Glossary

FES Glossary

Words and phrases starting with:
A B C D E F G H I J K L M N O P Q R S T U V W

A

Accepted practice

Characterized by widely available commercial systems, regular prescription by health care providers, and coverage for the treatment and devices by medical insurance companies.

Activation

See Stimulation.

Activities of daily living (ADL)

Day-to-day tasks that must be performed by an individual or a personal assistant; e.g., bathing, dressing, and eating.

Afferent

Conveying nerve impulses toward the brain or spinal column. See also Efferent.

AFO

See Ankle foot orthosis.

Agonist

A contracting muscle whose contraction is opposed by another muscle. See also Antagonist.

ALS

See Amyotrophic lateral sclerosis.

Alternating Current (AC)

The uninterrupted bi-directional flow of charged particles. May be symmetrical or asymmetrical. May refer to a type of stimulation current. See also Direct current.

Ambulation

See Gait.

Amyotrophic lateral sclerosis (ALS)

A disease of the upper and lower motor neurons; its cause is unknown. The disease arises from gradual degeneration of cells in the brain and spinal cord which leads to muscle paralysis. Also known as Lou Gehrig’s Disease.

Anal stimulation

Delivery of electrical pulses through an electrode inserted into the anus to activate the surrounding nerve tissue, typically to provide continence. See also Bowel evacuation; Electroejaculation.

Animal models

The use of animals to evaluate FES techniques prior to implementation of clinical evaluations. Useful for enhancing, fine-tuning, and determining the safety and efficacy of electrical stimulation techniques.

Ankle foot orthosis (AFO)

A brace worn on the foot to stabilize movement or limit rotation of the foot about the ankle.

Anode

The electrically positive electrode required in a stimulation system to form a complete path for current to travel through the body part of interest. Anodes may be shared between stimulus channels. See also Cathode.

Antagonist

The muscle which exerts an opposite action to that of another muscle. See also Agonist.

Applied neural control

The body of knowledge associated with the development of technology and devices based on the electrical excitability of nerves.

ASIA impairment scale

As defined by the American Spinal Injury Association, a method for describing the deficit that results from a spinal injury.

A = Complete

No motor or sensory function is preserved in sacral segments S4-S5.

B = Incomplete

Sensory but not motor function is preserved below the neurological level and extends through S5-S5.

C = Incomplete

Motor function is preserved below the neurological level, and the majority of key muscles below the neurological level have a muscle grade less than 3

D = Incomplete

Motor function is preserved below the neurological level, and the majority of key muscles below the neurological level have a muscle grade greater than or equal to 3

E = Normal

Motor and sensory function are normal.

Assistive technology

See Rehabilitation technology.

Atrophy

Reduction in size of a muscle or muscle group because of disease or disuse. See also Hypertrophy.

Autonomic dysreflexia

Sudden onset of high blood pressure, slow heartbeat, sweating and severe headache.

Axon

The central core of a nerve fiber. See also Nerve.

B

Basic research

A stage of development of FES that investigates neurophysiological phenomena using computer and animal models.

Bed sore

See Decubitus ulcer.

Bicycle ergometry

The use of electrical stimulation to cause movement of the leg muscles against loaded bicycle pedals. Commercial FES cycling systems are available.

Biofeedback

The technique of making unconscious or involuntary bodily processes perceptible to the conscious mind in order to manipulate them by conscious mental control. Typically, EMG (electromyogram) biofeedback is used with FES to facilitate muscle contraction.

Biomedical engineering

The application of engineering principles to biology and medicine.

Bladder evacuation

The process of emptying the bladder or urination. May be enhanced by using electrical stimulation to contract the bladder and force the contents out, thereby reducing the risk of residual urine which may lead to serious infection. See also Penile erection.

Bladder function

The role of the bladder in evacuating urine (micturition) and the role of the urinary sphincters in preventing the evacuation of urine. Lack of sphincter control is known as incontinence. See also Incontinence; Micturition.

Bone stress

A condition caused by external force applied to the bone; excess force could cause bone fracture.

