PainScience.com Sensible advice for aches, pains & injuries
 
 

Foot “scanning” is mostly a gimmick.

Orthotics Review

A consumer’s guide to the science and controversies of orthotics, special shoes, and other allegedly corrective foot devices

updated (first published 2002)
by Paul Ingraham, Vancouver, Canadabio
I am a science writer and a former Registered Massage Therapist with a decade of experience treating tough pain cases. I was the Assistant Editor of ScienceBasedMedicine.org for several years. I’ve written hundreds of articles and several books, and I’m known for readable but heavily referenced analysis, with a touch of sass. I am a runner and ultimate player. • more about memore about PainScience.com

Readers often tell me that they think they “might need orthotics,” but they rarely know more than that. The idea is based on an uncertain hunch that something about the way they walk and run can be fixed with a wedge of just the right shape under their feet — which is all orthoses amount to, even the fanciest ones.

Custom foot orthoses or orthopedic footwear or modifications can be really helpful … but mostly for specific, technical, and medical reasons.1 Meanwhile, there are many unscrupulous and shoddy suppliers of these products who will prescribe them for almost any problem — or none! — and the science is complex and incomplete. It is nearly impossible for consumers to know if they actually need any of these products, or where to get an expert prescription and a quality product.

The good news is that there are some more reliable sources for these products and services: Certified Pedorthists (C.Ped) and Certified Orthotists (CO) are the professionals that I recommend. Unfortunately, most consumers have never heard of them and don’t know why they are the best choices, or where to find them… and many therapists won’t refer, because they want to sell you orthotics themselves.

The entire question of orthotics can be answered reasonably well by keeping your expectations pretty low — there’s just only so much that foot support can do for most people — and by consulting mainly pedorthists and orthotists. That’s the short story. But on this website we delve into these things …

We train for many years and we take our jobs very seriously. It’s great to see support for pedorthists, and recognition of the difference between podiatrists and pedorthists. I have a problem with a professional who is allowed to diagnose, prescribe, and dispense within a 15-minute appointment. Prescribers are not providers for a reason!

— T.Moffitt, C.Ped. (C)  Certified Pedorthist, Edmonton, Canada

Caveat emptor! Many orthotics are poorly made and for the wrong reasons

Foot, ankle, knee and hip biomechanics are complex. Extremely complex. It’s not rocket science — it’s actually much harder. And gait analysis is an art as well as a science. In my opinion, non-specialists just cannot possibly navigate this maze successfully with every patient. Orthotics should not be prescribed without a thorough examination — at least a half hour, and more if the case is complex.

Yet across North America — and I’ve seen it myself here in Vancouver — you can find lab-coated charlatans hawking corrective shoe inserts in shopping malls, using flashy displays and entertaining technology to “assess” or “scan” your feet with lasers or infravision … anything at all that will distract you from their lack of skill and real knowledge.

Unfortunately, many orthotics sold to consumers may not be worth more the clay the mold was made from. The effectiveness of orthotics is uncertain no matter who prescribes them, which I’ll get into below. Most “custom” orthotics are mostly just pieces of plastic that fit your foot. Maybe. None of the common methods can even create an accurate fit reliably! Pedorthists and orthotists have the best chance of providing a useful prescription. Only pedorthists are trained in both gait analysis, lower body anatomy and biomechanics and the actual fabrication of custom foot orthoses.2 All other professionals are obliged to order orthotics from an external supplier.

Most physical therapists or chiropractors selling orthotics usually ask a client to make footprints in foam in a box, fill out a form specifying features of the insert, and then ship the foam off to a manufacturer who sends back some shoe inserts. Like lasers at the mall, these procedures may create the illusion of a “customized” product, but it’s mostly just a piece of plastic that fits your foot. Maybe. None of the common methods can even create an accurate fit reliably!3 Let alone one that is corrective or therapeutic in any way. Such “prescriptions” are extremely common practice, but wiser and more ethical practitioners wisely shun them. This massage therapist described to me how she refused the sales pitch:

A few years ago I had a phone call from a company that was trying to sell me a franchise to sell and fit orthotics. Apparently I could make very good money doing this. I’m a massage therapist and I think I have a better-than-average knowledge of feet and gait, but I do not consider myself qualified to fit and sell orthotics. No fear, the company representative said they would send someone to train me — for half a day! The sales person seemed to be astonished that I turned down this wonderful opportunity. I prefer to refer my clients to a person who is qualified to do this work.

