comparison of electrotherapy methods to alleviate pain

An honest, guideline-accurate guide to TENS, ultrasound, shockwave, NMES and more — from the Chartered Physiotherapists at CK Physio in Hanwell, West London.

Reviewed: 28 July 2026 by the clinical team at CK Physio. All UK clinical guideline references verified current at time of publication.

Patients often arrive at our Hanwell clinic asking for “the machine that fixes my back” — the ultrasound, the TENS unit, the shockwave head. It's a completely understandable question. A device feels precise, modern and reassuringly technical.

Electrotherapy in Physiotherapy: What the Evidence Actually Shows

The evidence, though, tells a more nuanced story. Some electrotherapy modalities have a genuine, if modest, role. Others have been steadily downgraded by UK clinical guidelines. And a few have been on the “do not offer” list for years without patients being told.

We think you deserve the honest version. This guide walks through what each type of electrotherapy is, what the current UK evidence actually supports, and how we use these tools at CK Physio — always alongside the active rehabilitation, exercise and hands-on treatment that does the heavy lifting.

What is electrotherapy?

Electrotherapy is any physiotherapy treatment that uses electrical, sound or light energy applied to the body to influence pain, muscle activity or tissue healing. Under the Royal Charter, it sits alongside massage, exercise and “kindred methods” as one of the four pillars of physiotherapy in the UK.

The most common modalities you'll encounter are:

• TENS (transcutaneous electrical nerve stimulation) — a low current through the skin to help modulate pain signals.
• NMES / EMS (neuromuscular or electrical muscle stimulation) — a stronger current that makes a muscle actually contract, used mainly to rebuild strength after surgery.
• Therapeutic ultrasound — high-frequency sound waves applied via a hand-held probe.
• Interferential therapy (IFT) — two medium-frequency currents that cross inside the tissue.
• Low-level laser therapy (LLLT), also called photobiomodulation.
• Extracorporeal shockwave therapy (ESWT) — focused or radial pressure waves used mainly for stubborn tendon problems.
• Pulsed electromagnetic field therapy (PEMF), microcurrent, iontophoresis and short-wave diathermy — less commonly used and less well evidenced.

These are all “passive” treatments — they're done to you rather than by you. That distinction matters, because the best current evidence in UK physiotherapy consistently points to active treatments (graded exercise, movement retraining, education and self-management) as the foundation of recovery. Learn more on our introduction to how electrotherapy works.

Does NICE recommend electrotherapy?

For most common musculoskeletal conditions treated by physiotherapists, no. The picture is nuanced, but if we're being straight with you, this is what the current UK guidelines say.

In each of those guidelines, the recommended first-line treatments are the same: therapeutic exercise, education, self-management and (as part of a package) manual therapy. That's not us being contrarian — it's the current UK standard, and it's the framework we already use in every treatment plan.

There are two important exceptions, and it's worth being precise about them:

• Shockwave therapy (ESWT) has separate NICE HealthTech and interventional-procedure guidance covering refractory (stubborn, non-responding) plantar fasciitis, Achilles tendinopathy and tennis elbow. That's a narrow, condition-specific recommendation for cases that haven't responded to first-line care — not a blanket endorsement.
• NMES for post-surgical strength recovery (for example, after ACL reconstruction or knee replacement) has good-quality evidence for helping quadriceps muscle recovery when used alongside a proper exercise programme. Note that NMES is still on NG226's “do not offer” list for osteoarthritis — the post-surgical evidence is use-specific.

TENS also retains a legitimate role for short-term symptomatic pain relief during use, and it is widely and safely used for labour pain within the NHS. It is not, however, a cure, and it does not accelerate tissue healing.

A modality-by-modality guide

Here's what the current evidence actually supports for each of the main electrotherapy techniques, and how we use them (or don't) at CK Physio.

TENS (transcutaneous electrical nerve stimulation)

What the evidence says: A large 2022 systematic review of 381 randomised trials involving more than 24,500 participants found moderate-certainty evidence that pain intensity is lower during or immediately after TENS compared with placebo, with no serious adverse events. A Cochrane overview reached a more cautious conclusion for chronic pain overall — that it was not possible to conclude with confidence whether TENS was beneficial.