Bowel evacuation

The process of emptying the bowels. May be enhanced by applying electrical stimulation to specific skin areas of the low back (lumbar and sacral dermatomes) if voluntary control of the bowel has been lost. See also Penile erection.

C

Candidate referral

The process by which an individual is referred to an electrical stimulation program on the basis of program type, medical condition, geographic location, etc.

Cardiovascular exercise.

A stage of exercise during which the heart rate is raised to a level sufficient to improve fitness. May be induced using electrical stimulation to contract muscles, as in bicycle ergometry.

CARF

Commission on the Accreditation of Rehabilitation Facilities.

Cathode

An electrically negative electrode. One cathode is required in a stimulation system for each muscle or nerve group to be activated. See also Anode.

Central nervous system (CNS)

The part of the nervous system comprising the brain and spinal cord. Diseases of the CNS include cerebral palsy, multiple sclerosis, spinal cord injury, stroke, and head injury.

Cerebellar stimulation

Activation of cells in the part of the brain which monitors motor function, the cerebellum.

Cerebrovascular accident (CVA)

See Stroke.

CFES

See Computerized Functional Electrical Stimulation.

Channel

A specification of electrical stimulators, referring to the number of separate nerve/muscle groups which can be activated by the stimulator. Each channel requires an anode-cathode electrical pair.

Circulatory pooling

Collection of the blood due to inadequate circulation. May be reduced by the use of electrical stimulation to muscles in the vicinity of the pooling to produce a pumping action.

Clinical research

The stage of development of FES at which techniques are being evaluated in small numbers of human subjects, as opposed to animal or computer models. Also called clinical feasibility studies. Preceded by basic research.

Clinical service

In theory, any use of FES offered as a service, typically for a fee, that is not in any way considered experimental. In practice, certain aspects of the treatment may in fact be experimental.

Closed-loop control

See Control.

CNS

See Central nervous system.

Command

The signal whose value determines the onset, duration, and level of stimulus applied.

Complete spinal lesion

An injury to the spinal cord that prohibits transmission of all signals between the brain and the peripheral nerves. Results in total loss of muscle power and sensation below the level of injury. See also Incomplete spinal lesion.

Computerized Functional Electrical Stimulation (CFES)

The control of stimulation parameters by a computer. Often used to describe FES cycling systems.

Computerized muscle stimulation

Use of a computer or microprocessor to generate complex stimulation patterns applied to a muscle or muscles.

Contraction

The shortening of muscle fibers due to activation of a muscle by voluntary or external means.

Contracture

See Joint contracture.

Control

Mechanisms that vary stimulus parameters to a muscle to regulate function. Open-loop control mechanisms use a pre-set relationship between the command input and the stimulus output. Closed-loop control mechanisms can vary the relationship between command input and stimulus output according to feedback signals. Such signals contain information about quantities such as force or position.

Cortical stimulation.

Activation of brain cells in the cerebral cortex which process thought, motor, and sensory information.

Cuff electrode

An electrode that wraps partly or entirely around a nerve. Usually made of a soft material with embedded metal contacts.

D

Decubitus ulcer

An inflammation or sore in the skin over a prominent bone. Results from lack of circulation to the area due to prolonged pressure or restricted blood supply (ischemia). Also known as bed sores, pressure sores, or ischemic sores.

Deep venous thrombosis

Blood clotting in the deep veins in the legs.

Denervation

A condition in which the activation path between a nerve and muscle is no longer working due to peripheral nerve trauma or central nervous system disease, causing lower motor neuron damage. The condition results in muscle atrophy and often causes muscle contractures. As a short term therapeutic treatment, denervated muscle can be activated by direct stimulation of the muscle tissue, requiring a relatively high amplitude electrical stimulus.

Department of Veterans Affairs (VA)

The department of the federal government responsible for overseeing veteran services, including health care. The VA’s Rehabilitation Research and Development service sponsors a large portion of Functional Electrical Stimulation research.

Dermatomal stimulation

Stimulation of a dermatome, an area of the skin in which all the sensory nerve receptors belong to the same spinal cord level, to control spasticity.