Good for her. But many professionals jump at this dodgy chance to make more money.

Alas, even podiatrists (foot doctors) don’t necessarily provide good orthotics

Most consumers assume a foot doctor is a good source of orthotics. Unfortunately, this is far from guaranteed. Many podiatrists are qualified for it, but probably most are not, as suggested by this rather chilling story from Dr. Michael “America’s Podiatrist” Nirenberg:

A middle-aged woman arrived at my office last week complaining of heel pain and carrying a bag of custom-made foot orthotics (orthotics are custom made arch supports that are fabricated from a mold of the patient’s feet). Each orthotic this woman had with her was expertly fabricated by a different podiatrist and yet none of them had come close to alleviating her heel pain. At first I thought maybe these podiatrists didn’t know what they were doing. But, when I learned their names, I knew this woman had seen competent, skilled and reputable physicians.

I asked myself “how could this be?” More interestingly, no two sets of orthotics were even remotely alike. Further, given that nearly all podiatrists learn similar principles of biomechanics, shouldn’t orthotics for a given patient be the same regardless which podiatrist makes them?

Dr. Michael Nirenberg, in his review of a book by Dr. Benno Nigg, Biomechanics of Sport Shoes: The Disturbing Truth About Running Shoes, Inserts and Foot Orthotics

A podiatrist is a full physician, but specializing in foot problems. In Canada and the United States (most familiar to me), his or her expertise is primarily concerned with foot pathology and corrective surgery, and does not always extend to include expert gait analysis and physical assessment of biomechanical dysfunction of the lower limb as a whole. Obviously some podiatrists cultivate an interest in this, and there are some prominent experts in the field who have really gone this direction, but they are not obliged to do so.

You could say that it’s not in their job description.

Most podiatrists outside of North America are probably a different matter.4

In any case, even a podiatrist skilled in the prescription of custom foot orthoses is still obliged to have them manufactured by someone else. For this reason alone, many podiatrists prefer to refer their patients to certified pedorthists.

Who “needs” orthotics? Anyone?

The supply dramatically exceeds the real demand. However, there are four common conditions that orthotics have the most potential to help:

Other conditions that might be treatable — but it’s much less clear — include patellofemoral knee pain, shin splints, achilles tendinitis,5 and bunions, as well as numerous systemic pathologies that (like diabetes) affect the function of the lower limbs.

Orthotics for back pain

Back pain is extremely complex and notoriously resistant to any kind of treatment,6 probably because it is strongly influenced by many factors that we don’t understand or can’t control (like genetics, or the mind game in low back pain). In spite of this, orthotics or heels lifts are often prescribed for back pain, usually to treat a leg-length difference, which may or may not actually exist in the first place, and probably doesn’t have anything to do with the back pain.7 Back pain correlates surprisingly poorly even with the most obvious structural/degenerative issues in the spine,8 so it’s unlikely that it would be much affected by the subtler biomechanical issues that might be influenced by gait.

The evidence available on this topic — so far, such as it is, just a few small trials — suggests that insoles or foot orthoses do not prevent or treat back pain, which is hardly a surprise.9 Technically the evidence is just inadequate and inconclusive, but the absence of any benefit in the small trials done so far is damning. The only studies with positive results have obvious flaws.10

Orthotics for preventing or treating the overuse injuries of the lower body: do they make sense?

The repetitive strain injuries that runners, walkers, and hikers get are common and difficult, and they are probably the main thing that gets most people wondering if they need some orthotics. This is based on the flawed notion that RSIs are caused by flawed biomechanics.

