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[Case Studies] Using foot orthoses in real-world lower limb cases with Blake Withers

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In this episode with Blake, we explore how we can use foot orthoses in various different case presentations in the lower limb. We discuss: 

  • Misconceptions about foot orthoses
  • How and when to use foot orthoses
  • What conditions can respond well to foot orthoses
  • Differences between customised foot orthoses and off the shelf orthoses

This episode is closely tied to Blake’s case study he did with us. With case studies, you can see how top clinicians manage real-world cases and apply their strategies to get better results with your patients.

👉🏻 Watch Blake’s case study here with our 7-day free trial:
https://physio.network/casestudy-withers

Blake Withers is a musculoskeletal podiatrist working in a multidisciplinary sports medicine clinic and a PhD candidate researching running injuries. He lectures in biomechanics and teaches in the Sports Podiatry program at Newcastle University, is a published author, and sits on the Musculoskeletal Special Interest Group board. Blake co-hosts the top-5% global podcast The Sports Medicine Project, delivers national and international education on running and lower-limb injuries, provides global telehealth, and is a regular presenter featured across multiple leading industry platforms.

If you like the podcast, it would mean the world if you're happy to leave us a rating or a review. It really helps! 

Our host is @Sarah_Yule from Physio Network

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SPEAKER_02:

On today's episode with Blake with us, we tease out some of the concepts he talks to in the case study he has recently done on managing perineal tendinopathy with foot orthoses. Blake is a musculoskeletal podiatrist and Australian Pediatry Association educator who works in a multidisciplinary sports medicine clinic alongside several sports doctors seeing exclusively musculoskeletal conditions. He is also a PhD candidate in running injuries, a lecturer in biomechanics and the sports podiatry program at Newcastle University, and a board member of the Pediatry Musculoskeletal Special Interest Group. He co-hosts the Sports Medicine Project Podcast, is a published author in the Journal of Sports Sciences, and teaches nationally and internationally on running injury, footwear, bone stress injuries, and tendon pathology. Blake's work spans academia, clinical practice, and education, and today he shares insights based on his case study with Physio Network. You can click the link in the show notes to watch Blake's case study with a seven-day free trial. You're going to love today's episode as you can get a glimpse into how Blake's teaching can have a profound impact on your clinical reasoning. I'm Sarah Yule, and this is Case Studies. Well, welcome to the podcast this morning, Blake. Thanks so much for joining us.

SPEAKER_00:

Thank you so much for having me.

SPEAKER_02:

Let's dive into it. What are the most common misconceptions you see with regards to foot off osis?

SPEAKER_00:

Oh, great, great question. These are the questions that I go to bed dreaming about, thinking how do we best answer this? Because, you know, if we look back many years ago, the first documented foot off osis that I'm aware of is 1885 or 1883, depending on who you ask. And it's basically a foot and they have a brass metal brace. And you can imagine a piece of metal up around coming up just to your medial malleoli, like around your foot. And even back then, the goal was we want to make the foot nice and straight and make the foot nice and aligned. And a lot of those theories and kind of ways to practice have held true for a really long time. And some people are still practicing that way in 2025. And the challenge has always been with foot orthoses because they're such a safe treatment, and a lot of the time, similar with exercise, similar with mental therapy, you can have these theories and these philosophies in the way in which you think something is working, but it probably isn't. So if someone comes in with a sore medial ankle tendon, or make, let's say the tip post tendon, flexor loose longless, maybe the perineal tendon, and their foot is rolled out or rolled in, and you say, I'm gonna make this foot straight. It needs to be straight, it needs to be perfectly aligned, and you do that, they're probably gonna get better. And it might be the potentially the another reason other than what you thought. So the reason I explain all that is the misconception is we still need to make the foot straight, and we're using them to make the foot perfectly aligned with the body. We know human beings are variable. It's clear in the research that there's lots of variation in foot posture, there's variation how people respond to exercise, to various types of treatment. So, whenever we're thinking around what do we need to understand with foot or focuses and kind of where we all need to, as just in healthcare, move towards is we're just using these devices to unload a tissue that's painful. And the idea is where we remove that load, we should be able to see it potentially recover a bit quicker. Maybe we should be able to help modify someone's pain and then hopefully allow them to get back to what they want to be able to do. And I love to use this example all the time. And I want to put you on the spot, and that's why I was looking up when we were talking offline that you're a physio. Someone comes in to see you, right? And they just have pain somewhere, and they're doing all these activities and they're doing all these things and they're telling you, yep, it's definitely worse after this, and it's worse the next day. If I've done this before, in addition to education, what's one of the things that you're gonna definitely offer them to be able to help modify their pain? Let's say on the initial appointment.

