Treatments & Therapies

Electrostimulation – treatment, effects and risks


During electrical stimulation , a motor nerve is contacted using an applied voltage. Through this contact, an action potential reaches the muscle, which causes it to contract. Therapeutic electrostimulation is mainly used in peripheral paralysis and is intended to prevent muscle atrophy .

What is electrostimulation?

Electrostimulation is therapeutic stimulation by an applied voltage source. Electrostimulative procedures are mainly used in nerve failures. When peripheral nerves of the body fail, the muscle cells in the supply area of ​​the paralyzed nerve often deteriorate, especially in the arms and legs.

This degradation is related to the fact that the muscles do not receive electrical signals through the nerve. The signals from the nerve can be replaced by electrostimulating therapies. In such a therapy session, attached electrodes emit small current surges into the tissue and thus control the affected nerve. Through the control, stimulating signals reach the threatened muscle, which result in a muscle contraction. Ideally, the contractions brought about in this way will not result in atrophy of the paralyzed muscle.

Human muscles respond differently to different types of current modulation. In most cases, voltage curves with an exponential curve are best suited for electrostimulation. In addition to this area of ​​application, the therapeutic measures are also used on men with anejaculation to stimulate ejaculation .

Function, effect & goals

Functional electrical stimulation corresponds to the electrical stimulation of a specific muscle or muscle group. The process can be direct or indirect. The electrical signal stimulates motor nerves, which trigger muscle contraction.

An implanted functional electrical stimulation takes place, for example, with the cardiac pacemaker . Depending on the damage, the regular stimulating signal from the pacemaker excites the heart muscle in the right atrium or in the region of the right ventricle. The respiratory pacemaker is also based on implanted functional electrical stimulation and mainly stimulates the phrenic nerve . Other uses of the implanted form are the intestinal pacemaker and the bladder pacemaker, which stimulate the muscles involved in elimination to contract. Another area of ​​application for electrostimulation is the cochlear implant of the hearing-impaired.

The implant electrically stimulates the auditory nerve , enabling hearing even after severe hearing loss . This type of electrical stimulation excites different regions of the basilar membrane and thus stimulates the ganglion cells in the auditory organ. Every nerve stimulation requires an applied field strength with a certain gradient strength, which can trigger an action potential in the nerve contacted. This potential travels down the motor nerve to the motor endplate of a muscle. The stimulation again triggers an action potential in the muscle and thus causes the activated muscle to contract. However, muscle cells can also be stimulated directly.

Electrical stimuli for direct muscle stimulation are much larger and last much longer than those for stimulating certain nerves. For both nerve and muscle electrostimulation, surface electrodes are placed on the patient’s skin . Normally, these measures take place within a rehabilitation facility. By changing the stimulation frequency, the individual areas of the muscle fibers are stimulated to different degrees during electrostimulation. Frequencies up to 200 Hz primarily activate the fast muscle fibers. Those up to 10 Hz improve the endurance of the slow muscle fibers.

Direct muscle electrostimulation corresponds to training and can therefore also take place on top athletes, for example. The now effective application of direct muscle electrostimulation relates to denervated muscles after permanent peripheral paralysis and uses impulses of up to 300 MS width. The intensities of the stimulation range up to 250 mA.

Risks, side effects & dangers

As a therapeutic method, electrostimulation is associated with a number of risks and side effects. The human body is sensitive to electrical currents. For this reason, even small voltages below 40 volts can cause negative effects if they are applied under unfavorable conditions.

These unfavorable conditions include, for example, highly conductive sweat . In individual cases, electrostimulation causes injuries such as minor burns or functional impairments of peripheral nerves.

Since improper use can also impair the conduction of the heart muscle cells, life-threatening cardiac arrhythmias can occur in extreme cases . In the context of direct muscle stimulation, pain can also occur as a side effect of electrical stimulation . Some patients only experience low-frequency stimulation current as an unpleasant pulling.

Others complain of extremely painful sensations. In patients without the appropriate innervation, these side effects take care of themselves. All other patients are now usually treated with medium-frequency current for direct muscle stimulation, which corresponds to frequencies above 1000 Hz and is not sensitive to stress.

The electrical resistance to electrical stimuli is frequency-dependent in inverse proportion. Experience has shown that frequencies of around 2,000 Hz in modulated currents are particularly effective. Modulated medium frequency is already used in a standardized way by certain therapy devices and training systems. Skin rashes can appear in the area of ​​the activated electrodes both during the electrostimulation of nerves and the stimulation of muscles.

However , patients with allergies to certain adhesives should make these allergies known to their therapist. In absolutely exceptional cases, sensory disturbances remain on the skin after electrostimulation , which lead to permanent discomfort . Such abnormal sensations can correspond, for example, to a persistent feeling of numbness or a disturbance in the perception of warm and cold. Despite the possible risks, most patients tolerate electrostimulation well. Some even find the impulses relaxing.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.