IFT, ultrasound and TENS machines: do they actually help?

The most common machines are IFT (interferential therapy, which passes a mild electrical current through the painful area), therapeutic ultrasound (a probe moved over the skin with gel), TENS (a small electrical stimulator, often battery-powered) and heat, usually a hot pack or infrared lamp. Some clinics add traction or short-wave diathermy.

These treatments are easy to deliver to many patients at once, they feel like something is being done, and patients often expect them. That is a large part of why they are so common. But how a treatment feels on the day is not the same as whether it helps you recover.

For most common problems such as back pain, neck pain and knee osteoarthritis, research has found little or no lasting benefit from therapeutic ultrasound or interferential therapy compared with a sham (switched-off) machine. TENS can ease pain for a short time in some people, but the effect usually fades soon after it is switched off.

The UK's National Institute for Health and Care Excellence (NICE), for example, advises against offering TENS, ultrasound or interferential therapy for low back pain. Guidelines in other countries say much the same: the treatments with the best evidence are exercise, advice on staying active, and in some cases hands-on therapy alongside exercise.

Heat is different. A hot pack or hot water bottle can genuinely ease stiffness and muscle spasm for a while, and it is safe and cheap to do at home. It is a comfort measure, not a cure.

Machines are not harmful when used correctly, and they can have a small role. TENS or heat can take the edge off pain so that someone can start moving. Some specific uses, such as electrical stimulation to help activate a muscle after surgery or nerve injury, are a different thing from IFT for back pain and can be useful.

The problem is when machines are the main treatment, session after session, and the exercises that would build strength and confidence are skipped or reduced to a printed sheet.

A good session starts with an assessment: what hurts, what makes it better or worse, what you cannot do that you want to do, and a safety screen for problems that need a doctor. Then most of the time goes on active treatment: exercises chosen for your problem, checked and corrected while you do them, and progressed as you improve.

You should leave knowing what is wrong in plain language, what to do at home and how much, and what to expect over the coming weeks. If you have had ten sessions of machines and nobody has watched you exercise, it is fair to ask why.

This is also why physiotherapy works well on a video call. Assessment, exercise, correction and advice do not need machines, and they are the parts that make the difference.