The Problem with the Treatment of Plantar Fasciitis

Probably a day does not go by in which I read something somewhere about plantar fasciitis and I end up face palming myself and eye rolling. The worst are those that usually start with “The Truth About…“; that usually gets a double face palm that hurts me and the eyes rolling so far that I almost see my brains! There is so much snake oil and junk being advocated for its management.

The problem with trying to manage plantar fasciitis is that it always gets better on its own….eventually. Just look at all the clinical trials on plantar fasciitis: the placebo, control groups or non-treatment groups almost always improve. This suggests that the natural history of plantar fasciitis is to improve without treatment eventually. Now this “eventually” may be years in some people and over the short term in other people. As plantar fasciitis hurts, this does not mean that it should not be treated; it should. What it means is it needs to be treated with interventions that have a greater success rate than what would occur naturally if it was left alone.

If I was to take 100 people with plantar fasciitis and do nothing and come back in a month, then X% will be better just due to the natural history alone. If I was to give these 100 people some snake oil or equally useless treatment and check them in a month, the X% will be better. Of course those X% are going to be totally convinced that the snake oil fixed them no matter what I say. They will then get into social media to become advocates of that snake oil and promote that snake oil as working, when in reality it worked no better than what would have happened with the natural history of the condition. There is going to be some serious trolling and anger going to go on in social media and hate mail if you try and point this out to them. I have previously written about why ineffective treatments sometimes appear to work. This is how and why the plantar fasciitis snake oil salespersons can claim some success and produce testimonials; it is just that their success is no better than what would have happened naturally if nothing was done. Dubious products remain on the market to fleece the unsuspecting.

The challenge with managing plantar fasciitis (and almost every other condition) is situations like that. Was it the treatment that was used or was it the natural history? Was the plantar fasciitis about to get better on its own or was it the treatment? That is why proper clinical trials of different treatment options are so important. We want to take that 100 and then randomize them either to a treatment and to a placebo. X% in each group is going to be better after a month. If the treatment is effective, then there will be more in the treatment group that are betterer than in the placebo group (and a statistical test will be done to show the significance and effect size of that difference).

If you hang out in some of the patient support groups for plantar fasciitis you get an interesting perspective. I see treatments being advocated all the time, yet they have no physiological or mechanical reason as to why they would ever work. There is always a few anecdotes and testimonials backing them up, often quite assertively. Sometimes you do see someone post that they tried X but it did not work for them. Even here on my blog I had one runner somewhat aggressively comment that his Hoka’s caused his plantar fasciitis and the very next post was from another runner who swore ‘black and blue’ that his Hoka’s cured their plantar fasciitis! How useful are those kinds of anecdotes and testimonials to clinicians trying to make clinical decisions and recommend the most effective treatment? It could well be that Hoka’s are more effective than placebos or the natural history for plantar fasciitis and that one runner who is claiming that it caused his is maybe putting people off what might be an effective treatment. Alternatively, Hoka’s might increase the risk for plantar fasciitis and that one runner who claims it cured his and advocating there use for plantar fasciitis may be making people worse. Hopefully you can see that anecdotes and testimonials, while important to the individual making them, they are not much use in the clinical decision making process. I am sure you can imagine the consequences of arguing this in social media when people beleive that X helped or hurt them when it may well have been just the natural history of the condition getting worse or getting better about the same time that they did X. These kinds of discussions inevitably end up in a bad place as people do give a lot of weight to their personal experiences and to anecdotes.

So what is a clinician to do? Whose and what advice should those with plantar fasciitis follow? The answer is to use those treatments that have been shown in proper, well controlled and correctly analyzed clinical trials that the treatment is better than no treatment (ie is betterer than the natural history). I tried to address those issues in my post on: Plantar Fasciitis – how then do you treat it?

To further complicate all this, the natural history of plantar fasciitis is not linear, it is cyclical. This means that over time the symptoms go up and down naturally. When an effective treatment is used just as there is an up-swing in symptoms, then that treatment will be dismissed as ineffective (the symptoms may have been worser if the treatment wasn’t used). If an ineffective treatment is used just as the symptoms are on a down-swing naturally, then that treatment is going to be hailed as a miracle! Try arguing this in social media with those who experienced it.