While biomechanics may be a factor, the main problem with most repetitive strain injuries is, strangely enough, repetitive strain — that is, your body parts would likely be feeling the strain even if you were biomechanically flawless.

There can also be much more exotic factors, like the genetics of healing mechanisms, that may dwarf other factors — that is, some people will get Achilles tendinitis if they so much as go for a walk, whereas some people can run marathons for decades without any tendon trouble. These sorts of things are all explored in great detail in my free repetitive strain injury tutorial. All I want to get across here is that treating RSI is definitely not just a case of “fix those biomechanics!” It’s much harder to know if RSIs can really be treated with orthotics than you probably thought.

But it gets even worse.

Can orthotics do the job?

A lot has to fall into place before orthotics can possibly work. Even if you do have a biomechanical glitch at the heart of your RSI:

If you can’t tick off one of those, the game is up: orthotics aren’t going to work out. It all adds up to a very long shot, which is probably why evidence about the efficacy of orthotics for treating any lower limb problems has been discouraging.11 Evidence

And yet orthotics could still be worth trying — particularly if you do have a fairly obvious biomechanical problem. Good orthotics are a reasonably good way of trying to “tinker” with any gait or postural dysfunction that may have contributed to your pain in the first place. For instance, unusually high arches are a plausible factor in runner’s knee.12

My own example: orthotics that helped plantar fasciitis (but not IT band syndrome)

Orthotics certainly seemed to be a good option for me. I have an obvious biomechanical problem in my right foot.13 It’s just the sort of biomechanical bogeyman you might be tempted to blame for my own nasty history with iliotibial band syndrome. Surely that gimpy turned-out leg made me more vulnerable to IT band syndrome?

No, not as far as I’ve ever been able to tell: my own IT band syndrome was always quite symmetrical, never much better or worse on either side, with or without orthotics. And after years of being recovered, I’ve never had a recurrence of IT band syndrome, on either side.

But it was worth trying. The orthotics did help my chronic low-grade plantar fasciitis in that foot, and the experiment was fairly cheap (compared to, say, a year of chiropractic adjustments) and safe. So why not? If you have foot or leg or knee pain, by all means seek the opinion of a certified pedorthist. Even if orthotics are not likely to help, he or she may recommend a shoe type that may be more appropriate for you — a factor that is often overlooked.

Can orthotics prevent injuries?

Sadly no, probably not, and for all the same reasons that they aren’t exactly a magic treatment bullet. You should definitely be skeptical of any sales pitch for orthotics or custom shoes if you have no particular problem to solve. Many orthoses are sold with the promise that they will prevent injury. Even if prevention is not the main reason for the prescription, it is often thrown in as a bonus reason to buy. But it has been tested, with poor results.

Running and walking shoes that try to be like orthotics

More expensive running and walking shoes all try to absorb shock in various ways, and then there are also many designs intended to “correct” or compensate for common biomechanical issues like pronation … just like orthotics. Most of these designs are supposedly all about injury prevention, and this hope is behind countless gimmicky, expensive shoes with no clear benefit for consumers.14 That’s hardly surprising, because there is no clear link in the first place between running injuries and the kinds of anatomical quirks (pronation) that these shoes supposedly control.15

Running injuries are just as common as they were twenty years ago, despite all the fancy footwear, and typical “prescriptions” of running shoes — the kind you can get from an “expert” shoe seller — are definitely not evidence-based.16

These are the interesting shoes that Dr. Kerrigan’s company makes, “the first and only footwear with a midsole that provides compression and release, when and only when it should. Despite what we’ve been led to believe, no foam, plastic, air, gel, or metal ever achieved this.”

More technical, quirky shoe designs: putting a spring in your step, literally

There may still be some realistic hope for injury prevention with more specialized shoes. One of the more promising and instructive examples I know of is OESH Shoes, the creation of Dr. Casey Kerrigan, who left a promising career in biomechanics research to make shoes for women. Her goal was to simulate running on a springier surface by putting a literal spring in your step. More spring in the surface means less spring and bending in the joints.17 Hips, knees and ankles all bend less when you walk or run on a springier surface — or on springier shoes?

