Are Orthoses Effective For Heel Pain?

While there is not overwhelming support in the literature for the use of custom orthoses for heel pain, this author points to the lack of key details about prescription elements for the orthoses or patient foot types in these studies, and offers recommendations to improve outcomes with orthoses in clinical practice.

The foot orthosis industry is a $3.2 billion market globally.¹ This includes both over-the-counter devices and custom orthoses. Despite this fact, there are people and practitioners who insist that orthoses do not work for heel pain or anything else.

I have heard the terms “magic shovels” and “biomagic” used many times when referring to foot orthoses and for foot and ankle biomechanics. I have never really understood whether those who use these terms really think there is no scientific evidence to support the use of orthoses or if it is just a defense mechanism to cover for a shortcoming in their education or understanding of how orthoses and foot and ankle biomechanics really work.

Those of you who know me or of me know I am a big user, supporter and at times educator on the use of foot and ankle biomechanics and orthoses. In regard to whether foot orthoses work for heel pain, I would like to offer my perspective on why the literature does not show outstanding outcomes in support of foot orthoses and then discuss why I think “we” as practitioners fail to take full advantage of what a truly customized foot orthosis prescription is and can potentially do to help our patients.

A Closer Look At The Mixed Literature On Orthoses For Heel Pain

Several studies show that orthoses do work to some extent for heel pain but these studies don’t really show the overwhelming response that most of us regularly see when we treat patients day in and out for heel pain disorders.^2–5

This year, the British Journal of Sports Medicine released two papers within eight months of each other that had contradictory results on whether foot orthoses work for plantar heel pain.^2,3 The first study, a meta-analysis by Rasenberg and colleagues, looked at pooled data from six studies.² The authors concluded there was no difference between prefabricated, sham or custom orthoses for heel pain for up to three months. They concluded by stating, “Foot orthoses are not superior for improving pain and function compared with sham or other conservative treatment in patients with (plantar heel pain).”

Another study by Whittaker and coworkers found there was minimal evidence for short-term success of treatment with orthoses.³ However, the authors found that “in the medium term there was moderate quality evidence that foot orthoses were more effective than sham foot orthoses at reducing pain.” They still found no difference between customized or prefabricated foot orthoses for any length of time studied.

Two other studies found little to no difference between the use of prefabricated devices and customized devices for heel pain.^4,5 Specifically, Landorf and colleagues conducted a randomized trial of 135 patients with plantar fasciitis, who received either a sham orthosis, a prefab orthosis or a custom orthotic.⁴ The authors noted that although orthotics facilitate small short-term functional benefits in function and potential improvements in pain, orthoses do not have long-term beneficial effects in comparison with sham devices. In a review of five trials of 691 patients with plantar fasciitis, Hawke and coworkers note it was unclear if custom-made orthoses were effective.⁵

As you can see, these studies are not exactly overwhelming in support of the use of custom foot orthoses in the treatment for heel pain. The studies don’t say orthotics do not work for the most part but the studies do say orthotics don’t seem to be any better than any other type of treatment or an over-the-counter or sham device at the very least.

Where The Literature On Orthoses For Heel Pain Is Lacking

The issue that I and others have regularly taken with these and other studies (whether they are individual studies or meta-analyses) on orthoses is that there are rarely, if ever, any prescription elements mentioned in the orthoses the researchers used or evaluated in these studies. This goes both for OTC devices and customized or truly custom orthoses. Further, there are rarely any discussions, beyond foot or arch type, regarding the participants’ individual biomechanical variables in the studies. I have always found it helps if you have some idea of what the biomechanical elements are of the feet you are about to treat before you prescribe patients an orthosis. In general, I would think most other practitioners would agree.

My friend Craig Payne, DPM, who runs Podiatry Arena and has great online educational bootcamp courses, has written in a blog post about the “dose response” issue when researchers study orthoses.⁶ He cites as an example that any normal drug study in the medical literature would surely fail or show mediocre results at best if one used the dosage of the tested medication at only one-half or one-quarter of the expected usual dosage. Dr. Payne’s point is (and I fully agree) that most studies on orthoses are with OTC or neutral casted orthoses with no actual prescription. In other words, there are no postings, no heel lifts, no cutouts, etc.

Dr. Payne and I have also talked for several years about how there are rarely any actual data listed on what foot types the patients in the studies had or even basic Foot Posture Index (FPI) measures they may have.⁷

I am no fan of the FPI because I do not feel it offers any advice on what exact prescriptive elements to add into an orthosis. I think this is something that is lacking in our biomechanics world. Root took us a long way in our understanding of foot structure and function, but despite that, most custom orthosis prescriptions are for 4 degrees of forefoot and rearfoot posting with either intrinsic or extrinsic posting.⁸ That is hardly something any of us should be doing on every patient with heel pain who walks through our doors.

Other Pertinent Considerations

Not all patients with heel pain have pronation on stance. I know this because I compare the neutral calcaneal stance position (NCSP) to the resting calcaneal stance position (RCSP). What about ankle joint equinus or lack of dorsiflexion range of motion at the ankle joint? When people raise their hands at educational lectures on biomechanics when asked who regularly uses some sort of heel lift, unilaterally or bilaterally, on their foot orthoses, it is rarely ever more than 10 to 15 percent of the audience. If we cannot stretch away ankle equinus, then we must address equinus some other way and adding heel lifts to an orthosis can address that.^9,10

What about limb length difference?¹¹ When I speak at conferences and ask who checks for limb length difference on their patients, fewer than 10 percent of audiences will raise their hands. Much of the limb length discrepancy that is out there is functional. By that, I mean that if you correct for the subtalar joint, pronation and ankle joint limitation in range of motion (ROM), a functional limb length discrepancy will usually go away with a proper orthotic prescription. However, if you don’t even look for limb length difference in the first place, then how can you even say it is or is not a factor in the patient’s heel pain, let alone attempt to treat it?