SPEAKER_02:

I mean, it's sounding if they've loaded too much, we change the load.

SPEAKER_00:

Yeah, yeah. We're just gonna say, great, you know what hurts when you go for your 90-kilometer run? Let's just try 40k. You know, we're yeah, we're gonna modify the load. I use it, I really uh hyperbole there, but we're gonna modify the load. Like that's all we're thinking with foot authors. You like your heel is sore, there's something sore, your shins are sore, or just trying to modify the load. And the challenge with the foot and the ankle, and we we say this quite a lot, is it's very hard to modify the load. You've only got a little amount of real estate. The foot's relatively small, you've only got a certain amount of contact area, it's very hard to be able to manipulate the load. I mean, I like to joke because my partner's a physio, and physios have it easy. If your shoulders are sore, it's easy. The hard stuff is below the knee, as we say. If your shoulders sore, I say this to patients, if your shoulders sore, you just put it in a sling, you rest it, it's easy and it gets better, no trouble at all. Shoulders easy. But when it comes to the foot, that's where the intellects are. That's where the I'm joking, by the way, for the people listening don't know a bit uh bit sarcastic. But it is hard to modify. Yeah, I was just thinking of um, I know you guys had maybe Jared Pound, like he's listening to this going, this guy, this bloody podiatrist. But it is hard. If you're a nurse who's working eight hours a day and your heel is sore, it's a lot of compressive load, it's a lot of tensile loads, a lot of loads with a foot and the ankle. So we can use foot orthoses and other therapies as well, like footwear to help modify the load. So I feel like for me, that's the biggest misconception where even other health professionals are thinking, well, what are the indications for foot orthosis? And just like you would use heel lifts or footwear or give really good education around don't do the things that aggravate it. That's all we're we're trying to do with foot orthosis. And when we think like that, then it just opens up all these options for people where the question I always get is, well, do I need this foot orthosis for life? And then well, we know you probably don't need to modify your load for life. If you're a runner with a sore Achilles, we can probably get you back to good training, good intensity, good volume, and heals. It takes time, but we can get you there. And hopefully by the end of you and I catching up, we don't need to modify your load anymore and you don't need to see me as a practitioner. But the caveat to that is we know from the research, the most likely person to present to a podiatry practice is a female over the age of 45. And when we start to look as people get older, we see changes in hormones, we see changes in tissue physiology, we start to see these conditions where the tissue is just not the same. I mean, I'm a 29-year-old male, I like to go to the gym. If I'm doing weights, my bicep physiology and the adaption curve is very different to the cartilage in someone's midfoot. If they have midfoot ostearthritis, they have a higher BMI, they're already sedetry, they have other comorbidities present. So my second misconception is we talk around that everybody should come out of foot orthoses. And I certainly agree. I prescribe to the philosophy of I just want to use this device, just like penadol for a headache. You take it for a period of time, your headache gets better, lovely. We don't keep taking the penadol. But for some people, it's a bit like type 1 diabetes, where they're just going to rely on it. There's things within their body that makes it really challenging for them to come out. They can try everything, but they they really just struggle. And their quality of life, the things that they can do are just so much better. I mean, if you see an adult acquired flat foot, in my case, like I work three to four days a week, basically it's good exclusively muscoskeletal conditions. And I see people that have fell down the stairs and had their Liz Frank fused and have midfoot OA and post-traumatic OA and syndismosis and subtle drone OA. And I see some really unique conditions that are that are quite traumatic for people, and they might need a brace and a big supportive shoe to be able to walk 30 minutes and telling that person, hey, listen, we need to get you out of this thing. It's so detrimental to you. Like will you take them out of it? They can't walk five or 10 minutes without pain. So we can definitely say them doing 300% more activity is probably better for their overall health and the things that they want to be able to do. Now, I'd have another analogy to that is I said a bit like penetrat for a headache, a bit like type one diabetes and basically needing insulin, but it can also be a bit like type two diabetes, where you know that lifestyle modification and nutritional advice and you can do lots of things to maybe quote unquote reverse or kind of reduce the disease progression. But it's really quite difficult. And anyone, I'm sure you would hopefully you would agree with this, and everyone else would. In theory, it's easy for someone, yeah, just eat well, move, be physically active, meet the guidelines, do all these right things, and everything will be okay. And we know that's bloody challenging for people. If we had the answer to that, we wouldn't have a global crisis at the moment of obesity and comorbidities and things like that. So we might use these devices in the longer term. And yes, people may be able to come out of them, but we need to still make it about the person and asking them, like, what are your goals? These are the potential complications, these are potential adverse effects, but this is what we need to do. Are you willing to do that? Do you want to do that? And let's try because my frustration is I see and have people reach out to me and then tell me that they've tried to come out of these devices and their pain got worse, and we don't have any research on how to transition out of them. So we do want people not to rely on these without a doubt. But there are some people, it's a small part of the population that probably can come out of them, but it might be quite challenging. And there's another probably smaller part where their life is just going to be so much better. And the best evidence of that is the person in front of you telling me.