Mass-produced running and walking shoes claim to absorb shock in all kinds of ways, but they aren’t springy. A spring gives energy back to you: it compresses, and then forcefully expands. Most shoes are mushy: they are made of foam, and foams absorb energy but don’t give much back. Running on foam is like landing on a trampoline that does down but not up: it can’t toss you back up in the air. (There is some evidence that the mushy shock absorption of most running shoes might actually increase knee stresses,1819 though it’s not likely to be a big effect.)

Oesh shoes and other spring-loaded shoes are interesting and legitimately science-inspired. A similar spring-sole design was tested in 2017 and found to “reduce lower limb muscle forces.”20 Whether such shoes actually prevent injury is another matter entirely, and no one knows that yet. But at least it’s a good idea, which is more than we can say for an awful lot of competing products.

Shoes with springs might, conceivably, actually reduce running injuries.

For contrast, I submit exhibit B, one of the least promising examples of a special injury-preventing shoe design: minimalist running shoes, the ones that look like feet, like Vibram FiveFingers. The idea here is to remove any form of shock absorption at all and let feet do their job as nature intended, “paleo” running shoes, really just an extra layer of synthetic skin. If humans evolved to be good at distance running — and we probably did21 — why mess with a good thing? This fad has actually been studied enough in the last few years that we more or less know the answer now: it doesn’t prevent running injuries. At best it simply changes the kinds of injuries runners get, and at worst they get hurt more.22 For detailed analysis of this topic, see my article, Does barefoot running prevent injuries?

Maybe less? Not so much.

Or, read more about shock absorption and the risks of running on pavement. The short version: the evidence does suggest that it’s at least a little risky,23 but it’s not as clear as you’d think, and nothing you can put between your feet and the road has yet been proven to reduce whatever modest risks there may be.

Can orthotics cause injuries?

Orthotics are not risk-free. The risk is not large, and so not much needs to be said about it. However, good or bad, they can be difficult for a body to adjust to, disrupting fine-tuned postural adaptations and forcing awkward new ones.

I had a pair of hiking boots that I really wanted to love: beautiful, expensive boots that seemed to fit perfectly, and so sturdy. It was liking wearing cozy tanks! But they also consistently made my right foot ache about 20 minutes into every hike in a way that no other boot or shoe ever had before, or ever has since. Those hiking boots consistently made my right foot ache about 20 minutes into every hike in a way that no other boot or shoe ever had before, or ever has since. I kept those boots for years, trying them hopefully each hiking season. The pain was as as reliable as sunrise. Who can say what it was about those boots? What subtle interaction with my body? Nearly impossible to diagnose, I imagine. It was trivial but inevitable.

I’ve seen numerous examples over the years where orthotics seemed to have this kind of effect — just a temporary wrench in the works. In the worst cases, people simply ditched the orthotics and the problem was solved.

I think every pair of orthotics is a minor gamble with some potential to help … or do what those boots did.

Pedorthist shopping

To wrap up, let’s get back to the subject of pedorthists: the professionals you should seek out if you’re still wondering if you “might need orthotics.”

Certified pedorthists must have a relevant degree, spend at least three years in apprenticeship, and then pass demanding exams. That entire period of work experience is devoted to the lower limb, and to the ankle and foot in particular. There are even more advanced professional designations for pedorthists as well.

“The Pedorthic profession in Canada is moving in a great positive direction with integrity, attracting only University educated individuals to become certified pedorthists,” says Paul Rauhala of OKAPED in Canada’s Okanagan Valley. That training translates into an impressive experience for the patient: I have been a patient at OKAPED in the past, and was blown away by the thoroughness and technical expertise of their assessment, which included slow motion video. My own limited training in orthopedic assessment gave me just enough knowledge to realize how much more Mr. Rauhala knows about it than I ever will — in the leg, anyway!

C.Peds and COs are not the only sources for good orthotics, but I think they are the most likely to work out. If any other health care professional wants to sell you orthotics, please ask them to refer you to a certified pedorthist instead.

