Category Archives: Snake Oil

Cannabis Oil for Plantar Fasciitis

There seems to be increasing advocacy for the use of cannabis oil (medical marijuana) for plantar fasciitis recently, mostly from what I can see, from those who sell it. If you hang out in some of the online communities for those with plantar fasciitis, you see a lot of very bad advice being given, mostly based on anecdotes. In the last year or so, the most popular advice was to use magnesium supplements to cure plantar fasciitis. This was all the rage for a while with an extraordinary number of people advocating its use based on it working for them (when we have no idea if it actually worked or not or if it was just a placebo or just part of the natural history or any other explanation). There is no mechanism that I could find by which it could affect plantar fasciitis. More recently, the volume of advice for the magnesium supplements has started to drop off but is being replaced with an increasing amount of advice for the use of cannabis oil to treat plantar fasciitis. Some of the testimonials are quite compelling … if they are true.

Cannabis oil for Plantar Fasciitis

I have not paid much attention to the medical uses of cannabis oil or marijuana and the evidence for that use. I do watch and read the news stories about how it should be legalized. Those news stories almost always tell a compelling story of someone who is sadly very ill and not much available to help them, but the cannabis oil did miraculous things for them. Many jurisdictions are starting to legalize it and the commercial legal sales of the product are proving quite lucrative. Personally, I have a neutral opinion on if it should be legal or not. I see the superficial arguments in news stories that it should be and see the equally superficial arguments of the dangers of it. Sound bites for the news do not lend themselves to deeper analysis, but unfortunately, play a big role in informing public opinion and inspiring politicians to act.

Given all the attention that it was getting, the strength of the arguments to legalize it and politicians who are passing laws to legalize it, I assumed that there must be some pretty good evidence supporting its use in a number of medical conditions. After all, politicians would not be legalizing it unless there is good evidence it that it helps … wouldn’t they? 😉 ?

When I started to see the advice come up to use it for plantar fasciitis, I thought I would do a hunt for the actual evidence for its use to treat different medical problems. After all, there would have to be some evidence that it cures cancer as why would there be so many claims that it did. Surely, people would not make shit up about it wouldn’t they? 😉 ?

I was genuinely quite shocked to find just how little evidence there is for the medical use of cannabis oil or marijuana to treat anything. It certainly does not cure cancer. There is a summary of the systematic reviews and meta-analyses on it at the Science-Based Medicine blog from Steve Novella (link). Yes, there are some good early results in a very limited range of medical conditions. It is very clear, however, that the claims for the benefits massively outstrip the evidence for those claims. I really was quite surprised at the lack of evidence to support its medical use (and I know I am probably going to get anecdotes in the comments below about how it worked or me … blah, blah, blah. Please do not waste your time posting a comment about that as it won’t be approved. Suggest you read this instead: But, but … it worked for me).

Back to its use for plantar fasciitis. There is no evidence that it helps (anecdotes are not evidence). There is no pathophysiological mechanism by which it could help. Plantar fasciitis is a mechanical problem. Pharmacological interventions (eg cannabis oil) do not help mechanical problems and only may mask the symptoms (which is not always necessarily a bad thing). The only way that cannabis oil could help plantar fasciitis is by helping those with a chronic pain problem feel better about themselves. It is not a treatment for plantar fasciitis.

One irony in all this is that those who are mostly advocating the use of cannabis oil, tend to be those into “natural” therapies (another bogus claim to be addressed another time) and tend to advance the argument that the “medical establishment” do not know how to treat the root cause of problems (another bogus claim to be addressed another time) who just use drugs to mask the real problem (another bogus claim to be addressed another time). Is that not exactly what they are doing in advocating cannabis oil for plantar fasciitis?

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Reflexology research …. ‘low hanging fruit’

When you are busy and have so much important stuff to write about, it is so much easier to go after the ‘low hanging fruit’. Much less effort is needed and when it so easy, you don’t need to think too hard about it. Research on reflexology never fails to deliver on that count.

Reflexology is total bunk; it is made up pseudoscientific bullshit that has no basis what-so-ever. There is absolutely no known physiological mechanism linking areas on the foot to different organ systems and not one clinical trial that stacks up to scrutiny shows that it works. Every single clinical trial on it either shows it does not work or if it shows it works, it has fatal flaws in the methodology (and as such should never have been published, let alone carried out) or more often than not, was not even a clinical trial on reflexology, but a clinical trial on a damn good foot massage. Almost everyone is going to feel better after a damn good foot massage, so measures of anxiety etc are going to improve, especially if a chronic illness is present. Being more relaxed after a damn good foot massage is going to affect a number of psychosocial factors as well as some physiological parameters. BUT, that is not evidence for the junk that is reflexology, that is evidence for a damn good foot massage.

I previously blogged about how randomized trials on reflexology almost always end up with the exact same number in each group, which is really hard to do if you randomize properly. That is just symptomatic of the methodology issues that affect clinical trials that are allegedly done on reflexology.

What brought this on today was this study on “reflexology” and EEG testing of cortical oscillatory waves in the brain. The research measured a whole lot of parameters in the brain before and after a massage stimulation of the point on the foot (plantar hallux) that reflexologists claim is linked to the brain. They found changes.

BUT, there was no ‘control’ or ‘placebo’ massage stimulation of any other areas of the foot, nor a separate control group. So we have no way of knowing if the massage stimulation was just that or if it was due to stimulation of the specific area that they claimed is linked to the brain.

And even if they did that, they did not find what they claim they found. The analysis consisted of multiple comparisons which means they need to do a Bonferroni adjustment to an acceptable p-value. This means none of their results were actually statistically significant like they claimed, so they found nothing and certainly did not found what they claimed they found.

Another reflexology paper to consign to the trash heap.

Even more embarrassingly for the authors and the journal is this picture and what they labeled the dorsum of the foot:

oh dear. See why research like this is such a ‘low hanging fruit’: so easy to go after, so easy to debunk and so easy to write. Next.

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