The short version.
- Therapeutic ultrasound passes high-frequency sound waves through a small handheld head held against the skin. It warms a small patch of tissue near the surface and adds a gentle vibration, and the research for a strong deep effect is widely considered weak.
- TECAR uses a radiofrequency electrical current at around 500 kHz that flows through the body, so it can warm a larger volume of deeper tissue rather than only the area right under an applicator.
- The honest difference is depth and treated volume, which is why some clinics have moved beyond routine ultrasound for deeper work, even though the evidence for TECAR is still developing.
- Both are passive treatments that warm tissue. Neither replaces the active exercise and hands-on rehabilitation that does the lasting work.
How therapeutic ultrasound works.
Therapeutic ultrasound is one of the oldest machines you will find in a physiotherapy clinic. The therapist puts a thin layer of gel on the skin, then moves a small handheld head slowly over the sore area. That head sends out high-frequency sound waves, meaning sound at a pitch far above what a person can hear. As those waves pass into the tissue, they create a small amount of heating and a gentle mechanical vibration in the area right under the applicator.
The treated area is small because it follows the size of the handheld head, and the effect is strongest close to the surface. For some people the warmth feels soothing and can take the edge off a sore spot for a while. The harder question is whether that produces a real change in a deeper muscle or a thick tendon. High-quality studies have struggled to show a strong deep result for many common problems, and that is the main reason a lot of clinics no longer lean on ultrasound for serious deep work. It is not that it does nothing. It is that the deep benefit is hard to demonstrate.
How TECAR works by comparison.
TECAR takes a different route to the same goal of warming tissue. Instead of sound waves, it uses a radiofrequency electrical current at around 500 kHz. The therapist moves a conductive electrode over the skin while a return plate completes the circuit on another part of the body, so the current flows through the tissue between the two points. As the current passes through, it stirs up the charged particles inside the tissue, and that friction generates heat from within rather than only at the surface.
Because the energy travels through a region rather than sitting under a small head, TECAR can warm a larger volume of deeper tissue. That is the core difference. For a deep muscle belly, a thick tendon, or the soft tissue around a joint, reaching that depth can make the hands-on treatment and exercise that follow feel more comfortable. We are careful not to overclaim here. The evidence for TECAR is promising but still maturing, and we use it as one supporting tool, not a cure. The page on how TECAR works walks through the mechanism in more detail.
Side by side.
| TECAR | Therapeutic ultrasound | |
|---|---|---|
| Mechanism | Radiofrequency electrical current at around 500 kHz flows through the tissue, with the body completing the circuit, generating heat from within. | High-frequency sound waves from a small handheld head create mild heating and a gentle vibration in the tissue under it. |
| Depth reached | Aims to warm deeper tissue, since the current passes through the region rather than sitting on the surface. | Strongest closer to the surface, with a more limited deep effect. |
| Energy delivered | Spread through a larger volume of tissue between the electrode and the return plate. | Concentrated in the small patch under the handheld applicator. |
| Evidence picture | Promising but still developing, with mostly small studies that suggest short-term help as part of a plan. | Widely considered weak for a strong deep effect on many common muscle and tendon problems. |
| Where each fits | A supporting tool for warming deeper tissue before hands-on work and exercise. | A gentle, surface-level comfort option that some people still find soothing. |
Why depth and treated volume differ.
The reason the two reach different depths comes down to how the energy moves. Ultrasound relies on sound waves entering the tissue from one small head, so the energy is concentrated in the patch right beneath that head and fades as it goes deeper. TECAR, by contrast, sets up a current that travels through the body between the electrode and the return plate. Because the path runs through a region rather than stopping at the surface, the heat builds across a larger volume of tissue.
This is the practical difference that has led some clinics to move beyond routine ultrasound for deeper problems. If the tissue you are trying to reach sits well below the skin, a tool that warms a wider, deeper area can be a better match than one that mainly warms the surface. We still keep our claims modest. Reaching deeper tissue is useful, but it is the active rehabilitation that follows that turns that warmth into progress you keep. For an honest look at what the studies actually show, see our page on TECAR evidence and research.
Both are passive, so neither stands alone.
It is worth being clear that both TECAR and therapeutic ultrasound are passive treatments, which means you rest while the machine works. Passive heat can ease pain and loosen stiff tissue for a while, but on its own it rarely fixes the underlying problem. The lasting change comes from active rehabilitation, meaning the loading and exercise that rebuild strength and the tissue's tolerance for the demands you place on it.
That is how we use any warming tool at Medstar. It sets the stage so that the hands-on treatment and the exercise plan are more comfortable and more productive. If a tool ever gets in the way of doing the active work, it is not earning its place. You can read more about the plan these tools support on our physiotherapy page, and for general health guidance in British Columbia you can check HealthLinkBC.
Common questions.
Is TECAR just a stronger version of therapeutic ultrasound?+
No. They are different technologies that happen to share the same goal of warming tissue. Therapeutic ultrasound uses high-frequency sound waves passed through a small handheld head, while TECAR uses a radiofrequency electrical current at around 500 kHz that flows through the body between an electrode and a return plate. Because the energy source is different, the depth and the volume of tissue that warms up are also different. So it is fairer to call them two separate tools rather than one being a bigger version of the other.
Does that mean therapeutic ultrasound does not work at all?+
Not quite. Ultrasound can produce mild local heating and a gentle vibration in the tissue right under the applicator, and some people find it soothing. The honest issue is that high-quality research has struggled to show a strong deep effect on common muscle and tendon problems, which is why many clinics no longer rely on it for deeper work. It is not useless, but the evidence for a meaningful deep result is widely considered weak. We would rather tell you that plainly than oversell any single machine.
Why would a clinic choose TECAR over ultrasound for a deep problem?+
The main reasons are depth and treated volume. Ultrasound warms a small patch of tissue near the surface under the handheld head, whereas TECAR aims to warm a larger volume of deeper tissue because the current passes through the area rather than sitting on top of it. For a deep muscle, a thick tendon, or tissue around a joint, that larger warmed area can make the hands-on treatment and exercise that follow more comfortable. That said, TECAR is still a supporting tool, not a cure, and the evidence behind it is promising rather than settled.
Are both treatments passive, and does that matter?+
Yes, both are passive, which means the machine does the work while you rest. That matters because passive heat alone rarely fixes an injury on its own. The lasting improvement comes from active rehabilitation, meaning the exercise and loading work that rebuilds strength and tolerance. We use any heating tool to make that active work easier and more comfortable, never as a replacement for it.
Can I get TECAR near Vancouver?+
As far as we are aware, Medstar Sport Physio and Health in North Vancouver is the only clinic in the Metro Vancouver area that offers TECAR therapy. People often travel across the North Shore to try it as part of a physiotherapy plan. You can call the front desk at (604) 988-5411 or book online if you want to talk through whether it suits your specific problem.
Related reading
The only TECAR on the North Shore