What NICE says: Do not offer TENS for osteoarthritis, low back pain/sciatica or chronic primary pain as a management strategy. TENS is separately supported by the NHS for use in labour.

How we use it at CK Physio: Occasionally, and only for short-term symptomatic pain relief when it clearly helps a specific patient stay active enough to keep doing their rehab. A home TENS unit can be a useful pain-management tool, but it's not a substitute for clinic-based physiotherapy. For a deeper look, see our guide to TENS machines: safety and effectiveness.

NMES / EMS (neuromuscular electrical stimulation)

What the evidence says: The strongest evidence for any electrotherapy modality in musculoskeletal care. A 2025 Level-1 systematic review of 11 randomised trials in patients recovering from ACL reconstruction showed that NMES added to standard physiotherapy significantly improved quadriceps strength at both short- and long-term follow-up, with the greatest benefit when started early. Similar findings exist for recovery after total knee replacement.

What NICE says: Do not offer NMES for osteoarthritis (NG226). The post-surgical rehab evidence sits outside that guideline.

How we use it at CK Physio: As an adjunct in post-surgical rehabilitation, particularly for restoring quadriceps strength when the muscle isn't yet firing well voluntarily. It's used alongside — never instead of — a progressive strengthening programme.

Therapeutic ultrasound

What the evidence says: One of the weakest evidence bases in the electrotherapy family. Cochrane reviews for chronic low back pain and knee osteoarthritis have found the evidence insufficient or of very low quality. Small, uncertain short-term benefits have been reported in some smaller studies, but overall the effect is at best modest and not well established.

What NICE says: Do not offer for low back pain and sciatica, osteoarthritis, or chronic primary pain.

How we use it at CK Physio: Rarely, and only in the limited circumstances where a specific clinical rationale exists. Many UK clinics have publicly phased ultrasound out; we're transparent that it is not a first-line tool here. For more, see our honest look at therapeutic ultrasound.

Interferential therapy (IFT)

What the evidence says: Widely used historically, but no high-quality systematic review supports it as a standalone treatment for common musculoskeletal pain.

What NICE says: Do not offer for low back pain, osteoarthritis or chronic primary pain.

How we use it at CK Physio: Very selectively, and never as the main event. Our page on interferential therapy explains the historical context and how our thinking has moved on.

Low-level laser therapy (LLLT / photobiomodulation)

What the evidence says: Mixed and largely low-certainty. Recent systematic reviews suggest modest reductions in pain and improvements in function across a range of conditions, but the protocols vary widely and overall confidence in the effect is limited.

What NICE says: Do not offer for osteoarthritis (listed under “laser therapy” in NG226).

How we use it at CK Physio: Not routinely. Where a patient is curious, we're honest about the uncertainty.

Extracorporeal shockwave therapy (ESWT)

What the evidence says: The best-evidenced device modality for specific stubborn tendon problems. Systematic reviews support its use for lower-limb and calcific tendinopathies; it appears less effective for upper-limb, non-calcific tendon problems. A meaningful minority of patients don't respond, and the mechanism by which it works is still not fully understood.

What NICE says: NICE HealthTech and interventional-procedure guidance support ESWT for refractory plantar fasciitis (HTG200), Achilles tendinopathy (HTG426) and tennis elbow (IPG313). This is a narrower endorsement than some clinics imply — it applies to cases that haven't responded to first-line treatment, not as a routine first option.

How we use it at CK Physio: As one of the more useful device-based tools available — but always delivered as part of a progressively loaded exercise programme, not on its own. Explore our shockwave therapy service, and if you're wondering what to expect, our guide to whether shockwave therapy is painful is a good starting point.

PEMF, microcurrent and iontophoresis

These are emerging or historical modalities with limited, low-certainty evidence. They are not mainstream UK physiotherapy tools, and we don't rely on them for musculoskeletal recovery.

Is electrotherapy safe?

In the right hands and with the right patient, electrotherapy is generally very safe. Reported side effects are typically mild — skin irritation, tingling, temporary redness — and serious adverse events are rare. That said, there are important situations in which electrotherapy should be avoided or approached with extra care.