Or find one yourself! In Canada, go to the website for the Pedorthic Association of Canada. In the United States, the Board for Certification in Pedorthics. You can easily Google similar associations in other countries — wherever pedorthists are practicing, they will have an association, a website, and practitioner information.


About Paul Ingraham

Headshot of Paul Ingraham, short hair, neat beard, suit jacket.

I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.

Related Reading

What’s new in this article?

Eight updates have been logged for this article since publication (2002). All PainScience.com updates are logged to show a long term commitment to quality, accuracy, and currency. more When’s the last time you read a blog post and found a list of many changes made to that page since publication? Like good footnotes, this sets PainScience.com apart from other health websites and blogs. Although footnotes are more useful, the update logs are important. They are “fine print,” but more meaningful than most of the comments that most Internet pages waste pixels on.

I log any change to articles that might be of interest to a keen reader. Complete update logging of all noteworthy improvements to all articles started in 2016. Prior to that, I only logged major updates for the most popular and controversial articles.

See the What’s New? page for updates to all recent site updates.

MayAdded a section about spring-loaded shoes (not as lame as it sounds).

AprilAdded a section about orthotics and low back pain.

AprilScience update: cited Junior 2016 regarding the lack of link between running injuries and biomechanical asymmetries, and Richter 2011 on efficacy of orthotics for lower limb injuries.

MarchMiscellaneous improvements to the section about special/technical running and walking shoes.

2014Minor clarifications about pedorthist scope of practice.

2013Added a good quote about inconsistency in the prescription of orthotics.

2012Added valuable new reference to Telfer et al.

2012General editing and significant expansion.

2002Publication.

Notes

  1. Such as special footwear to protect diabetics from cutting off impaired circulation, or to prevent a severely degenerated joint from bending, or to help compensate for a minor deformity. BACK TO TEXT
  2. Orthotists have a more limited scope of practice and focus on the making of the orthoses themselves. BACK TO TEXT
  3. Telfer S, Gibson KS, Hennessy K, Steultjens MP, Woodburn J. Computer-aided design of customized foot orthoses: reproducibility and effect of method used to obtain foot shape. Arch Phys Med Rehabil. 2012 May;93(5):863–70. PubMed #22541310.

    Foot orthotics are made from basic measurements and captured images of the foot (plaster casting, foam box impressions, or three-dimensional computer images). None of these techniques is very accurate (<80%), especially with measuring the peak arch height. Skilled 3D computer imaging may be the most accurate. Basic measurement is particularly inaccurate.

    BACK TO TEXT
  4. I have a large international readership, so this is a worthwhile clarification! Dr. Mark Heard, in Australia, agrees with my assessment that most North American “Pods” are surgery focussed, but explains that other Pods around the world are more focussed on biomechanics:

    Undergraduate training around the world doesn’t go so far as the US in surgical training. It’s an option in other countries, but greater training is required. So most Pods here tend to be more biomechanically focussed, and more interested in a holistic approach to musculoskeletal health. We have the option of surgery, but it requires considerable post graduate training. My own training allows me to undertake superficial surgery (i.e. for ingrown toenails, removal of warts etc), but that only makes up a small amount of my practice.

    Dr. Mark Heard, Podiatrist D.App.Sci, M.A.Pod.A., from personal correspondence

    BACK TO TEXT
  5. About “tendinitis” versus “tendonitis”: Both spellings are considered acceptable these days, but the first is technically correct and more formal, while the second is an old misspelling that has only achieved respectability through popular use. The word is based on the the Latin “tendo” which has a genitive singular form of tendinis, and a combining form that is therefore tendin. (Source: Stedmans Electronic Medical Dictionary.) BACK TO TEXT
  6. Machado LA, Kamper SJ, Herbert RD, Maher CG, McAuley JH. Analgesic effects of treatments for non-specific low back pain: a meta-analysis of placebo-controlled randomized trials. Rheumatology (Oxford). 2009 May;48(5):520–7. PubMed #19109315. PainSci #54670.

