Can a TENS machine make sciatica worse?

A transcutaneous electrical nerve stimulation (TENS) machine is a device that some people with sciatica use to try to manage their pain. TENS machines work by sending low-voltage electrical currents through electrodes placed on the skin. The currents stimulate nerves in the treatment area, which may reduce the sensation of pain.

Some research suggests that TENS therapy may provide short-term relief for sciatica pain. However, there are also potential risks and downsides to using a TENS unit. One concern is that improper TENS use could potentially make sciatica worse in some cases.

What is sciatica?

Sciatica refers to pain that radiates along the path of the sciatic nerve, which branches from the lower back through the hips and buttocks and down each leg. The pain generally results from irritation or compression of the sciatic nerve roots in the lower spine.

Common causes of sciatica include:

  • Herniated (slipped) disc in the lower back
  • Degenerative disc disease
  • Spinal stenosis (narrowing of the spinal canal)
  • Spondylolisthesis (slippage of a vertebra)
  • Piriformis syndrome (compression of the sciatic nerve by the piriformis muscle in the buttocks)
  • Injury or trauma

Sciatica symptoms include:

  • Pain in the lower back, buttocks, and various parts of the leg and foot
  • Tingling or numbness
  • Weakness in the affected leg or foot

How a TENS machine works

A TENS unit consists of a small, battery-powered device that delivers electrical impulses through electrodes placed on the skin. The electrodes are typically connected to the TENS device by wires and are placed along the pathway of the affected nerve.

When the TENS unit is switched on, it delivers small electrical pulses that stimulate the nerves in the treatment area. This stimulation triggers the body to produce higher levels of its own natural pain-relieving chemicals, such as endorphins and encephalins.

Stimulating the nerves may also interrupt or “scramble” pain signals being transmitted to the brain. The combination of increased natural pain relief and disrupted pain signals can provide symptomatic relief for some sciatica patients.

Potential benefits of using a TENS unit for sciatica

Some research indicates TENS therapy may provide limited, short-term relief for chronic low back pain and associated sciatica. Potential benefits may include:

  • Reduced intensity of sciatic nerve pain
  • Fewer sciatica flare-ups
  • Decreased use of pain medication
  • Improved physical function
  • Enhanced ability to participate in physical therapy and exercise

A systematic review of studies found evidence that TENS provided small-to-moderate pain relief for chronic low back pain compared to placebo treatment. However, the duration of relief after using TENS tended to be fairly short.

Risks and concerns about using TENS for sciatica

While TENS therapy may provide temporary pain relief for some sciatica patients, there are also some potential downsides and risks to consider. These include:

  • Worsening pain – There is a risk that using a TENS unit could potentially aggravate sciatica symptoms in some cases or cause increased pain. This may occur if the device is set to an intensity level that is too high or irritating for the individual. Using TENS on inflamed nerves or at certain points in the course of recovery could also worsen pain.
  • Device misuse – If a TENS unit is not used properly, such as placing electrodes incorrectly or using improper settings, it may provoke muscle spasms and increase pain. Improper placement in the low back could potentially irritate the sciatic nerve.
  • Skin irritation – The electrodes may cause skin redness, burning or itching in some individuals, requiring repositioning.
  • Electric shock – Defective units could potentially deliver an electric shock and should not be used near water to avoid electrocution.
  • Interference with other electrical devices – TENS signals may disrupt pacemakers and other implanted medical devices.
  • Lack of long-term benefit – Research shows TENS tends to provide temporary relief during or shortly after use, but does not produce long-lasting sciatica pain reduction.
  • Delayed diagnosis/treatment – Relying solely on TENS for pain relief could potentially delay proper medical evaluation and more effective treatment of the underlying cause of sciatica.

Factors that may influence TENS effectiveness and risks

A number of factors may impact how well TENS therapy works for an individual’s sciatica symptoms and the potential risks.

Cause of sciatica

TENS may be more effective when sciatica is caused by muscle spasm or piriformis syndrome rather than a slipped disc or spinal stenosis. Underlying spinal abnormalities often require specific medical treatments beyond TENS for lasting relief.

Duration and severity of symptoms

TENS tends to work better for milder, acute sciatic pain and is less effective for severe, chronic nerve pain. Proper treatment of long-standing sciatica typically requires identifying and addressing the root cause.

Patient traits

Factors like the individual’s pain tolerance, sensitivity to electrical stimulation, and capacity to use the device correctly can affect TENS response. Elderly or medically fragile people may be at higher risk for certain side effects.

TENS settings

Placement of electrodes, stimulation intensity, and length of treatment can influence benefits and risks. Settings that are uncomfortable or overstimulate the sciatic nerve may provoke muscle spasms and worsen symptoms.

User error

Placing electrodes incorrectly, using too high intensity, or operating a defective device improperly are examples of user error that may cause a TENS unit to exacerbate sciatica pain.

Proper TENS machine technique

Using correct electrode placement and appropriate settings may help maximize potential benefits and minimize adverse effects from TENS therapy. Guidelines include:

  • Place electrodes parallel on either side of the sciatic nerve path, near the source of pain.
  • Avoid direct placement over the spine, inflamed nerves or broken skin.
  • Start stimulation intensity at a low setting and gradually increase to a comfortable level.
  • Adjust settings slowly and limit treatment to 30 minutes or less per session.
  • Move electrodes regularly to use on different areas and prevent skin irritation.
  • Keep the device away from water to prevent shocks.

TENS electrode placement for sciatica should target the lower back, buttocks and down the leg along the sciatic nerve pathway. Patients should be trained on proper device use by a medical professional.

Seeking guidance from a healthcare provider

It is advisable to consult a doctor or physical therapist before using a TENS unit for sciatic nerve pain. A physician can determine if TENS is appropriate and provide guidance on proper electrode placement and settings tailored to the individual.

Professional medical input is particularly important if sciatica symptoms are severe, persistent or worsening despite treatment. The provider may recommend pursuing alternative therapies, diagnostic testing or specialty referrals to identify and address the root cause of sciatica.

Other treatments beyond TENS

While TENS may offer temporary sciatica relief for some patients, other treatment approaches are often needed to provide sustained benefit. Additional options may include:

  • Prescription medications – Oral medications, injections or topical treatments to reduce inflammation and nerve pain.
  • Exercise/stretching – Specific exercises to strengthen the back and improve flexibility.
  • Physical therapy – Manual therapy techniques to improve mobility and reduce muscle tension.
  • Chiropractic care – Spinal manipulation or mobilization to improve alignment and nerve function.
  • Surgery – Procedures like microdiscectomy to correct underlying spinal abnormalities in severe, unresponsive cases.

Multidisciplinary treatment incorporating several complementary approaches typically provides the best long-term outcomes for persistent sciatica.


TENS therapy may offer temporary relief for some sciatica patients, but also has potential risks. Using a TENS unit improperly could potentially worsen sciatic nerve pain in some cases.

To maximize benefits and minimize risks, it is important to use appropriate TENS technique under medical guidance. Patients with severe or worsening sciatica should pursue a complete diagnostic workup and treatment plan beyond just TENS therapy.

While TENS may provide short-term symptomatic improvement, the best outcomes for chronic sciatica often require multiple therapies to resolve the underlying source of nerve compression or irritation.

Leave a Comment