Diaphragm

A dome-shaped muscle that separates the chest and abdominal cavities. Aids breathing by its upward and downward movements.

Diaphragm pacing

Electrical stimulation of the diaphragm to produce respiration. Stimulation may be applied at the phrenic nerve or at the diaphragm muscle.

Direct current (DC)

The continuous unidirectional flow of charged particles, the direction of which is determined by the polarity selected. May refer to a type of stimulation current. Sometimes called galvanic stimulation. See also Alternating Current.

Disability

A medically determined physical, mental, sensory or emotional impairment that interferes with major tasks of daily living.

Doffing

Taking an article off, as in removing a leg brace or wrist splint.

Donning

Putting an article on, as in putting on a surface electrode system.

Dorsal column stimulation

See Spinal cord stimulation.

Dynamic graciloplasty

An FES system that keeps the rectum closed. The system requires a surgical procedure that transfers a leg muscle (gracilis) to be a loop around the rectum. An electrode to that muscle and a stimulator are implanted.

E

Efferent

Conveying nerve impulses toward a muscle or other organ. See also Afferent.

Electrical muscle stimulation (EMS)

Use of electricity to activate muscles.

Electrical stimulation

A broad term which refers to the therapeutic or functional use of electrical current in the human body to produce a particular outcome.

Electrocutaneous stimulation

See Electrotactile stimulation.

Electrode

The conduction medium used to apply an electrical current to the body or to record an electrical signal coming from the body. A minimal electrode system consists of one anode and one cathode. Electrodes are manufactured from a variety of materials and in various styles. See also Cuff electrode, Epimysial electrode; Intramuscular electrode; Needle electrode; Nerve electrode; Surface electrode.

Electrode array

A type of electrode that has multiple electrical contacts in one compact unit for recording from or stimulating at multiple sites.

Electrode burn

A burn on the skin or in the body that results when current is applied to an electrode at an intensity that is higher than a safe level.

Electrode lead

The wire that attaches the electrode to the stimulator.

Electroejaculation

The technique used to induce ejaculation of sperm in the male by electrical excitation of the sensory organs, typically by stimulation inside the rectum.

Electromagnetic stimulation

See Magnetic stimulation.

Electromyogram (EMG)

The electrical activity recorded from a muscle. Can be used to study muscle contractions. Often used in biofeedback techniques.

Electrophysiology

The study of the physiologic effects of electrical activation of the nervous system.

Electrotactile stimulation

The use of electrical stimulation to activate the sensory nerves responsible for the sense of touch. May be used in sensory feedback or visual prosthesis applications. Also known as electrocutaneous stimulation.

Electrotherapy

The clinical practice of applying electricity to the body to achieve a therapeutic result. This would include FES applications such as muscle strengthening, wound healing, contracture prevention, and improving circulation.

EMG

See Electromyogram.

EMS

See Electrical muscle stimulation.

Energy

The capacity to do work or to perform vigorous activities.

Epimysial electrode

An electrode that is surgically fixed to the surface of the muscle.

Erection

See Penile erection.

Ergometry

The study of the work performed by muscles. See also Bicycle ergometry.

Ergotherapy

The use of physical activity and exercise in the treatment of disease.

Excitability

A measure of the ease with which a cell, nerve, or muscle can be excited.

Excitation

See Stimulation.

Exercise

See Muscle strengthening.

Experimental research

Any use of FES that is considered to be investigational by the FDA or other foreign authority.

Extension

A movement that increases the angle between two adjoining bones of the skeletal system. See also Flexion.

F

Facilitation.

Supplementation of a patient’s voluntary muscle response with various motor and sensory stimuli. See also Biofeedback.

Faradaic stimulation.

Describes a specific type of pulsed current generated by rotating a coiled wire in a magnetic field. Sometimes mistakenly used to refer to AC stimulation.

Fatigue

The loss of the ability of muscle tissues to respond to stimuli that normally would cause a muscular contraction. Occurs following strenuous physical activity.

FDA

See Food & Drug Administration.

