Introduction

Electricity is everywhere. Did you know that the human body has electrical properties? 

The skin provides more than 99% of the body's resistance to electric current flow.¹ This discovery highlights a fundamental truth: our bodies are inherently interwoven with electrical phenomena, and this interplay has far-reaching ramifications for our health. Electrical stimulation has emerged as a promising pathway for tissue repair and regeneration in the field of regenerative medicine and therapeutic interventions.

This novel method uses the body's natural electrical qualities to expedite healing processes, providing a non-invasive and frequently highly effective method of treating a wide range of tissue injuries and disorders. 

The possibility of electrical stimulation in tissue recovery has sparked a great deal of curiosity among researchers and physicians alike, from bone fractures to nerve damage and skin wounds. In this investigation, we examine the underlying mechanisms, many uses, and an expanding body of research that highlights the significant influence of electrical stimulation on the body's natural capacity for healing and rejuvenation.

What is electrical stimulation?

Electrical stimulation, or E-stim is a type of technique that uses electrical impulses to cause muscle contractions. On the skin, electrodes are applied over a predetermined area and controlled by a device. The muscle is then delivered electrical current from the device through the electrodes and contracts as a result. 

History

Electrical stimulation has been used for regenerative purposes for a very long time. It was created thousands of years ago, in BC. Ancient Egyptians, followed by the Greeks and Romans, were the first to recognise that electrical fish may provide electric shocks to relieve pain. 

Let's jump ahead to the eighteenth century. German physician Altus Kratzstein published a book on the therapeutic use of electricity in 1745. He believed that electrical currents could aid in muscular control. Luigi Galvani, an Italian physician and scientist, conducted animal tests at the same period. He made a frog's legs move by applying electricity to its spine. 

The "Faradization technique" first surfaced in 1831 and was used in the 19th century. It was a pioneering type of electrical therapy that was effective in healing muscular issues. Beginning around 1840, a physicist and chemist by the name of Michael Faraday who was particularly interested in investigating electricity and magnets contributed to the increased use of this therapy in hospitals in London. 

Later, in the 1860s, in London, a business known as The Medical Battery Company developed a device known as the Electropathic Battery Belt, which was somewhat comparable to a contemporary electrical device. 

The number of electrical muscle stimulation devices increased as we entered the 20th century. However, many of them were large, awkward to manoeuvre, and they delivered very unpleasant electrical shocks. From the 1920s through the mid-1960s, doctors began employing these early EMS devices to treat a variety of health problems.²

How does electrical stimulation work? 

E-stim therapy, also known as electrical stimulation therapy, targets particular muscles to cause contractions by providing controlled electrical signals via your neural system. The normal action potential produced by your central nervous system is what this technique seeks to imitate.

Your therapist applies electrode pads to your skin during the E-stim procedure. These pads are attached to a machine that generates electrical impulses, causing your skeletal muscles to contract. The device has a dial that your therapist can turn to change the settings.

Physical therapy like this usually causes only small muscular spasms that are barely perceptible while being performed. In order to produce the intended therapeutic results, e-stim therapy includes the continuous administration of electric impulses, resulting in recurrent muscle contractions and relaxations.

Types of electrical stimulation

1. Transcutaneous Electrical Neuromuscular Stimulation (TENS):  

Transcutaneous electrical nerve stimulation (TENS) is a way to help with pain by using a gentle electric current. It resembles a little battery-operated gadget that attaches to electrodes, which are sticky pads. The pads are applied to your skin. You will experience tingling when you turn on the device since it provides very small electric signals to the painful spot. By weakening the pain impulses that reach your brain and spinal cord, these signals may help you feel better and relax your muscles. They could also instruct your body to produce endorphins, which are organic painkillers. They are typically used for sports injuries, knee discomfort, menstrual pain, and arthritis. They are occasionally employed as a childbirth pain management technique.⁶

2. Neuromuscular Electrical Stimulation (NMES):

Neuromuscular Electrical Stimulation is a common modality used to retrain muscles and improve muscular strength after injury or surgery, particularly for the quadriceps muscle. 