    This is a meticulous, sensible, and readable analysis of the very best studies of back pain treatments that have ever been done: the greatest hits of back pain science. There is a great deal of back pain science to review, but authors Machado, Kamper, Herbert, Maher and McCauley found that shockingly little of it was worth their while: just 34 acceptable studies out of a 1031 candidates, and even among those “trial quality was highly variable.” Their conclusions are derived from only the best sort of scientific experiments: not just the gold-standard of randomized and placebo-controlled tests, but carefully choosing only the “right” kind of placebos (several kinds of placebos were grounds for disqualification, because of their known potential to skew the results). They do a good job of explaining exactly how and why they picked the studies they did, and pre-emptively defending it from a couple common concerns. The results were sad and predictable, robust evidence of absence: “The average effects of treatments … are not much greater those of placebos.”

    BACK TO TEXT
  7. Grundy PF, Roberts CJ. Does unequal leg length cause back pain? A case-control study. Lancet. 1984 Aug 4;2(8397):256–8. PubMed #6146810.

    This classic, elegant experiment found no connection between leg length and back pain. Like most of the really good science experiments, it has that MythBusters attitude: “why don’t we just check that assumption?” Researchers measured leg lengths, looking for differences in “lower limb length and other disproportion at or around the sacroiliac joints” and found no association with low back pain. “Chronic back pain is thus unlikely to be part of the short-leg syndrome.” Other studies since have backed this up, but this simple old paper remains a favourite.

    BACK TO TEXT
  8. Brinjikji W, Luetmer PH, Comstock B, et al. Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations. AJNR Am J Neuroradiol. 2015 Apr;36(4):811–6. PubMed #25430861. PainSci #53872.

    Signs of degeneration are present in high percentages of healthy people with no symptoms. “Many imaging-based degenerative features are likely part of normal aging and unassociated with pain.” And yet! See the authors’ other paper, in a later issue of the journal (Brinjikji), importantly concludes the “opposite”: that degenerative features are nevertheless “more prevalent in adults 50 years of age or younger with back pain compared with asymptomatic individuals.”

    In other words, abnormalities matter less than many patients and professionals still assume, but they still do matter.

    BACK TO TEXT
  9. Chuter V, Spink M, Searle A, Ho A. The effectiveness of shoe insoles for the prevention and treatment of low back pain: a systematic review and meta-analysis of randomised controlled trials. BMC Musculoskelet Disord. 2014 Apr;15:140. PubMed #24775807. PainSci #53612. BACK TO TEXT
  10. Cambron JA, Dexheimer JM, Duarte M, Freels S. Shoe Orthotics for the Treatment of Chronic Low Back Pain: A Randomized Controlled Trial. Arch Phys Med Rehabil. 2017 Apr. PubMed #28465224.

    This trial tested the efficacy of shoe orthotics and chiropractic treatment for chronic low back pain. 225 patients were divided into three groups: a wait-list control group got no care at all, another group received custom, and a third group got custom orthotics plus chiropractic and massage treatment. The authors reported positive results up: “Six weeks of prescription shoe orthotics significantly improved back pain and dysfunction compared to no treatment.” But no differences after 12 weeks! And that’s even with an unfair advantage…

    Wait-list groups are a crappy control. They suffer from “frustrebo” — poor outcomes caused by disappointment of knowing that you are not getting any treatment (see Power). This is a major flaw. As Dr. Stephen Ward tweeted, “Waiting list control, schwaiting list control.

    The lack of a true placebo control is a deal-breaker here, especially put in the context of other studies of orthotics for back pain, which are negative (e.g. see Chuter). Without replication, I think this study’s results can be dismissed as an outlier attributable to a flawed design and a high risk of bias.

    BACK TO TEXT
  11. Richter RR, Austin TM, Reinking MF. Foot orthoses in lower limb overuse conditions: a systematic review and meta-analysis--critical appraisal and commentary. J Athl Train. 2011;46(1):103–6. PubMed #21214358. PainSci #53613.