Feasibility

Typically refers to a research study at a single institution involving 10 or fewer subjects.

Feedback

Information about what is taking place in response to a stimulus that is returned to the stimulus controller; e.g., force and position information. See also Control; Sensor.

FES

See Functional Electrical Stimulation.

Flexion

A movement which decreases the angle between two adjoining bones of the skeletal system. See also Extension.

Floor reaction orthosis

A rigid ankle foot orthosis developed in the 1960s which uses the ground reaction vector to provide stability for standing. See also Hybrid orthosis.

FNS

See Functional neuromuscular stimulation.

Food and Drug Administration

The federal agency responsible for regulating the safety and efficacy of medical devices sold in the U.S.

Foot-drop

An abnormal neuromuscular condition which is characterized by the inability to dorsi-flex or invert the foot due to peroneal nerve interruption, often resulting from stroke. May be corrected by orthoses or electrical stimulation of the peroneal nerve.

Force

Energy or “pressure” applied in such a way that it initiates motion or alters the size or shape of an object.

Frequency

The rate of occurrence of stimulus pulses.

Functional Electrical Stimulation (FES)

As defined by the FES Information Center: a rehabilitation technique where low-level electrical current is applied to an individual with a disability to enhance that person’s ability to function and live independently. Usually refers to applications which provide long term assistance or replacement of a missing or impaired body function. The term often has different meanings in different communities; if the definition is not clear, ask for clarification. See also Therapeutic electrical stimulation.

Functional evaluation.

A clinical evaluation of a person based on the completion of tasks, often including the activities of daily living.

Functional neuromuscular stimulation (FNS)

The application of electrical stimulation to the neuromuscular system for the purpose of completing functional tasks. Sometimes used interchangeably with FES. Typically refers to the use of electrical stimulation to provide long term assistance or replacement of an impaired neuromuscular function.

Funding

Financial support for a research project.

G

Gait.

The act of walking or ambulation. Can be assisted by electrical stimulation and/or orthoses. See also Hybrid orthosis.

Galvanic stimulation

See Direct current.

Ground reaction orthosis

See Floor reaction orthosis.

Guillain-Barre syndrome

A disease of the peripheral nervous system which may cause pain and weakness in the extremities as well as paralysis. Also known as an idiopathic polyneuritis. In general, FES is not a treatment option.

H

Hand grasp stimulation.

Stimulation of upper extremity musculature to induce functional movement of the hand.

Handicap

The disadvantage which occurs when the design of the environment poses obstacles or barriers to people with disabilities.

Head injury

A traumatic injury to the head that can lead to brain cell damage resulting in brain dysfunction.

Hemiplegia

Paralysis on one side of the body, often as a result of stroke or cerebrovascular accident (CVA).

HGO

See Hip guidance orthosis.

High voltage electrical stimulation (HVES)

A type of electrical stimulation which uses electrical stimuli with very short, high voltage pulses. Sometimes known as high voltage pulsed current (HVPC).

High voltage pulsed current (HVPC)

See High voltage electrical stimulation.

Hip guidance orthosis (HGO)

A system that incorporates a rigid body brace, a hip joint with limited movement, stable knees and ankles, and a shoe plate. Can be used with crutches to provide reciprocal walking. Also known as ParaWalker. See also Hybrid orthosis.

HKAFO

Used to describe a hip-knee-ankle-foot orthosis which can provide gait assistance in total paraplegia. Sometimes used in conjunction with electrical stimulation. See also Hybrid orthosis.

HVES

See High voltage electrical stimulation.

HVPC

High voltage pulsed current. See High voltage electrical stimulation.

Hybrid orthosis

An FES system which uses an orthosis (brace) in conjunction with electrical stimulation to provide function.

Hypertrophy

Increase in the size of a muscle. See also Atrophy.

I

Implant

A medical device which is surgically wholly implanted in the body.

Implantable stimulator

Miniaturized stimulation system surgically placed into the body. If the stimulation system requires a transmitter and receiver, the receiver will be implanted as well.