NMES may target fast motor units more favourably, which is advantageous for fast-twitch muscle fibres that frequently become exhausted following injury and surgery. Electrical stimulation that targets rapid motor units has a trade-off in that it causes early muscle exhaustion, more patient discomfort, and a higher risk of treatment-related muscle injury.³

3. Interferential Current (IFC):

Interferential therapy is the application of low-frequency electrical current to stimulate nerve activity. This is intended to provide pain relief and improve blood flow to the bodily part that has been wounded. Additionally, this can help your body heal more quickly by reducing swelling and inflammation and activating natural hormones. This is not advised for those who are expecting, suffer from cancer or epilepsy, have recently recovered from an infection, or have heart or circulatory issues.

4. High-Voltage Galvanic Current (HVGC):

An electrical signal is conducted in the wound using a secure electrical current and specialised silver dressing. Low-frequency, high-voltage electricity is used in this. HVGC stimulation is used by physical therapists to reach deep tissues. This E-stim aids in ulcer healing, ulcer pain relief, improved peripheral circulation, and increased joint mobility.

5. Functional Electrical Stimulation (FES):

Small electric charges are applied to a muscle that has become paralysed or weak as a result of damage to the brain or spinal cord during this sort of treatment. It is primarily used as a treatment for foot drop in multiple sclerosis (MS), a condition where abnormalities in the neural pathways between the legs and brain prevent the front of the foot from being elevated to the proper angle when walking. According to research, FES therapy results in a more natural walking pattern, allowing patients to move faster, further, and with less effort.

Limitations and risks of e-stim:

Although largely regarded as useful and safe, electrical stimulation can have certain inherent hazards. Especially when considering or receiving electrical stimulation therapy, it's critical to be aware of these risks:

1. Skin Irritation: Using electrodes incorrectly or for an extended period might cause skin rashes, redness, or irritation at the electrode implantation locations. This risk can be reduced with good skincare and routine electrode rotation.⁴

2. Discomfort or Pain: If the intensity is too high or if the person has sensitive skin, they may feel discomfort or even pain during electrical stimulation sessions. The feeling might be anything from a slight tingling to uncomfortable.⁵

3. Muscle Soreness: Similar to the soreness one might feel after a rigorous workout, intense or sustained electrical stimulation can cause muscle soreness. Usually, this is a brief side effect.⁶

4. Electrode Burns: On occasion, a malfunctioning device or electrodes that are too hot might result in electrode burns. Burns can be avoided by using high-quality electrodes and keeping an eye on the skin's health while receiving therapy.⁷

5. Spasms or Twitching: Although it can be uncomfortable, some people may feel muscle spasms or twitching during or after electrical stimulation. This risk can be decreased with appropriate stimulation parameter adjustment.

6. Interference with Medical Devices: Electrical stimulation tools may cause issues with defibrillators or pacemakers, among other medical tools. If you have any implanted medical equipment, you must speak with a healthcare provider before receiving electrical stimulation therapy.⁸

7. Tissue Damage: If the electrodes are positioned inappropriately or the intensity is too high, excessive or improper usage of electrical stimulation may result in tissue damage.⁹

8. Overstimulation of the Nerve or Muscle: Overstimulation of the nerve or muscle can cause weariness, pain, or injury. Use the proper stimulation parameters, and when necessary, get advice from a healthcare expert.

To reduce these hazards and guarantee the therapy's efficiency and safety, it's essential to receive electrical stimulation therapy under the supervision of a licenced healthcare provider who can evaluate your unique needs, set appropriate parameters, and keep track of your development.

Summary

Electrical stimulation therapy, or E-stim, harnesses the body's natural electrical properties to accelerate healing. In a world where electricity is ubiquitous, the revelation that our bodies possess inherent electrical characteristics underscores the profound connection between electricity and well-being. This innovative approach, dating back to ancient cultures and refined over centuries, has emerged as a promising tool for tissue repair and regeneration. By delivering controlled electrical signals to target muscles, E-stim induces contractions, aiding in pain relief, muscle retraining, and more. However, it's essential to be aware of potential risks, including skin irritation and discomfort, and to undergo E-stim therapy under professional guidance to ensure its safe and effective application.