TENS Units for Joint Pain: How They Work and When They Help

Key Takeaways

TENS (Transcutaneous Electrical Nerve Stimulation) delivers mild electrical currents to reduce pain
Research shows modest but real benefits for many people with joint pain
TENS is safe, drug-free, and can be used at home
Units are affordable ($30-$100) and available without prescription
Proper electrode placement and settings are key to effectiveness
Works best as part of a comprehensive pain management approach

If you’re looking for drug-free pain relief you can control yourself, a TENS unit might be worth trying. These portable devices have been used for decades to manage various types of pain, including arthritis and joint discomfort.

This guide explains how TENS works, what evidence supports its use, and how to get the best results.

What Is TENS?

How It Works

TENS stands for Transcutaneous Electrical Nerve Stimulation. The device:

Delivers mild electrical pulses through electrodes placed on your skin
The pulses stimulate nerves in the area
This stimulation is thought to reduce pain perception

Proposed Mechanisms

Gate Control Theory: The most commonly cited explanation. Electrical stimulation activates large nerve fibers that “close the gate” to pain signals, preventing them from reaching the brain. Think of it as the nerves being too busy processing the TENS sensations to transmit as much pain.

Endorphin Release: Lower frequency TENS may stimulate the release of endorphins—your body’s natural painkillers. This may explain why effects sometimes last beyond the treatment period.

Other Effects:

May increase blood flow to the area
May reduce muscle tension
May interrupt chronic pain patterns

What Does Research Show?

Evidence Summary

For knee osteoarthritis:

Multiple studies show modest pain reduction
Benefits are greater than placebo in most studies
Effects may last hours to days after treatment
Not a cure, but can help manage symptoms

Overall pain research:

TENS is one of the most studied non-drug pain treatments
Results are mixed but generally positive
Works better for some people than others
Few adverse effects reported

What “Modest Benefit” Means

Typically 20-30% pain reduction for responders
May allow reduction in pain medication
Improvements in function and activity tolerance
Some people experience significant relief, others minimal
Low-risk intervention worth trying

Guidelines

American College of Rheumatology (2019):

Conditionally recommends TENS for knee OA
Considered appropriate, especially when medications are insufficient or not preferred

Types of TENS Units

Conventional TENS

Settings:

High frequency (50-150 Hz)
Low intensity (comfortable tingling)
Continuous mode

Characteristics:

Most common type
Immediate pain relief while in use
Effects may not last long after stopping
Can be used for extended periods

Acupuncture-Like TENS (ALT)

Settings:

Low frequency (1-10 Hz)
Higher intensity (muscle twitching visible)
Burst or modulated modes

Characteristics:

May stimulate endorphin release
Effects may last longer after treatment
Sessions typically shorter (20-30 minutes)
More intense sensation

Many Units Allow Both Approaches

Modern TENS units often let you adjust settings to try both approaches and find what works best for you.

Choosing a TENS Unit

Features to Consider

Basic units ($30-$50):

Preset programs
Basic intensity control
Adequate for most users

Mid-range units ($50-$100):

More customizable settings
Multiple channels (treat multiple areas)
Rechargeable batteries
Timer functions

High-end units ($100+):

Extensive programs
Combination TENS/EMS
App connectivity
Not necessary for most home users

What You Need

For home use with joint pain:

At least 2 channels (4 electrodes)
Adjustable intensity
Adjustable frequency or preset programs
Clear instructions
Quality electrodes included

Where to Buy

Pharmacies and drug stores
Online retailers (Amazon, etc.)
Medical supply stores
Some physical therapy offices

No prescription is required for basic TENS units in the US.

