High intensity laser therapy
The laser is a tool, not a miracle.
Medstar was the first physiotherapy clinic on the North Shore to install a Class 4 high intensity laser. This hub explains what it does, which injuries the research actually supports, and when we would tell you to spend your money on something else.
In short
High intensity laser therapy, in eight lines.
- High intensity laser therapy, HILT, HPLT, high-power laser, and Class 4 laser are five names for the same treatment.
- Class 4 is a safety classification under the international laser standard. It tells you the device needs protective eyewear, not that it is clinically superior.
- The mechanism is photobiomodulation: red and near-infrared light absorbed by mitochondria, shifting the local cell environment toward repair.
- The strongest evidence is in lower-limb tendinopathy and plantar fasciitis, where a 2022 BMJ Open review measured a 13.15 mm reduction in pain on a 100 mm scale.
- Evidence in knee osteoarthritis is moderate and works best alongside exercise. Evidence in chronic low back pain is weaker again.
- A course usually runs 6 to 10 sessions, with most people noticing a change around the third or fourth.
- Everyone in the room wears protective eyewear, because a Class 4 beam can damage the retina if viewed directly.
- Laser is billed inside a physiotherapy visit, so ICBC, WorkSafeBC, and extended health cover it on the physiotherapy line with no separate laser fee.
The short version
What the machine actually does.
A therapeutic laser produces light at specific wavelengths in the red and near-infrared range. That light is absorbed inside your cells, mainly by an enzyme in the mitochondria. The absorption changes how the cell behaves for a while: more energy production, less of the local chemistry that keeps an area sore and swollen. The formal name for this is photobiomodulation. It is a biological effect, and it is a modest one.
The word “high intensity” is about power, not about aggression. A Class 4 device puts out more optical power than the small Class 3B units sold for home use, which means more light energy reaches tissue underneath skin and fat in the same amount of time. Deep structures like a hip tendon or the back of a knee are reachable in a way they are not with a low-power device. That is the entire practical difference.
Here is the part most clinic websites leave out. Laser does not restructure tissue in a session, it does not block nerve signals, and it does not replace loading. What it does reasonably well is lower pain and irritability for a period of time, which matters because it lets you start doing the rehab that genuinely changes a tendon or a joint. If a clinic sells you laser as the treatment rather than as the thing that makes treatment possible, be skeptical.
We use it most in three situations: an acutely irritable injury in its first few weeks, a post-surgical area that is too sore to load properly, and a chronic joint problem like knee osteoarthritis or a frozen shoulder where pain is the reason you cannot get moving. Outside those, we will often tell you your money is better spent on assessment time and a loading programme.
The full guide
Everything about laser therapy, in plain English.
Start here
Start here
What high intensity laser therapy actually is
HILT, HPLT, Class 4, photobiomodulation: five names for one treatment. What the laser class number means, what the light does inside tissue, and what it cannot do.
Start here
What a laser session feels like
Start to finish: the safety eyewear, the warmth, how long the laser portion runs, how many sessions a course takes, and what you are allowed to do afterwards.
What it treats
Evidence
Does laser therapy actually work? What the evidence says
Where the published trials are strong, where they are mixed, and where they are weak. Real numbers from the meta-analyses, including the ones that do not favour laser.
Conditions
Laser for tendinopathy and plantar fasciitis
The strongest evidence case for laser: Achilles, patellar and shoulder tendinopathy, tennis elbow, and plantar fasciitis, and why dose is the thing that decides the result.
Conditions
Laser for knee osteoarthritis and frozen shoulder
Two joint conditions where laser is used to make movement tolerable enough to start real rehab, and an honest read of how good the supporting evidence is.
Practical questions
Safety
Is laser therapy safe? Side effects and who should avoid it
Why everyone in the room wears eyewear, the side effects that are normal, the ones that are not, and the specific situations where we will not use the laser on you.
Money
Laser therapy cost and insurance coverage in BC
How laser is billed inside a physiotherapy visit, what that means for ICBC, WorkSafeBC, and extended health, and why we do not sell session packages.
Related
Where laser fits with everything else.
- Laser therapy service page: booking, what to expect at your first visit, and the conditions we see most.
