Whether you’re recovering from an injury or stroke or dealing with the pain of fibromyalgia or another condition, you may benefit from a physical therapy procedure called electrical stimulation, or e-stim.
E-stim sends mild electrical pulses through the skin to help stimulate injured muscles or manipulate nerves to reduce pain.
E-stim may not be appropriate for everyone, but for many people this painless procedure is accelerating recovery and providing relief from painful or uncomfortable symptoms.
E-stim uses electrical pulses to mimic the action of signals coming from neurons (cells in your nervous system). These mild electrical currents target either muscles or nerves.
E-stim therapy for muscle recovery sends signals to targeted muscles to make them contract. (Flexing your biceps is a form of muscle contraction.) By causing repeated muscle contractions, blood flow improves, helping repair injured muscles.
Those muscles also improve their strength through repeated cycles of contraction and relaxation. E-stim can also “train” muscles to respond to the body’s natural signals to contract. This is an especially helpful benefit for stroke survivors who must essentially relearn basic motor functions.
The type of e-stim that focuses on pain relief sends signals on a different wavelength so they reach the nerves, rather than the muscles. Electrical stimulation can block pain receptors from being sent from nerves to the brain.
The two main types of e-stim are transcutaneous electrical nerve stimulation (TENS) and electrical muscle stimulation (EMS).
TENS
TENS may be used for chronic (long-term) pain as well as for acute (short-term) pain. Electrodes are placed on the skin near the source of the pain. Signals are sent through nerve fibers to block or at least reduce the pain signals traveling to the brain.
EMS
EMS uses a slightly stronger current than TENS to get muscles to contract. The unit’s electrodes (also placed on the skin near the affected muscles) cause rhythmic contractions. This can improve muscle strength if the user attempts to contract the muscle simultaneously.
Other e-stim types
In addition to EMS and TENS, your doctor or physical therapist may recommend other e-stim treatments.
other types of e-stimOne of the following similar e-stim treatments may help you, depending on your condition:
- Electrical stimulation for tissue repair (ESTR) helps reduce swelling, increase circulation, and speed up wound healing.
- Interferential current (IFC) stimulates nerves to reduce pain.
- Neuromuscular electrical stimulation (NMES) stimulates the nerves in muscles to restore function and strength, prevent muscle atrophy, and reduce muscle spasms.
- Functional electrical stimulation (FES) involves a unit implanted in the body to provide long-term muscle stimulation aimed at preserving function and motor skills.
- Spinal cord stimulation (SCS) uses an implantable device to relieve pain.
- Iontophoresis helps deliver ionically charged medication to tissue to help speed up healing.
You may have seen TV and online advertisements for home e-stim systems. If you’re interested in one of these products, talk with your doctor or a physical therapist. Be sure to get proper instruction on its use before trying it out.
As part of a physical therapy program, you may be provided a battery-powered unit to use at home. Make sure the unit’s settings are correct before using it on your own.
How does e-stim work?
E-stim uses small electrodes placed on the skin. The electrodes are small, sticky pads that should come off with little discomfort at the end of the session.
Several electrodes are placed around the area receiving treatment. Wires from the e-stim device are attached to the pads.
Steady streams of electrical pulses are delivered through the wires from the e-stim unit. The unit may be small enough to fit in your hand or larger, like a landline phone and answering machine.
For muscular stimulation, the pulses will reach the muscles, signaling them to contract.
Pulses aimed at the nervous system block the transmission of pain signals from reaching the spinal cord and brain. The pulses also stimulate the body to produce more natural pain-relieving chemicals called endorphins.
What to expect during e-stim
- Electrodes are placed around the site receiving therapy.
- The electrical current will begin on a low setting and increased gradually.
- You’ll get a tingly, “pins and needles” feeling at the site.
- Depending on the type of e-stim, you may feel a muscle twitch or contract repeatedly.
- Each e-stim therapy session may last 5 to 15 minutes, depending on the condition being treated.
When e-stim is part of an overall physical therapy program, your insurance may cover it like other physical therapy treatments.
Check with your insurance provider first, however. The nature of your condition will often determine coverage. For example, an insurance provider may cover e-stim for scoliosis in serious cases, but not if the curvature is less than 20 degrees.
Home TENS or EMS systems can start at $20 for simple, starter units. Higher-end systems that are more durable and offer more features can cost several hundred dollars.
What does it treat?
E-stim may be appropriate for the following conditions:
- back pain
- cancer-related pain
- dysphagia (trouble swallowing)
- fibromyalgia
- joint pain
- arthritis
- muscle conditioning (mostly for athletes, such as long-distance runners)
- muscle injury from trauma or disease
- nerve inflammation
- poor muscle strength
- urinary incontinence
- spinal cord injury
- stroke
- surgery recovery
Researchers are also working on ways to use e-stim to help people with advanced multiple sclerosis walk again.
Risks of e-stim
The most common risk of e-stim is skin irritation where the electrodes are placed.
However, there’s a much more serious risk to heart health. For people with a pacemaker or other implantable heart device, e-stim may be dangerous and isn’t recommended.
E-stim is also not recommended for those who are pregnant. But in some supervised circumstances, e-stim has been used to help relieve labor pains.
What’s the outlook for people who use e-stim?
E-stim targeting the nerves for pain relief can be effective in treating a range of conditions causing nerve and musculoskeletal pain as well as pain that doesn’t respond to traditional treatments, according to 2019 research.
However, the researchers note e-stim isn’t always a first-line treatment. Rather, it’s part of a broader set of options available to physical therapists.
Depending on your condition, you could start to feel better after one e-stim session. You may need multiple sessions, depending on the severity of your condition and symptoms.
In a small 2019 study, researchers found that 36 NMES sessions over a 16-week period improved muscle function in people with rheumatoid arthritis.
E-stim is still considered an alternative therapy. There are some health experts who are skeptical of its long-term effectiveness.
There’s also some disagreement about which conditions are best suited for e-stim treatment.
Generally speaking, e-stim is most effective at working weakened or atrophied muscles and healing muscles after an injury or surgery.
As a pain reliever, e-stim (especially TENS therapy) can be effective in treating many conditions, though typically as part of a broader pain-management program.
Are there alternatives to e-stim?
While e-stim can be an effective tool in physical therapy and rehabilitation, it’s just one of many strategies employed by physical therapists, sports medicine physicians, and orthopedists.
Other forms of therapy include:
- muscle-strengthening exercises using weights, resistance bands, machines, and a person’s own body weight
- massage
- range-of-motion exercises
- stretching and flexibility exercises
- ice and heat treatments
The takeaway
E-stim treatments have become standard parts of physical therapy for many conditions.
When used as part of injury or surgery recovery, e-stim should be used as a prescribed, supervised treatment, though home use may be appropriate in many cases.
Just be sure to tell your healthcare provider if you have a heart condition or are pregnant.
Sharing your medical history and a list of medications and supplements you take is always a smart and safe approach, too.
If you’re interested in e-stim as a tool for muscle conditioning or pain relief, talk with your doctor about your options and how to proceed safely.