    A review of studies of foot orthoses to treat overuse injuries of the lower limb with a mostly negative conclusion: “no difference between custom and prefabricated foot orthoses” and “the evidence was insufficient to recommend foot orthoses (custom or prefabricated).” (One thin ray of light was that the evidence supposedly supports the use of foot orthoses to prevent a first injury… but, even if true, hardly anyone seeks out orthoses before they develop an overuse injury. And why would they be good only for a first injury? Makes no sense, therefore likely not true.)

    BACK TO TEXT
  12. McKenzie DC, Clement DB, Taunton JE. Running shoes, orthotics, and injuries. Sports Med. 1985;2(5):334–347. BACK TO TEXT
  13. It’s a “forefoot varus,” meaning that the front of the foot is twisted away from the midline. It’s minor and subtle, but unambiguous. As soon as I could walk, I did so with my right foot turned out. The first time my parents took me cross-country skiing, when I was just a tiny lad about four years old, I had trouble keeping my right ski in the track! It just kept popping out. BACK TO TEXT
  14. Runnersworld.com [Internet]. Burfoot A. Veteran Biomechanics Expert Benno Nigg Doubts That Barefootin', Forefootin' Or Pronation-Control Will Change Injury Rates; 2011 Jun 1 [cited 14 Jan 1].

    Terrific short myth-busting interview with a running, shoe and biomechanics expert — who is (delightfully) a bit cranky about “so many wrong ideas out there.” It’s all too rare to see this kind of sanity-inducing, hype-reducing talk on this topic.

    From the article, regarding the position of biomechanics expert Benno Nigg:
    Nigg has noted that running injuries have not changed over the years despite the massive development of the running-shoe industry. Unlike others, he hasn't jumped to the conclusion that shoes are bad, or that barefoot or minimalist-running or forefoot-striking is the answer. Instead, looking at the same data, Nigg concludes: Okay, apparently shoes aren’t a big part of the equation.
    BACK TO TEXT
  15. Hespanhol Junior LC, De Carvalho AC, Costa LO, Lopes AD. Lower limb alignment characteristics are not associated with running injuries in runners: Prospective cohort study. Eur J Sport Sci. 2016 Jun:1–8. PubMed #27312709.

    Do runners with anatomical quirks get more injuries than symmetrical and aligned runners? This study was another attempt to settle an old question that just won’t die.

    It was the right kind of study (prospective), but perhaps a bit underpowered with only 89 subjects and just 12 weeks of monitoring for new injuries. I wish I could see the same data for a couple hundred runners over six months. Subtle vulnerabilities might take quite a while to crop up, particularly in runners who have already gotten through at least six months without any injury. Still, 24 of these runners did get injured in those twelve weeks — which is a lot! — and “we did not find significant associations between lower limb length discrepancy, Q-angle, subtalar angle and plantar arch index and injury occurrence.”

    Surprise surprise. And so, as we’ve known for years, either’s there’s no relationship between running injuries and anatomical imperfections at all… or it’s too subtle to detect easily, in which case who really cares? These things are mostly impossible to fix anyway.

    BACK TO TEXT
  16. Richards CE, Magin PJ, Callister R. Is your prescription of distance running shoes evidence-based? Br J Sports Med. 2009 Mar;43(3):159–62. PubMed #18424485. BACK TO TEXT
  17. Humans have a couple main biological shock absorption tricks: one is to dampen vibrations with precisely timed muscles contractions (which is very cool, see Boyer 2004), and the other is to bend like a complex spring (Ferris 1997). The springing is really obvious in an extreme example, like bouncing on a trampoline, where you can keep your knees straight; but jump down just one metre onto concrete, and you’ll have bend your knees quite a lot. We do the same thing much more subtly when we walk and run. We’re amazing at making much finer, faster adjustments to surface rigidity when running (see Ferris 1999). BACK TO TEXT
  18. Kerrigan DC, Franz JR, Keenan GS, et al. The effect of running shoes on lower extremity joint torques. PM R. 2009 Dec;1(12):1058–63. PubMed #20006314. PainSci #55087.