SPEAKER_02:

There's a whole lot of information there.

SPEAKER_00:

Yeah, I was going for it. I was going for it to go bang, bang, bang, poi, poi, point. I try to get it out talking 150 words a minute.

SPEAKER_01:

Ever wished you could see how experts treat real patients of theirs with case studies by Physio Network, you can. Watch presentations where top clinicians break down real life patient cases step by step, showing how they assess and treat even the trickiest of conditions. It's the best way to improve your clinical reasoning and build confidence in the clinic. Click the link in the show notes to start your free trial today.

SPEAKER_02:

For those ones that you've just mentioned, that potentially the orthosis is better for them in the longer term. Do explore with them sort of an alternating approach where they have it on sometimes and sometimes not. Explore that.

SPEAKER_00:

Yeah, yeah, we definitely do that. I can see you in my mind right now because that was a point I thought I'd better leave that. And if we touch on it, we touch on it. But yeah, that's a great point of the people that generally spend a lot of time on their feet. So the majority of people we see will not need foot orthosis. The majority of people that I work with do not need the foot orthosis in the long term once they have their betup. However, there are people that I work with that I might see every couple of years. I don't rebook them, they just kind of rebook back online and say, I'm a nurse, I'm a tradesman, I'm a doctor, I spend a lot of time on my feet. And, you know, I just wear that really soft inner sole that you gave me in my work shoes. And my work shoes just stay at work and it feels nice on my heel. I stand for eight hours a day, and we know, and you will know as well, the human body doesn't adapt as well to compressive loads. We know the insertion of the Achilles is a great example. The heel is a great example as well. If you're standing on hard floors, and that's a one of the biggest risk factors for plenty of heel pain, are is standing on hard floors for a long period of time. And it's really hard to modify that load. So if that person feels better, we might just use it for work. Then everything else, you don't need to use it. And I'm strict in the sense that I'm strict on myself in not making any promises where I say, let's experiment and see how we go. If you feel better without it, awesome, let's do that. But if you feel better with it, here are the kind of potential consequences, if there's any, other than you might need to come back and see me and pay a couple hundred bucks for a nice cushioned inner so that it's just got to experiment and we can't predict what the human body's gonna be like. I do a lot of that and my ratio changes. I do about five of those devices to about one of a cups and device. And that's something that um, you know, that that health professionals can do, probably not to the point of being able to adjust it, because we have a big grinder and we can, you know, we can adjust and we can make more force, we can make firmer material. But if someone comes in with a a relatively average foot and they have a perineal tendinopathy and we use the this kind of framework that I like to use of identify the infected tissue. So what's the diagnosis? Understand what are the bigger loads placed upon that tissue, and then choose your material. And that then brings in, well, if I'm managing a perineal tendinopathy, which is what we did in this awesome case study hosted by Physio Network plug, if I'm managing that, what lows is a tendon exposed to? Tensile, compression, shear, a combination of all of them. So if I know I can reduce and aim to reduce some of the tensile load of the tendon, how am I gonna do that? And and potentially the rate of force development as well. How do I do that? Well, that tendon, if I'm gonna try and pronate that foot, I might just put a lateral wedge down the outside, and that's gonna reduce that like the load on the tendon. Now, there's plenty of debate in well, how much material do I use? Does it need to be custom? But I've had patients come in and they just use a bit of rolled up paper down the outside and it makes their foot lift up. So we can utilize different types of material. Now, in the case study that we did, we use from Foot Sides for Morphotics. I just changed their company name. We use a medium density EVA, which is kind of similar to what you find in footwear, and it's built into the outside, it's high on the outside and it tapers down to the inside. Now, you can just stick that onto a prefabricated device, and there's your wedge, and you can try it and see how it feels. Or for some cases, and I do this as well, if it's a smaller shoe, shallower shoe, I'll just take the orthotic away and just use the wedge and just put it under the liner. Please, health professionals, please put it under the liner just because it's going to be way more comfortable. And someone teachers don't put it on top because they'll just feel the wedge. The awesome thing is I get to do that, and we all can do that, but then I get to do the other things as well. I still get to do the education, I still get to get the load modification, the rehab, all that stuff I still get to do. And this is just a simple load modifier, exactly the same way