Not all plantar fasciitis is plantar fasciitis!
I not really talking about the differential diagnosis of plantar fasciitis, but there are probably a number of different clinical sub-groups of plantar fasciitis that will respond differently to different treatments:

Firstly there is the -itis (inflammation) versus -osis (degeneration). Fasciitis is the name that has stuck with this condition, but the vast majority are not really -itis (inflammation), except possibly in the very early stages. Most are actually a -osis (degeneration), hence the preference for some to refer to it as plantar fasciosis or plantar fasciopathy. The significance is that some interventions work for -itis and don’t work for -osis and vice versa. So an effective treatment may fail if the pathophysiology is predominantly -osis and the treatment is directed at the -itis. For example, I have come across some dietary recommendations for plantar fasciitis, but the recommendations were really just claimed to address the -itis (and had no clinical trial data that going on that diet was any better than the natural history). Tough luck if the predominant pathophysiology is -osis.

Secondly there is the thickness of the plantar fascia which could be used to put cases into different subgroups. A mildly thicker plantar fascia is probably going to be more responsive to most treatments than a very thickened one. The most thick ones might not respond to any treatment other than surgery, so in those cases effective treatments are possibly going to fail. Maybe 20%-25%-30%-50% of the mildly thick one comes right in a month due to the natural history, so an incompetent clinician or snake oil peddlar can still claim a good success rate if they predominately deal with that subgroup.

Thirdly there is the hypoechoic signal (the amount of blackness on a diagnostic ultrasound) that can also be used to put cases into subgroups. While I have no data on this, I do get an impression that this might become an important prognostic indicator in the future of how plantar fasciitis will respond to different treatments. A number of clinicians whose competence and experience I respect have started relating their clinical experiences with this. Those with a mild hypoechoic signal might be more responsive to some interventions than those with a more pronounced hypoechoic signal which might only respond to more aggressive interventions such as shockwave and surgery.

Using duration, thickness and the extent of the hypoechoic signal could potentially subgroup those with plantar fasciitis and help predict which treatments are likely to be more effective. This further complicates the issues I raised above re the natural history. This subgrouping could also further complicate clinical trials. For example what if I recruited people with plantar fasciitis into a clinical trial for a particular treatment, but by chance (maybe because of the source of the people recruited) most of them had a thicker plantar fascia with a more severe hypoechoic signal, then I may demonstrate that the treatment was no better than the natural history in that cohort. Alternatively, if by chance most of them only had a mild thickening of the plantar fascia and the hypoechoic signal was only mild – this probably means that the treatment I am testing does much better than the natural history (or it might not if it is an ineffective treatment).

Not all treatments work all the time
To further complicate the above, effective treatments do not work all the time. Its just not plantar fasciitis. Knee replacement surgery does not work all the time for severe knee osteoarthritis. Antibiotics for a strep throat do not work all the time. Surgical repairs of hernia do not work all the time. That is despite that the clinical trails showing they are better than a placebo or the natural history and those treatments are probably the best options for those conditions. All effective treatments for pretty much everything have a 5-10-15-20% failure rate. The treatments for plantar fasciitis are no different. Just because a treatment that has been shown in a clinical trial to be better than a placebo or the natural history and does not work for a particular individual does not mean that the treatment is ineffective. These people can become quite vocal in social media and other circles coming out advocating against that treatment. How many people do not get an effective treatment because of this? Imagine what happens in social media conversations when you try and point out the above issues – they tend to not end up in a good place.

The management of plantar fasciitis is not that difficult, but it is complicated by the above issues. “Plantar fasciitis” in the above could easily be replaced by almost any conditions. The issues are the same (I just used plantar fasciitis here as I know more about that). For me as a clinician, the whole management of patients now takes place in the context of the social media milieu and with the much wider availability of individual experiences mixed with both good and bad information. This points to the even greater need to rely on the research. For me as a researcher (or consumer of research), I need more information from the trials, especially the issues surrounding the sub-grouping mentioned above.

As always, I go where the evidence takes me until convinced otherwise. … and please let there be properly conducted, controlled and analyzed clinical trials on the right subgroup before you start selling the $19.95 eBook that you have found the cure or plantar fasciitis.