I regularly utilize forefoot valgus posts to relax the plantar fascia in my orthotic devices.¹² Testing the lateral column excursion can help you to determine whether this is necessary or not. I know many practitioners will tell you they maximally pronate the lateral column when casting and plantarflex the first ray at the same time. I used to do this myself. The problem with this technique, though, is if you’ve seen enough of those casts, you can’t possibly expect that a device shaped to that casted foot position would ever fit into any shoe in our current world today.

My point is the labs we use have no choice but to dumb down that overexaggerated cast we send them in order to make something that will fit flat into a shoe and conform to the patient’s foot. Therefore, while we may be attempting to do something beneficial for our patients, at times the labs we use for orthoses have no choice but to overrule our best intentions in order to make a device that is functionally wearable for the patient in normal shoes.

In Conclusion

As you can see, there are reasons why we ourselves are the real problem both in scientific studies and day-to-day practice for why orthoses are not working for our patients the way we would really like or expect them to. We can change this in our day to day practice by expanding our foot and ankle evaluation processes, and reading current literature that may or may not back what we are doing from a scientific perspective. We have to challenge our accepted practices and make them better where we can.

As far as orthotic studies are concerned, we need to push back and demand publication of the prescriptive elements employed in any custom or OTC devices researchers use in a study. We should demand that authors publish biomechanical exam data of patients’ feet and lower extremities. We should also attempt to participate in studies whenever we can.

It would be great if we could create some exam processes that we all understand and may potentially use as well. This would assist both clinical practitioners and non-clinical researchers when working without experienced foot practitioners. This is really the only way we will end up seeing studies that will start to give us data that we can all understand, data that will begin to give us insight as to whether study authors have utilized an appropriate prescription for the feet studied.

Only then will we start to see improved outcomes with custom orthoses versus sham and OTC devices. At the very least, we can start to understand what we can do better to improve those outcomes through the use of more specific prescription devices.

Dr. Williams is the Director of Gait Analysis Studies at the Weil Foot & Ankle Institute. He is a Past President and Fellow of the American Academy of Podiatric Sports Medicine.

To read Dr. Williams’ Podiatry Today DPM Blog, see https://www.podiatrytoday.com/blogs/bruce-williams-dpm .

References

1.    Foot Orthotic Insoles Market to Surpass a Value of US$ 5.0 Bn by 2026, Says TMR. Available at https://www.marketwatch.com/press-release/foot-orthotic-insoles-market-to-surpass-a-value-of-us-50-bn-by-2026-says-tmr-2018-08-10 . Published Aug. 10, 2018.
2.    Rasenberg N, Riel H, Rathleff MS, et al. Efficacy of foot orthoses for the treatment of plantar heel pain: a systematic review and meta-analysis. Br J Sports Med. 2018;52(16):1040-1046.
3.    Whittaker GA, Munteanu SE, Menz HB, et al. Foot orthoses for plantar heel pain: a systematic review and meta-analysis. Br J Sports Med. 2018;52(5):322-328.
4.    Landorf KB, Keenan AM, Herbert RD, et al. Effectiveness of foot orthoses to treat plantar fasciitis: a randomized trial. Arch Intern Med. 2006;166(12):1305-10.
5.    Hawke E, Burns J, Radford JA, et al. Custom-made foot orthoses for the treatment of foot pain. Cochrane Database Syst Rev. 2008 Jul 16;(3):CD006801.
6.    Payne C. Foot orthotic dosing. The Podiatry Skeptic. Available at  https://www.itsafootcaptain.com/foot-orthotic-dosing/ .
7.    Redmond AC, Crane YZ, Henz HB. Normative values for the Foot Posture Index. J Foot Ankle Res. 2008; 1(1):6.
8.    Root ML, Orien WP, Weed JH, RJ Hughes. Biomechanical Examination of the Foot, Volume 1. Clinical Biomechanics Corporation, Los Angeles, 1971, p. 24.
9.    Young R, Nix S, Wholohan A, et al. Interventions for increasing ankle joint dorsiflexion: a systematic review and meta-analysis. J Foot Ankle Res. 2013; 6(1):46.
10.    Johanson MA, Cooksey A, Hillier C, et al. Heel lifts and the stance phase of gait in subjects with limited ankle dorsiflexion. J Athl Train. 2006;41(2):159–165.
11.    Dominguez G, Munuera P, Lafuente G, Martinez L. Quantification of the compensation of differences in limb length using heel raises. Foot. 2006; 16(3):130–34.
12.    Kogler GF, Veer FB, Solomonidis SE, Paul JP. The influence of medial and lateral placement of orthotic wedges on loading of the plantar aponeurosis. J Bone Joint Surg. 1999; 81A(10):1403-1413, 1999.

For further reading, see “Orthoses For Heel Pain: Essential Considerations For Optimal Results” in the August 2018 issue of Podiatry Today, “Orthoses For Plantar Fasciitis: What The Evidence Reveals” in the October 2015 issue, or the May 2011 DPM Blog “Why Orthotics Are Not The Answer For Plantar Fasciitis” at tinyurl.com/yakg5yep.