Using Your TENS Unit

Electrode Placement for Joints

Knee:

Place electrodes on either side of the knee
Above and below the kneecap
On the inner and outer knee
Avoid placing directly on the kneecap

Hip:

Around the hip joint
On the buttock and outer hip
Above and below the joint line

Shoulder:

Above and below the joint
Front and back of shoulder area
Avoid the chest if you have heart conditions

Hand/Wrist:

On either side of the wrist
On the back of the hand
Around specific painful areas

General Placement Tips

Place electrodes on either side of the painful area
Keep electrodes at least 1 inch apart
Clean, dry skin improves contact
Don’t place over open wounds or irritated skin
Avoid bony prominences directly

Settings to Try

Start with:

Medium frequency (50-80 Hz)
Low intensity (comfortable tingling, not pain)
20-30 minute sessions

Adjust based on response:

If immediate relief fades quickly, try lower frequency
If not enough effect, gradually increase intensity
Try different electrode positions

How Often to Use

Can be used multiple times daily
20-45 minute sessions typical
Some people use during activities
No established maximum, but give skin breaks
Listen to your body

Safety Considerations

TENS Is Generally Very Safe

Minor issues:

Skin irritation under electrodes (use quality electrodes, move positions)
Mild discomfort if intensity too high (reduce intensity)
Allergic reaction to electrode gel (try hypoallergenic electrodes)

Who Should NOT Use TENS

Absolute contraindications:

Pacemaker or implanted defibrillator (unless cleared by cardiologist)
Over areas of cancer (theoretical concern)
On the abdomen during pregnancy
On the front of the neck (affects blood pressure and breathing)
Over the eyes

Use with caution:

Epilepsy
Heart disease (discuss with doctor)
Over areas of decreased sensation (can’t feel if too intense)
Near electronic monitoring equipment

When to Stop and Consult a Doctor

Skin reaction that doesn’t resolve
Unusual symptoms during use
Increasing pain with use
Any concerning symptoms

Tips for Best Results

Optimize Your Technique

Experiment with placement: Small changes can make big differences
Try different frequencies: What works varies by person
Use adequate intensity: Strong but comfortable
Be consistent: Regular use often provides best results
Combine with movement: Some people benefit from using TENS during exercise

Track Your Response

Note pain levels before and after
Record settings that work best
Notice how long relief lasts
Adjust based on patterns

Common Mistakes

Intensity too low: The sensation should be clear and noticeable
Poor electrode contact: Clean skin and quality electrodes matter
Giving up too soon: Try different settings before concluding it doesn’t work
Using as sole treatment: Works best alongside other approaches

TENS as Part of Your Treatment Plan

Combines Well With

Exercise and physical therapy
Heat or ice
Topical treatments
Oral medications (may allow lower doses)
Other treatments like injections

When TENS May Be Particularly Helpful

When you can’t take or want to reduce pain medications
For breakthrough pain between other treatments
During physical therapy or exercise
For traveling (portable and drug-free)
At night for sleep-disrupting pain

Frequently Asked Questions

How quickly does TENS work?

Most people notice effects within minutes of starting treatment. Maximum benefit often develops over 15-30 minutes. How long relief lasts after treatment varies—anywhere from minutes to hours or longer.

Can I use TENS too much?

There’s no established maximum, but your skin needs breaks from electrodes. Continuous use can cause irritation. Most people use TENS in sessions throughout the day rather than continuously.

Does TENS actually treat the underlying arthritis?

No. TENS manages pain but doesn’t change the underlying joint condition. It’s a symptom management tool, not a disease-modifying treatment. This is true of many pain treatments.

Why doesn’t TENS work for everyone?

Pain is complex, and response to any treatment varies. Factors may include:

Type and severity of pain
Individual nerve response patterns
Proper vs. improper use
Expectation and placebo response
Whether optimal settings have been found

Can I use TENS with other treatments?

Generally yes. TENS is compatible with most other treatments. However, tell your physical therapist or doctor if you’re using TENS, as they may want to coordinate timing with other interventions.

Is EMS the same as TENS?

No. EMS (Electrical Muscle Stimulation) targets muscles to cause contraction, used for strengthening or rehabilitation. TENS targets sensory nerves to reduce pain. Some units combine both functions.

Looking for other pain relief options? Explore our guides on heat vs. ice for joint pain or learn about topical treatments.

Last medically reviewed: February 2025

Medical Disclaimer: This article is for informational purposes only. While TENS units are available without prescription, discuss their use with your healthcare provider, especially if you have a pacemaker, heart condition, or other medical concerns.