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13 Responses to The Problem with the Treatment of Plantar Fasciitis

  1. John March 23, 2016 at 6:43 am #

    “The problem with trying to manage plantar fasciitis is that it always gets better on its own….eventually.” Exactly. This has been my limited experience as well…

  2. Martin April 7, 2016 at 6:50 am #

    Good rant Craig. I concur with your thoughts on the potential value of using a sonographicaly derived classification as a basis for treatment stratification. As you know this has been used but there is no science yet to my knowledge to support it. Based on our own experience it I think it would be difficult to design a study which could confidently control for therapeutic compliance. I believe that is a major confounding factor in measuring conservative therapeutic outcomes for MSK health. Cheers Martin

  3. Jo April 15, 2016 at 12:12 pm #

    Thanks for this! I’m an injured marathon runner with a suspected plantar fascia tear and I’ve been desperately scouring the internet for anything resembling compelling evidence on effective treatments and recovery time – it’s a desert out there! To your knowledge, is there a big difference between treatment for a traumatic tear and what works for chronic plantar fasciitis? For the time being I’ve been resting, icing and applying anti-inflammatory cream topically. Best, Jo

    • Craig Payne April 15, 2016 at 6:29 pm #

      With a partial tear, there is not a lot more than what you are doing and time; then a gradual loading program and gradual return to full activity.

  4. Paul April 26, 2016 at 4:21 am #

    A large Podiatry group in Brisbane proudly claim a 98% success rate in resolving Plantar Fasciitis using milled EVA orthotics:

    I wish we could all hope for such results

    • Craig Payne April 26, 2016 at 4:25 am #

      Extraordinary claims needs extraordinary evidence.

  5. Kevin Morgan May 18, 2016 at 12:06 pm #

    Great post:
    So many claims, so little proof!
    I’m a runner (triathlete), been studying plantar fasciitis for several years. I’m NOT trying to sell you my books. I’m more interested in guest posts. I read horror stories all the time, and even did some research using them, collecting the data from Facebook.
    The trick is to find the underlying cause (for me, case 1, overtraining, case 2, sub-luxated pelvis from a bike wreck).
    I talk about my ideas on my site (Athlete with Stent), and if you’re interested in writing a guest post, or getting one from me, let me know.
    It’s all in how people move. The doctors injecting cortisone drives me nuts – the pain is coming from somewhere else (nociception).
    I did like your article, nothing works for everyone all the time, that’s for sure. Each case is different.
    Here’s my page: if your interested in spreading commonsense about it:
    Happy Trails,,
    Kevin aka FitOldDog

    • Craig Payne May 19, 2016 at 2:11 am #

      There are several good well designed RCT’s that show cortisone shots are better than placebo or the natural history. So why would they not be used?

      • Kevin Morgan June 27, 2016 at 11:26 pm #

        Me again!
        Was walking along, and thought:
        “Cortisone injections in the heel make no more sense than injecting the lateral knee for ITBS, or the left arm for angina pectoris:
        So, why does it help, sometimes, to stick cortisone into the heel (or the patient’s platelets or blood, by the way)? It surely affects biomechanics – it would mine!! Pregnancy has caused and fixed it. Barefoot running, the same!
        I opt for nociception, spinal warning reflex, especially as I could induce it in a few minutes by sitting on my hamstrings, and get rid of it even quicker by stretching them, when I stood up – that was my second case, classic, intense, stabbing heel pain.
        OK! I’m going on a bit.
        Back to something else, and hopefully I can get my running back on track, in time for Louisville IM.

  6. Kevin Morgan June 1, 2016 at 5:19 pm #

    HI folks,
    I’m back with a request for people to consider filling out a simple, and confidential plantar fasciitis research survey. It is generating valuable information on treatment effectiveness.
    The more data, the sooner we’ll fix this progressive, and painful, disease.
    Here’s the link to the survey.
    All help very much appreciated.
    kevin aka FitOldDog

  7. Christina August 16, 2016 at 2:10 am #

    It’s been 13 years and I am sitting here icing my feet, I find it very hard to believe that PF “gets better on its own.”

    • Craig Payne August 16, 2016 at 4:16 am #

      Yep; just look at the control group in the studies on plantar fasciitis – they always improve.
      If you have had it for that long, then it has been mis-managed or mis-diagnosed.

  8. Gareth April 16, 2018 at 11:26 am #

    Probably the best 101 on PF out there…

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