    As measured in this study, wearing modern-day running shoes designed for stability caused “relatively greater pressures at anatomical sites that are typically more prone to knee osteoarthritis.” The authors acknowledge that it’s hard to know what to make of this, and there are many other potentially relevant variables.

    BACK TO TEXT
  19. Keenan GS, Franz JR, Dicharry J, Della Croce U, Kerrigan DC. Lower limb joint kinetics in walking: the role of industry recommended footwear. Gait & Posture. 2011 Mar;33(3):350–5. PubMed #21251835.

    Do running shoes have positive or negative impacts on joints? Researchers analyzed peak joint forces in barefoot walking versus three different types of shoes: stability, motion control, and cushion. Results showed an increase in knee and hip flexion forces in all shod conditions during the early stance phase, mostly due to increased step length. This is not clear evidence that “shoes are bad” — more forces are not necessarily bad — but it is an interesting addition to the debate about the biomechanics of shoes versus going barefoot.

    BACK TO TEXT
  20. Wunsch T, Alexander N, Kröll J, Stöggl T, Schwameder H. Effects of a leaf spring structured midsole on joint mechanics and lower limb muscle forces in running. PLoS One. 2017;12(2):e0172287. PubMed #28234946. PainSci #53523. BACK TO TEXT
  21. Bramble DM, Lieberman DE. Endurance running and the evolution of Homo. Nature. 2004 Nov;432(7015):345–52. PubMed #15549097. BACK TO TEXT
  22. Altman AR, Davis IS. Prospective comparison of running injuries between shod and barefoot runners. Br J Sports Med. 2016 Apr;50(8):476–80. PubMed #26130697.

    I waited a long time for this one: at last, the first prospective comparison of injury rates in shod versus barefoot running. All research on this topic until now has been unable by design (methodologically inadequate) to answer this question, and so for many years now we’ve endured tedious argument about injury rates based on the wrong kind of data. “Prospective” is what we needed the whole time: following a bunch of initially uninjured runners of both types to see what happens to them.

    For this test, 200 experienced runners were studied over the course of a year: 94 wearing shoes, 107 with no shoes or (for about a quarter of their mileage) “true minimalist shoes.” The barefooters had been running that way for at least six months, and more than 18 on average, so they weren’t in that awkward transition phase where injury rates could well be higher.

    The results are clear and unsurprising: there was no important difference in injury rates, just the kinds of types of injuries. Each is better in some ways, worse in others. Although the paper emphasizes “fewer overall injuries” for barefoot runners, injury rates are what matters — the number of injuries per 1,000 miles, say — and they were “not statistically different between groups due to significantly less mileage run in the barefoot group.”

    But there’s an extremely important caveat, and it does not flatter barefoot running: the barefoot running volume was just 24 kilometres a week, while runners in shoes ran nearly twice as much — 41km — without an increase in injury rate. Although this is all made clear in the paper, it’s strange that it wasn’t more strongly emphasized. As Alex Hutchinson put it for Runner’s World, “The only way the comparison has any relevance is if they’re arguing that barefoot running reduces injuries by preventing you from running as much as you’d like.”

    Naturally, a larger, longer study may have different results. But this is an excellent start, and we can now say with high confidence that barefoot running is not a panacea for running injuries.

    BACK TO TEXT
  23. There’s a lot of research about impact, some of it concerning different surfaces, just a few of those specifically about the relationship between impact and injury. As of the end of 2016, there were only about 18 decent experiments, with too many differences between them to clearly interpret. A review of these by van der Worp et al concluded just a single specific link (stress fractures); otherwise they reported only a broad association between higher loading rates and runners with all kinds of injuries (but none in particular). Davis et al found that “all impact-related variables were higher” in 250 women runners who got injured in a year after extensive gait analysis. And the best evidence so far on barefoot running, from Altman et al, clearly shows that running without padding (barefoot) is problematic.

    So while it’s not as obvious or simple as you’d think, the science does suggest some risk. I’ve shared just the tip of the science iceberg here, and there’s a whole article dedicated to the rest: Is Running on Pavement Risky?

    BACK TO TEXT