoration of volitional movement.
Functional electrical stimulation as an assistive device One of the original motivations for the development of FES technology was to compensate for lost function. During the 19th century, using neurostimulation therapies was particularly popular among German psychiatrists, who pioneered electrotherapy as an early form of tDCS.
At the same time, several scientists pursued further research on the use of direct current for treating mental disorders but the great variety of methods, the lack of clarity in the descriptions and, in general, the misunderstanding of the effects and operating principles led to inconclusive or contradictory results. As a consequence, the use of direct current stimulation and research was abandoned by the s in favor of electroconvulsive therapy ECT.
The birth of the modern neuromodulation era can be placed at the turn of the millennium, when a search for new therapies to effectively treat mental disorder with non-invasive, well tolerated methods with fewer side effects sparked great interest, and studies on the influence of direct current on cerebral cortex excitability were further researched.
Nowadays, technological and engineering advances have made possible the development of very accurate neuromodulation instruments. The advances in the hardware, combined with the better understanding of the effects of electrical currents on the brain, and the abundance of systematic, randomised controlled trials carried out, has allowed neuroscientists, clinical neurologists and psychiatrists to use tDCS as a safe and effective method to treat neuropathic and neuropsychiatric conditions such as chronic pain, migraine or major depressive disorder.
The scientific community is still working on their findings, some of which require further research. A proper diagnosis and therapy protocol must be established prior to the treatment to achieve the best possible result.
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