For the last 18 months, I’ve been involved in chronic pain education for the division of Family Practice Physicians. Pretty much every talk I gave, I got asked about Laser and if I felt it was beneficial. My standard reply was “I’ve not reviewed the literature so I can’t give an informed decision”. I’m due to give a few more presentations throughout the lower mainland over the next few months so thought it was about time I had a quick look as I know it’ll come up again!
Doing a quick literature search and a scan of some abstracts, it appeared that Laser offered outstanding results, however, a closer look at some of the methodologies left me questioning some of the conclusions. Many of the studies touting great benefits were low in subjects (not many people in the study), not blinded (meaning that subjects knew if they were either receiving or not receiving Laser) and offered no comparison group (eg no sham Laser group). This is important to note as these methodologies mean that any results have to be taken very lightly (no pun intended). So on to a slightly more in depth review...
Laser for rotator cuff tendinopathy:
A recent systematic review and meta-analysis by Boudreault et al (2016) analyzed 13 RCT’s (randomized control trials). Their findings suggested that laser may provide slightly better pain relief (of minimal clinical significance) than clinical recommendations (advice) alone, but offers no advantage in self reported shoulder function or range of movement. When laser was used in conjunction with exercise, it offered no superior benefits to exercise alone in regards to pain, function or range of movement.
Doyle et al (2016) provided a critical appraisal of the literature on laser for tendinopathy. After reviewing 5 RCT’s, they found that Laser for tendinopathy offers little clinical benefit when compared to a placebo (a sham/fake Laser).
Laser for Achilles tendinopathy:
Tumilty et al (2012) conducted a RCT comparing laser and an eccentric exercise regime to sham (fake) Laser and an eccentric exercise regime. Results at 4,12 & 52 weeks showed no additional benefit in self-report measures of Achilles function or pain.
Laser for neuropathic pain:
Andrade et al (2016) conducted a systematic review on Laser for neuropathic pain. This area of research is new and of the 15 studies reviewed, 10 were on animals. Of the 5 that were on humans, the neuropathic pain was related to diabetic neuropathy. The quality of the included studies was mixed with some of them being low quality with methodological flaws. The authors report positive improvements on pain but do not talk about the change in score or time frames (eg how much did the pain improve for and how long after treatment did it stay improved.
First, I’ll admit that my search was not extensive. I limited my reading to the last 3 years of published articles and read systematic reviews (higher level of evidence) where available, skipping individual trials (mainly as the ones I did come across had poor methodology). But, here goes:
Since laser technology has improved, the research is growing. In regards to tendinopathy, several studies with poor methodology show positive results, however, better quality studies with placebo controls are not showing the same benefits. To question the benefits further, It appears that the literature demonstrating 'limited to no benefit' is growing more rapidly than research showing benefit!
In regards to neuropathic pain, more human trials need to be conducted to better understand how dose/frequency etc may change outcomes. It's important to remember that absence of evidence is not the same as evidence of absence. This could be a very promising area if more controlled studies show improvements as neuropathic pain is very challenging to manage.
If you have tendinopathy, it's probably more cost efficient and equally as effective to start with an exercise program and skip Laser treatment. If you have neuropathic pain, it's harder to say. If you have the funds, it might be worth trying a few sessions but I'd be careful of empty promises.
Overall, the treatment appears to be safe but at an average of 12 treatment sessions for a given condition, could it be no more than a placebo and a waste of money?
Time will tell but for now, the only Lasers I'll be using are lightsabers with the kids.
Written by Roland Fletcher, Physiotherapist
Boudreault et al (2016). The efficacy of laser therapy for rotator cuff tendinopathy: A systematic review and meta-anaylisis. Journal of novel physiotherapy and physical rehabilitation. 3(1).
Doyle et al (2016). The effects of low level laser therapy on pain associated with tendinopathy. A critically appraised topic. Journal of Sports Rehabilitation. 25(1).
Tumilty et al (2012). Clinical effectiveness of low level laser therapy as an adjunct to eccentric exercise for the treatment of Achilles tendinopathy. A RCT. Archives of Physical Medicine and Rehabilitation. 93(5).
Andrade et al (2016). Use of low level laser to control neuropathic pain. A systematic review. Journal of photochemistry and photobiology, B Biology. 164.