Impulse

A single electrical signal of short duration. See also Pulse.

Incomplete spinal lesion.

An injury to the spinal cord which leaves some pathways for transmission of nerve signals intact. Some muscle control and sensation may remain. See also Complete spinal lesion.

Incontinence

The inability to control urination or defecation due to lack of sphincter control. Electrical stimulation of the sphincter muscle may return some degree of control.

Independent living

Controlling and directing your own life by making decisions and taking responsibility for your actions.

Informed consent

Prior to participating in an investigational FES program, the subject is presented with information about potential risks and benefits. To acknowledge that the subject understands the information, he or she signs an informed consent document.

Innervation

The distribution or supply of nerve fibers or nerve impulses to a part of the body. An innervated muscle can be readily activated with low amplitude electrical stimulation. See also Denervation.

Intramuscular electrode

An indwelling electrode placed into a muscle using a hypodermic needle, either through closed skin or an open incision.

Ischemia

A local decrease in oxygen flow to a tissue due to obstruction of blood flow.

Ischemic sore

See Decubitus ulcer.

J

JCAHO

Joint Commission on the Accreditation of Healthcare Organizations.

Joint contracture

An abnormal condition of a joint characterized by flexion and fixation. These are caused by atrophy and shortening of muscle fibers or by the loss of normal elasticity of the skin due to scarring. Electrical stimulation can be used to overcome the restrictions of contractures by cyclically stretching the muscle group antagonistic to the contracture.

K

KAFO

Refers to a knee-ankle-foot orthosis used to stabilize and control the movement of the lower extremity joints.

L

Laboratory-based equipment

Equipment that is located and used exclusively in a laboratory setting.

Lead

See Electrode lead.

Lesion

A discontinuity in the central nervous system. See also Complete spinal lesion; Incomplete spinal lesion; Lower motor neuron; Upper motor neuron.

Long leg brace

An orthotic device that allows paraplegics to walk on level surfaces by locking the ankles and knees.

Lower extremity

The hip, leg and foot.

Lower motor neuron

Cells located in the spinal cord that have extending nerve fibers which leave the spinal cord and then innervate skeletal muscles. If the lower motor neurons for a particular muscle are not intact due to injury or disease, electrical stimulation of the nerve and muscle will be impossible. Lower motor neuron damage may be present in spinal cord injury, spina bifida, and ALS. See also Denervation; Peripheral nervous system.

Lymph

Clear liquid that flows in lymphatic vessels throughout the body. Contains protein, some white blood cells, and few red blood cells.

M

Magnetic stimulation

Stimulation of nerves induced by magnetic fields. Used with brain stimulation and implantable or surface stimulation techniques.

Micturition

Elimination of urine from the bladder; urination.

Motor training

See Facilitation.

MS

See Multiple sclerosis.

Multicenter clinical trials

A stage of FES development characterized by well-controlled studies in two or more clinics involving large numbers of human subjects.

Multiple sclerosis (MS)

A progressive CNS disease characterized by destruction of the myelin sheath that insulates nerve cell axons, causing interruption of neural signals. There is some indication that FES may be used to improve function in individuals with MS.

Muscle conditioning

The process of converting a muscle fiber type from fast-twitch fibers to slow- twitch fibers by electrical stimulation to decrease the likelihood of muscle fatigue.

Muscle contraction

See Contraction.

Muscle exercise

See Muscle strengthening.

Muscle reeducation

See Facilitation.

Muscle strengthening

The use of electrical stimulation to cause repeated contractions of muscles which have become weak and atrophied. Causes a change in muscle fiber type which results in a muscle less likely to fatigue. May increase muscle bulk, thereby changing the appearance of the extremities. Portable stimulators with surface electrodes are typically used in physical therapy clinics for this purpose. See also Muscle conditioning; Atrophy; Hypertrophy.

Musculoskeletal

Related to the function of the bones, muscles, and their interactions.

N

National Center for Medical Rehabilitation Research (NCMRR)

A center of the National Institutes of Health devoted to improving the quality of life of individuals with medical disabilities.

