Updated: Dec 19, 2020
Today's topic is based on a January 2020 publication and when I saw this systematic review was published, I knew I would enjoy doing a blog on this particular review. I'll give you the title of the review right off the top here. It's called "The Beneficial Effects of High Intensity Laser Therapy and Co-interventions on Musculoskeletal Pain Management: a Systematic Review." This was published in the Journal of Lasers and Medical Sciences in January of this year, January of 2020. I've heard occasionally that high-intensity laser therapy just doesn't have enough evidence behind it, like low intensity laser does. And really that can be answered by saying, that these have the same effects. Even the dosage is the same. The major difference between high intensity laser therapy and low intensity laser therapy is that the lower power treatments just take longer to apply.
Cold Laser vs. Class 4 Laser
And a matter of fact, I'll read you a quote from this study. They say the main difference between high intensity laser and low power laser is that "the more powerful beams are irradiated to penetrate deeper, bringing a desired high amount of multi-directional energy to deep tissues in a short time." So, we're also talking about penetration there and saying that higher intensity means we can, as a matter of fact, penetrate deeper, which is quite exciting when we're talking about treating deeper injuries. And just to make sure that I'm giving you enough info here, we're not talking about surgical lasers. We're not talking about even cosmetic lasers. We're not ablating or super heating any of the tissues. There can sometimes be a little bit of a thermal effect from Class 4 lasers, high intensity lasers, but even LED light therapy can generate quite a bit of warmth and give you some level of thermal effect. But the point here is that the light that you're driving into the tissues, the infrared light you're driving into the tissues, stimulates a number of responses in the cells of the damaged area you're talking about. And that promotes healing.
And so, when we're talking about low power laser versus high intensity laser, is there really a difference? Well, the main difference is not in the way that the light works. The main difference is the time that it takes to deliver the treatment and how deep you can get into the tissues with that. In the systematic review, they started with 52 studies and then filtered them down based on quality controls and ended up with 19 studies they felt were of high enough quality to include with the study and all these studies were on musculoskeletal pain conditions. And they found that 94% of these studies revealed positive effects of laser therapy on pain. That's that's a pretty big deal, especially when you consider that the main cause of pain in adults is a musculoskeletal pain condition.
NSAIDs Affect Results
So not only is laser therapy effective in the high intensity ranges, but they also looked at a couple of other interesting facts here and they found that laser therapy results could be drastically affected by the presence of non-steroidal anti-inflammatory drugs. So, patients who are getting high intensity laser therapy and also taking NSAIDs got much poorer results than those who were just doing laser therapy. And given the fact that they had 19 of these studies, they were also able to say that if you're doing high-intensity laser, you should be somewhere in the neighborhood of at least 10 sessions. And you should be using laser settings that include pulsed light, not just continuous wave light. Pulsing can be anywhere from one Hertz, two Hertz, all the way up to even 20,000 Hertz, or 20,000 flashes within a second. And that tends to have, according to these researchers, better effects overall.
Making Laser Therapy Work
Now a lot of the studies that they looked at didn't only include laser therapy, but they also included some other co-interventions as well. Now a very common co-intervention with laser therapy is exercise therapy. So, these researchers took the studies that had laser therapy with exercises. And looked at those a little bit separately from laser therapy plus anything else. And what they found is that with laser therapy and exercise, they had very good effects on osteopenia, plantar fasciitis, and osteoarthritic knees. In the group of studies where they did laser therapy and then other interventions, like interferential and other passive modalities, they saw best results with chronic back pain, juvenile rheumatoid arthritis, and wound healing, which makes sense. Right? I mean, you're not going to give exercises to a patient for wound healing. There's not really any point in doing that.
And another finding they were able to see by looking at all these different studies was that "we should apply more irradiance of laser therapy in chronic pain conditions." Now irradiance means the amount of light that's delivered to tissues. And it's a function of the power of the light as well as the time that the light is applied, and the total area covered.
So, given all this, the fact that NSAIDs tend to reduce effects of laser, that laser therapy sessions should be about 10 or more, and that you should be using pulsed light that you should use higher irradiance for the chronic patient versus the acute pain patient. All these different things really fit into the art of applying laser. And it can take some knowledge, it can take some practice to really get pretty good at this. Laser Therapy Institute programs give you a shortcut to that. You can jump right in with protocols that you know are going to work, help you troubleshoot patients who aren't responding like you think they should, and make sure that their outcomes are all going to be better than guessing and hoping.
Again, we're looking at the evidence, we have more and more evidence every year that laser therapy works. And in this case specifically that high-intensity laser therapy can work and high-intensity laser therapy treatments being shorter and delivering deeper penetrating light means they should be easier to apply in clinic for you and your staff and they should work better. If you have questions on how to get better at your patient results with laser therapy, what kind of equipment you should be looking at, please get in touch with us. And I'll look forward to speaking with you again next week.