Situations where electrotherapy is not appropriate:

• If you have a cardiac pacemaker, implantable defibrillator, ventricular assist device or other implanted electronic device.
• Over the front of the neck, over the eyes, over the mouth, over the heart or internally.
• Over broken, damaged, infected or numb skin.
• While driving, operating machinery, in the bath or shower, swimming, or sleeping.

Situations that need caution and a proper assessment first:

• Pregnancy — not over the abdomen, pelvis or lower back. TENS in labour is considered safe under professional guidance.
• Epilepsy — avoid electrodes on the neck or head; uncontrolled epilepsy is generally an exclusion.
• Active cancer — do not apply locally over a tumour site. If you have undiagnosed pain and a history of cancer, TENS should not be used until you've been reviewed medically.
• Bleeding disorders.

Please always disclose implants, pregnancy and any active medical conditions at your initial assessment. If you're using a home TENS unit, the NHS advises checking for a CE or UKCA safety mark before you buy.

How we use electrotherapy at CK Physio

Our approach is straightforward: electrotherapy is an adjunct, not the treatment. The treatment is you, moving well, guided by a Chartered Physiotherapist who understands your goals and your history.

In practice, that means every plan we build follows the same evidence-led hierarchy:

1. Graded exercise, tailored to you. This is the single most consistent finding across UK guidelines for musculoskeletal pain, and it forms the foundation of every rehabilitation plan we design.
2. Education and self-management. Understanding what's happening in your body — and what you can do about it — is one of the strongest predictors of a good recovery.
3. Hands-on manual therapy where clinically indicated, as part of a wider package.
4. Electrotherapy, chosen selectively for the specific situations where the current evidence supports it — most commonly shockwave for refractory tendinopathies, NMES for post-surgical strength recovery, or TENS for short-term pain modulation to keep you active.

You can see the full picture on our electrotherapy service page, and if you'd like to understand our wider philosophy of care, our main physiotherapy service page is a good place to start. Athletes and active patients may also want to read about our sports physiotherapy service in West London.

Frequently asked questions

References

1. National Institute for Health and Care Excellence. Osteoarthritis in over 16s: diagnosis and management (NG226). Published 27 October 2022. https://www.nice.org.uk/guidance/ng226
2. National Institute for Health and Care Excellence. Low back pain and sciatica in over 16s: assessment and management (NG59). Published 30 November 2016; last updated 11 December 2020. https://www.nice.org.uk/guidance/ng59
3. National Institute for Health and Care Excellence. Chronic pain (primary and secondary) in over 16s: assessment of all chronic pain and management of chronic primary pain (NG193). Published 7 April 2021. https://www.nice.org.uk/guidance/ng193
4. National Institute for Health and Care Excellence. Extracorporeal shockwave therapy for refractory plantar fasciitis (HTG200). https://www.nice.org.uk/guidance/htg200
5. National Institute for Health and Care Excellence. Extracorporeal shockwave therapy for refractory Achilles tendinopathy (HTG426). https://www.nice.org.uk/guidance/htg426
6. National Institute for Health and Care Excellence. Extracorporeal shockwave therapy for refractory tennis elbow (IPG313). https://www.nice.org.uk/guidance/ipg313
7. Johnson MI, Paley CA, Jones G, Mulvey MR, Wittkopf PG. Efficacy and safety of transcutaneous electrical nerve stimulation (TENS) for acute and chronic pain in adults: a systematic review and meta-analysis of 381 studies (the meta-TENS study). BMJ Open 2022;12(2):e051073. https://pubmed.ncbi.nlm.nih.gov/35144946/
8. NHS. Transcutaneous electrical nerve stimulation (TENS). https://www.nhs.uk/conditions/transcutaneous-electrical-nerve-stimulation-tens/
9. Chartered Society of Physiotherapy. Professional guidance and standards. https://www.csp.org.uk/
10. Health and Care Professions Council. Standards of proficiency: Physiotherapists. https://www.hcpc-uk.org/
11. Advertising Standards Authority. Ruling on Cheshire Health & Medical Professionals LLP (Nantwich Clinic), 15 September 2021 — on evidence standards for electrotherapy claims. Read the ruling