National Institute of Neurological Disorders and Stroke (NINDS)

One of the National Institutes of Health devoted to the study of neurological diseases and disorders.

National Institute on Disability and Rehabilitation Research (NIDRR)

A federal agency of the Department of Education, Office of Special Education and Rehabilitative Services to support the development of devices and programs which improve the ability of individuals with disabilities to live independently.

National Institutes of Health (NIH)

A group of agencies commissioned by the Department of Health and Human Services to oversee research into health-related problems. Includes the NINDS and NCMRR which sponsor a large portion of FES research.

NCMRR

See National Center for Medical Rehabilitation Research.

Needle electrode

A surgical-grade needle used to record or deliver electrical impulses.

Nerve

One or more bundles of fibers which carry electrical impulses. The fibers connect the brain and spinal cord with other parts of the body. See also Axon, Neuron.

Nerve electrode

An electrode surgically placed in, near or around the nerve. Also known as nerve cuff, intraneural, or epineural electrodes. See also Cuff electrode.

Neural prosthesis

A device which acts to replace or improve the function of an impaired nervous system.

Neural regeneration

The use of electrical stimulation to enhance the regeneration of nerve fibers that have been severed due to accident or disease.

Neurological level

In spinal injury, refers to the most caudal segment of the spinal cord with normal sensory and motor function on both sides of the body.

Neuromodulation

A method of reducing spasticity and improving motor control by stimulating sensory nerves.

Neuromuscular

Related to the function of nerves and muscles.

Neuromuscular electrical stimulation (NMES)

Electrical stimulation of nerves to produce muscle contraction.

Neuron

The basic nerve cell of the nervous system. See also Axon; Nerve.

Neurophysiology

The study of the processes and functions of the nervous system.

Neuroprosthesis

See Neural prosthesis.

NIDRR

See National Institute on Disability and Rehabilitation Research.

NIH

See National Institutes of Health.

NINDS

See National Institute of Neurological Disorders and Stroke.

NMES

See Neuromuscular electrical stimulation.

O

Open-loop control

See Control.

Orthosis

A device used to support or brace a weak or disabled joint or muscle.

Osteoarthritis

Chronic disease involving the joints. Involves degeneration of cartilage, overgrowth of bone, and impaired function. Almost always occurs with aging.

Osteoporosis

A disorder characterized by increased fragility of the bones, often occurring in immobilized individuals.

P

Parameters

In FES, a set of properties whose values determine the characteristics of the stimulation. Usually includes level of current or voltage, duration of a stimulus pulse, and frequency of stimulation.

Paraplegia

Paralysis of the legs and lower parts of the body due to an injury to the spine at the thoracic, or chest, level.

Patient selection

The criteria applied to assess the appropriateness of a candidate for a particular electrical stimulation program. Criteria usually include medical, physiological, rehabilitative psychological, and social factors.

Pelvic floor stimulation

Electrical stimulation applied to the pelvic muscles that support the bladder, bowel, and reproductive organs.

Penile erection

Sometimes results from sacral nerve stimulation for bowel or bladder emptying. In one study, the resulting erection was strong enough for intercourse in half of the population studied.

Percutaneous

Through the skin.

Percutaneous electrode.

An electrode inserted through the skin, usually using a hypodermic needle.

Peripheral nervous system

The motor and sensory nerves outside the brain and spinal cord. Diseases of the peripheral nervous system include polio, muscular dystrophy, Guillain-Barre Syndrome, and hereditary nerve diseases such as Charcot Marie Tooth Syndrome. In general, FES is not a treatment option when the peripheral nervous system is damaged. See also Denervation.

Peripheral neuropathy

A disorder of nerves that lie outside the brain and spinal cord. Can be caused by a variety of afflictions including diabetes, alcoholism, kidney failure, and exposure to environmental substances. In general, FES is not a treatment option. See also Denervation.

Portable stimulator

A stimulator that is compact, lightweight and powered in such a way that it can easily travel with an individual.

Postural stabilization

Electrical stimulation of the spinal and other muscles to assist with balance.