- TECAR therapy: the other deep-tissue machine we run, and the one laser is most often confused with.
- Shockwave therapy: mechanical rather than light-based, and the better choice for stubborn chronic tendinopathy.
- Journal: what high-power laser treats: our longer clinical write-up on the evidence, with sources.
FAQ
Laser therapy questions we get asked.
Does high intensity laser therapy actually work?
High intensity laser therapy has its strongest published support in lower-limb tendinopathy and plantar fasciitis. A 2022 BMJ Open systematic review of randomised trials found laser reduced pain by 13.15 mm on a 100 mm visual analogue scale at the end of treatment, and the benefit was still measurable 4 to 12 weeks later. That is a real effect, though a modest one, and it was measured alongside rehab rather than instead of it.
What is the difference between high intensity laser, HILT, HPLT, and Class 4 laser?+
High intensity laser therapy, HILT, HPLT, high-power laser, and Class 4 laser all describe the same treatment. European research papers tend to write HILT, North American clinics tend to say high-power or Class 4. Class 4 is a laser safety classification, not a brand or a clinical grade. The device, the mechanism, and the conditions treated are identical whichever term a clinic puts on its website.
What does laser therapy feel like?+
High intensity laser therapy feels like a deep, spreading warmth over the treated area, and most people find it pleasant. The handpiece keeps moving in slow passes rather than sitting still, which is what stops any single spot getting too hot. Sharp pain or a burning sensation is not expected. If you feel either, say so immediately and your physiotherapist will change the pass speed or reposition the head.
How many laser sessions will I need?+
A course of high intensity laser therapy at Medstar usually runs 6 to 10 sessions, often two to three times a week at first and then spacing out. The cellular response is cumulative, so most people notice a shift around the third or fourth session rather than the first. We reassess after the first block and stop if nothing measurable has changed. We do not pre-sell session packages.
Is laser therapy safe?+
High intensity laser therapy is safe when it is delivered by a trained clinician with the correct eyewear on everyone in the room. A Class 4 laser can damage the retina if the beam is viewed directly, so protective glasses are not optional for either the patient or the operator. Beyond eye safety, the common side effect is short-lived warmth or mild redness over the treated area.
How do I know if laser therapy is right for my injury?+
You find out at an assessment rather than by booking a course of laser up front. High intensity laser suits an injury where pain and irritability are the specific barrier stopping you from loading the area, such as a reactive tendon or a painful arthritic knee. If your main problem is stiffness, weakness, or movement control, a physiotherapist should tell you plainly that laser is not the answer.
Is laser therapy covered by ICBC, WorkSafeBC, or extended health?+
Laser is delivered inside a physiotherapy session at Medstar and billed on the physiotherapy line, so normal funding rules apply. ICBC claims, WorkSafeBC claims, and most extended health plans cover physiotherapy visits that happen to include laser. There is no separate laser fee added on top, and no funder is billed for laser as its own line item.
Is laser therapy better than shockwave?+
Laser and shockwave do different physical jobs, so one is not simply better. Laser delivers light that is absorbed by tissue and is generally comfortable, which suits irritable or acutely inflamed problems. Shockwave delivers mechanical pressure waves and is deliberately more provocative, which suits stubborn chronic tendinopathy and calcific deposits. The choice depends on how irritable your tissue is on the day you are assessed.
Do I need a separate appointment for laser therapy?+
No. Laser at Medstar happens inside a regular physiotherapy appointment, not as a standalone booking. The laser portion takes 10 to 20 minutes of the visit, and the rest is assessment, hands-on treatment, and your loading programme. The point of the laser is to make the rehab tolerable sooner, so separating the two would defeat the purpose.
How soon after an injury can I start laser therapy?+
High intensity laser therapy can begin as soon as you have been assessed and serious injury has been ruled out, and there is no waiting period built into the treatment itself. We use it most in the first few weeks after an injury, when pain and swelling are at their peak and are the reason you cannot start rehabilitation. Book an assessment first so the diagnosis comes before the machine.
Not sure it is for you?
Come in for an assessment and we will tell you honestly whether the laser helps.
Some injuries respond well to it. Plenty do not, and we will say so rather than sell you a package. Either way you leave with a plan.