that we all use heel lives for an insertional Achilles teninopathy. So those principles hold true. Now, when it comes to a custom, and this is the debate, and I'm going to be completely transparent. We don't have the research for this to say that custom is superior, and we don't have the research to say that a prefabricated device that I'm doing is superior. We do have some research in particular conditions, like adult-acquired flat foot, that we can say that it that a custom is superior. So the difference with a custom is I take a 3D image of the foot and I make a device that is the exact shape, but the material I use is going to be more resistant to deformation. So it's going to be a bit more resilient. And what that material can do, theoretically, is it can produce more force. So I can pronate the foot more, or I can provide more of an external pronatory moment to the foot. So if I have that, then I can start to think just like a pizza base, I'm going to add these different materials on top. If I'm 3D scanning it, and this is how we make them now, we 3D print them, I can make a big flare. So I can make the device come right up the outside, I can make it stiffer, I can make it to 0.1 of a mil. So I can make the outside 3.9 mil stiff, and I can make the inside 3.2. So it essentially creates a nice, stiffer device on the outside. So that's pretty awesome and really cool. And I can make the device wide, it's made to the foot, I can put different materials, all this type of stuff, which is awesome. So that material and those modifications are going to better create more force that's going to unload the tissue. But we know that foot orthoses don't. Understanding now the mechanism, it's not just all mechanical, there's somatosensory things, there's some other psychological stuff as well. So it's not all just load. And we use the case of adult-acquired flat foot. It's a pretty wide foot. There's some physiological changes to the spring limit, deltoid tip pose. If I use an off-the-shelf device, it's just not going to fit the foot because the foot has changed so much. And I don't like to say a flat foot, but it's a flatter, wider foot. And the device is going to be more likely just to push it on the inside and just be uncomfortable. And a frustration of mine is I don't know if you've had this experience, you know, someone, a patient presents to a non-paditist and says, Yep, I've tried orthotics. They failed. They were uncomfortable. I didn't like them. And we go, yep, okay, that's in the basket of fail. Those therapies don't work. Whereas when a pet person comes to me and they say, Listen, I tried physio, I tried exercise for my Achilles tenderopathy and it didn't work. My first thought is without without even saying anything, my first thought is, Oh, that's okay. They probably maybe overdosed. Probably the exercises maybe were too much at that point. Let's talk about exactly what you did. Because, you know what? I reckon the physio probably got it right. They probably just overdose, and that happens, I would do the same thing, and I really evaluate their exercise. But my challenge to other health professionals listening to this is you should be able to evaluate a foot orthosis. Because what if they come in and they have a perineal tendinopathy and they say, I tried foot orthosis, and it was just the fact of when they put their foot in, the arch was too high and it was pushing them out. Because as a podiatrist, I can adjust that arch in 20 seconds and I can make the device feel completely different. So we need to evaluate that. So back to the custom, they are superior in some cases where, and I and I use this framework in the case study. We need more force application. Durability is a big one as well. There's asymmetry abnormalities or associated loading patterns where they have a really laterally loading, laterally deviated subtailor joint, and they have a really caverse and they put all their weight on the outside and they have a perineal tendinopathy. They're probably going to need some wedging, and we might need a wedge that's going to be more durable and be able to provide more force to be able to actually apply the force to the foot to remove and reduce some of those forces. Whereas a device that I can make in the clinic, it will still help without a doubt, and probably isn't going to help enough. So it's a it's a really nuanced conversation. And there are some cases, like I said, adult-acquired flat foot, these deformities, midfoot OA is a great one. You know, the big toe OA that I was talking around before, what we do in clinic, we use a Morton's extension, which is a two to four mil piece of 3D printed kind of plastic that sits under the big toe. And that takes the bending force, so the toe doesn't have to work as hard. And I love to say to patients, they go, Oh, is this gonna work? I said, Well, do you feel better in shoes? I go, Yeah, I love my shoes. The rocker feels great. And because the rocker is so stiff, it's essentially the same thing, but just in the within the device. So that's great examples where you can't have that on a prefabricated device because it has to be 3D printed and made. So there are definitely cases, and I said it uh said it before, but the challenge is other health professionals need to understand that and evaluate these treatments.