Power supply

The method for powering a stimulator. Examples are AC (line) powered, battery (rechargeable or replaceable) powered, and radio frequency (RF) powered (typically used with implants).

Pressure sore

See Decubitus ulcer.

Pressure sore relief

The periodic use of surface electrical stimulation to increase circulation and shift the load on weight-bearing tissues in an area prone to pressure sores.

Proprioception.

Awareness of posture, movement, changes in balance, and knowledge of position, weight and resistance of objects in relation to the body.

Prosthesis.

A device used as a substitute for a missing or dysfunctional part of the body.

Pulse

A brief injection of electrical current, typically lasting only microseconds. Most stimulation systems produce many pulses in a sequence to cause nerve activation. See also Impulse.

Q

Quadriplegia

Paralysis of the arms, legs and trunk that occurs with an injury to the spine in the cervical (neck) area. Also known as tetraplegia.

R

Range of motion

The extent to which a joint can move in all possible directions. A type of exercise, active or passive, used to assess the condition of the muscles and joints by body movement. Electrical stimulation can be used to move limbs through their range of motion.

Reciprocal walking

A gait pattern where one leg is sequentially placed in front of the other.

Reciprocating gait orthosis (RGO)

A hip-knee-ankle-foot orthosis with coupling such that hip extension in one leg causes hip flexion in the other, causing reciprocal walking.

Recruitment

The relationship between the electrical charge injected into a stimulating electrode and the resulting force generated by the activated muscle. In general, force increases as the charge, or intensity, increases. See also Threshold.

Rectum

Lower part of the bowel, just inside the anus.

Reflex.

An action that occurs subconsciously when certain signals that start in a nerve ending travel to the spinal cord or brain. An example is the automatic kicking of the lower leg when the knee is tapped with a rubber hammer.

Regulatory approval

Treatment and any associated medical devices that have received approval from the Food and Drug Administration (FDA) in the United States, or a comparable regulatory agency in other countries.

Rehabilitation engineering

The systematic application of technologies or scientific principles to meet the needs of, and address barriers confronted by, individuals with disabilities. This includes areas such as education, rehabilitation, employment, transportation, communication, independent living and recreation.

Rehabilitation Technology

Any technology used to restore or improve function in an individual after a disabling disease or injury. Also known as assistive technology.

Respiratory assist

A system that enhances the act of breathing. Examples are an iron lung or a phrenic nerve pacer.

Restoration

The return of function by direct or indirect means after the loss of function.

RGO

See Reciprocating gait orthosis.

Rhizotomy

Cutting of a spinal nerve root.

S

SCI

See Spinal cord injury.

SCS

See Spinal cord stimulation.

Sensation

A feeling, impression, or awareness of a bodily state or condition that results from stimulation of a sensory nerve fiber.

Sensor

A device that provides electronic information about a situation, such as force or position information. Also known as transducer.

Sensory electrode

An electrode or electrode array with the purpose of providing substitute sensory information or system information to the user.

Sensory feedback

Providing sensory information to help describe what is happening (usually to the FES system) during a certain situation; e.g., tactile stimulation to represent grasp force.

Sensory substitution

The use of one human sense to receive information normally received by another sense. In FES, typically electrotactile information is substituted for an impaired sense.

Sexual function

See Electroejaculation; Penile erection.

Skeletal muscle

Muscle tissue consisting of bundles of parallel fibers. Normally contraction is under voluntary control, as in the muscles that control upper and lower extremity movement. Also known as striated muscle. See also Smooth muscle.

Smooth muscle.

Muscle tissue composed of elongated, spindle-shaped cells not under voluntary control, as in the muscles of the stomach and intestines. See also Skeletal muscle.

Spasm

Involuntary, sudden movement or muscle contraction. May be sustained (tonic) or alternately contracting and relaxing (clonic). When strong and painful, spasms are called cramps.

Spasticity

A condition caused by involuntary contraction of muscles due to a spinal cord lesion or other central nervous system disorder. Electrical stimulation may, in some cases, be used to counteract the involuntary contractions, thereby reducing spasticity.

Spinal cord injury (SCI)

Injury to the neural structures of the spinal column, often due to traumatic accident, resulting in upper and lower motor neuron lesions. Typically leads to paralysis and loss of sensation in parts of the body controlled through the spinal cord below the level where the injury occurred. Some central nervous system diseases have similar effects.

Spinal cord stimulation (SCS)

Stimulation of the spinal neural axis to treat pain and various disorders of the motor system. Typically involves insertion of electrodes into the epidural space with subcutaneous placement of a stimulator/receiver. Also known as dorsal column stimulation. See also Implantable stimulator.

Stimulation

Application of stimuli to activate sensory and/or motor nerves.

Stimulator

A device used to apply an electrical or magnetic stimulus through an electrode to a nerve or muscle. May have single or multiple channels. See also Channel; Implantable stimulator; laboratory-based equipment; Portable stimulator.

Stimulus

A current or voltage pulse or pulse train, characterized by amplitude, shape, duration, and frequency, that excites nerves and muscles when applied to the body. See also Parameters.

Stimulus intensity

The amount of stimulation applied to the body, usually a combination of frequency, pulse duration, and amplitude. See also Parameters.

Strengthening

See Muscle conditioning.

Stroke

Sudden paralysis caused by interruption (transient ischemic attack - TIA) or blocking (cerebral infarction) of circulation to a part of the brain or by sudden bleeding into the substance of the brain (intracerebral hemorrhage). Also known as CVA.

Subcutaneous

Under the skin.

Surface electrode

An electrode placed on the surface of the skin over a muscle, peripheral nerve, or skin afferents (sensory receptors that carry impulses towards the CNS) to be stimulated. The electrode is held to the skin by adhesive, tape, bandaging or tight-fitting garments. Surface electrodes are used with electrode gel or paste to enhance electrical conductivity between the skin and the electrode.

Swing-through walking

A gait pattern which results when the trunk and legs follow an initial forward movement by the arms using a walker, crutches, or other stabilizing device. See also Reciprocal walking.

T

Tactile

See Electrotactile.

Technology transfer

The process whereby a research technology is transformed into a commercially available product.

Tendon

A fibrous band of tissue which attaches muscle to bone.

Tendon transfer

Surgical removal and subsequent replacement of the insertion point of a tendon to provide improved function during movement. Typically used in the hand for rehabilitation of people with quadriplegia.

Tendonitis

Inflammation of a tendon.

TENS

See Transcutaneous electrical nerve stimulation.

Tetraplegia

See Quadriplegia.

Therapeutic

Any treatment of a disorder which is deemed beneficial, but not necessary to sustain life. May have short- or long-term effects.

Therapeutic electrical stimulation.

A general term which usually refers to electrical stimulation applied to the body to provide healing or natural restoration of a missing or impaired body function.

Threshold

The level at which any further increases in stimulus intensity will cause activation of a nerve or muscle.

TIA

Transient ischemic attack. See Stroke.

Training

See Muscle conditioning.

Transcutaneous electrode

See Surface electrode.

Transcutaneous electrical nerve stimulation (TENS)

Method of electrically activating nerves by the use of surface stimulation, typically for the purpose of relieving pain.

Transducer

See Sensor.

Tremor

Shaking that occurs continuously or whenever a voluntary movement is made.

U

Unlabelled use

Use of a device or drug that is approved for one purpose for a different purpose. Doctors may do this for particular patients, but very often the unlabelled use will not be covered by insurance. An example is use of a spinal cord stimulator (approved for treating pain) for improving bladder control.

Upper extremity

The shoulder, arm and hand.

Upper motor neuron

Cells which extend from the brain to the spinal column. Diseases of the upper motor neuron are characterized by increased muscle tone and spasticity, diminished superficial reflexes, and no local twitching of muscle groups. See Lower motor neuron.

V

VA

See Department of Veterans Affairs.

W

Walking

See Gait.

Wound healing

A stimulation technique that may increase the speed at which a wound heals by inducing an electrical field across the surface of a wound.