SPEAKER_02:

Well, like it has been incredibly insightful to explore how orthoses form a part of the treatment plan. And I think a really great reminder from you today on the relevance of using our clinical reasoning and the human skills that we have in being dynamic as we treat the patients in front of us. So thank you.

SPEAKER_00:

That's okay. I wanted to leave with one last, one last challenge. I wanted to try to challenge people to learn more about them and a potential modification. I post a lot on now, this sounds like a real shameless plug, but I do post a lot on LinkedIn and my Instagram play at SportsPods, all these different modifications and things and things that happened to me in clinical practice to help people understand. But I want to challenge people, even calling them foot orthoses, but not to call them arch supports anymore. Because when you think of that, we think it's all about the arch and it's not about the arch, it's about force application. Yes, it needs to be comfortable and needs to be contoured to the foot and needs to fit into the shoe, all those things still hold true. But when you start to think of them as a force applicator, then it starts to make sense. Well, where do I need the force to unload a tissue? And then it just makes so much more sense where if someone has an Achilles tellenopathy mid portion, I think, well, what do I need to do? I need to modify the tensile load on the Achilles. Well, how am I going to do that with a foot orthosis by changing the subtailor joint? It's probably not going to have the greatest influence, but a heel less will. And then if I think, well, if I'm trying to unload a second metatarsal head, then I can have more of that force application around the head to unload. So foot orthoses aren't a panacea. Anyone with below knee pain or knee pain, not everybody needs a device. But once you understand the loads, then you can go, well, is my device actually going to really modify the load that much? And that's why you don't see me using foot orthoses for back pain because they're probably not going to modify the loads at the back. Whereas if you see me for saying high-risk navicular stress fracture, potentially I can reduce the tensile load over the dorsum of the navicular where we know the loads are high by reducing some of that arch deformation and we might use a stiff contra device. So understanding those loads and then the tissues just makes us way better at hopefully at our prescription understanding what kind of um material we need to use.

SPEAKER_02:

I think challenge accepted.

SPEAKER_00:

Yeah, yeah, very good, very good. Yeah, thank you so much.