Shireen: Join us in today’s episode as we interview Dr. Armstrong who sheds light on the connections between diabetes, neuropathy, foot ulcers and the critical risk factors for developing these conditions and how knocking your socks off can reduce the risk of foot amputations. 

Dr. David Armstrong is professor of surgery at Keck School of Medicine of USC. He’s a leading clinical researcher in the world of limb preservation. He and his team are dedicated to eliminating amputation in people with diabetes over the next generation. Welcome, Doctor Armstrong.

Dr. Armstrong: Shireen, such a pleasure to be here. Thank you for letting me play hookie even at home.

Shireen: This is going to be a fun episode. I already know it. 

Dr. Armstrong: I’m all yours. 

Shireen: Perfect. Well, Dr Armstrong one, welcome. It’s such a pleasure having you even just starting out with the intro itself and this strong sort of vision, this, this goal that you have about, you know, we’ll get into amputation in just a second, but just starting out there, I want to sort of help our audience help our listeners just really kind of get a feel for just you and your background.

Your expertise spans from diabetes and foot care, tissue regeneration and wound healing. My gosh, that’s quite a bit of experience. How did you grow to have so many different interests? And what led you to this work?

Dr. Armstrong: Well, look, I grew up with quite literally my father who passed away about 20 years ago, the smartest man I ever knew, but he was a foot doctor. You know, he just worked in the office in Santa Maria, California, kind of north of here in Los Angeles. And so I grew up seeing how someone could really make a difference in this area, just looking at the humble foot and, and, and I learned back then, Shireen, I mean, I guess I could think of maybe two gifts to work him at the end of the body on the foot.

And I think, you know, the first one, Shireen, is that in this era of hubris and sort of chest stomping, I can’t think of anything that’s more of an expression of humility than looking after someone’s feet. You know, it spans all orders and, you know, generations of religions and, you know, even time when you think about it. 

And so there’s that and the humility that, but then also you were talking about all the things that we’re doing. Well. You know, I, I work on the end of this sort of an atomic peninsula. You know, my dad used to tell me the greatest gift you can give someone besides your love is perspective. That unique perspective at working at the end of the body kind of forces you to collaborate, if you will, with the atomic mainland. 

And so we’re working with I mean, you know, one of my closest friends is a neurosurgeon. I have a cross appointment there. I do our brain computer interface stuff all the way to folks who are working on all kinds of different tools in epidemiology to spray on and spread on skin, to wearable robots to, you know, everything else in the foot. So it’s a, it’s amazingly that little area at the end of the body is amazingly rich and, and so it’s a fun time to be doing this whole thing, fun time to be a foot doctor.

And now my daughter, my oldest, I have three girls, but my oldest, they’re all great FYI, but the oldest is now gonna be a third generation foot doctor. She’s actually an intern now at UT Health Science Center in San Antonio where I was actually a young assistant professor. So that’s the whole gang.

Shireen: I think what, what really resonated with me with what you mentioned here is, you know, working with this part of the body that is so humbling, right? Like that truly resonates. I do want to give our listeners some perspective around this episode first. I do want to provide first a better understanding for diabetes and its complications because diabetes is complicated and then you’ve got complications that are also complicated. Could you, could you start off by explaining this relationship between diabetes and foot problems? Like what, how does that relationship even exist?

Dr. Armstrong: Yeah, Shireen, I mean, there’s no reason why you should even be thinking about this. I mean, the fact is very few people care about, you know, any of these things, diabetes, but especially the foot within diabetes. I mean, and that’s one of the reasons why it’s such a big problem because I’ll just summarize it right now, it’s what you can’t feel that can really hurt you and actually can believe it or not, can kill you.

It sounds crazy. People sometimes say their feet are killing them and in this case, it’s passable, but let’s just talk about that. So because there’s a lot of bad, but frankly, there’s a ton of good and I think that’s what we’re gonna be talking about now because it’s a really fun time to be doing this because you can really make a difference.

So how does this happen? How does someone with diabetes develop a problem with their feet? Over time, folks with diabetes and I, I think you probably know there’s about 550 million folks with diabetes around the world in the United States, there’s maybe 35, 38 million with diabetes. Half of those folks with diabetes over time will develop what’s called neuropathy, peripheral neuropathy.

And what does that mean? That’s just a $5 word for just saying that you can lose some sensation and you can therefore, when you lose that sensation, you can wear a hole in your foot just like we wear a hole in a sock or a shoe. That hole is called a diabetic foot ulcer or a diabetic foot wound. So if you hear me say it an ulcer, that’s what I’m talking about.

Not in your, not in your stomach, but on your foot, those ulcers now show up every second now around the world, about half of those wounds will get infected as they’re healing and of those infections, just to hit you with some data, about 20% of each of those may end up in hospital, which is why there is an amputation around the world every 20 seconds. The bottom line is that every 20 seconds, that’s a problem we think that we can identify and potentially prevent and make a difference and we can, if we get out in front of all this. But that’s those are the data. as they exist. I’m happy to also talk to you about how these things can affect folks in terms of morbidity and mortality if you like as well. Or we could talk about that later.

Shireen: I do want to get into that a little bit, but I still want to make that connection between like how is diabetes causing this? Well, how are we losing sensation? What, what is happening there?

Dr. Armstrong: Yeah. So there are a couple of different ways that folks will lose the feeling or there’s several different kind of theories. But really the theories have to do with the fact that you’re both having hyperglycemia. So you’re, you have impaired glucose kind of control that can lead to what’s called a glycated or advanced glycated and products and glycosylated.

So what, what does that mean? That means that the, that the little baby, that the little that the tissue in your body, whether it’s tissue in the back of your eye, in your kidney, in your skin, in tendons? Yeah, can turn from being more like a tortilla and from, from that into a cracker, if you will, to use a culinary Yumlish analogy. and, and so what can happen is that can make the skin more friable and all the other tissue more friable.

But it also can make some of the micro little baby blood vessels around the nerve, more friable and that can lead to ischemia around the nerves. In addition to that, this persistent low grade inflammation can lead to destruction of the nerve as well. So there’s a whole lot of things happening, kind of at a cellular level out at the end of the body first and then it kind of works its way sort of toward the center.

So that’s why we say that these, that the neuropathy, of starts in what we call a stocking, like a stocking and a glove distribution. It affects the longest nerves first, which is why it tends to hit the feet before it hits the hands, the other parts of the body. So that is this neuropathy, there’s a lot of other little things going on. That is also why good quality nutrition, food being medicine, good quality glucose and a lipid control can potentially reduce the speed at which all of this stuff happens. 

So the good news is as people, you know, we have some control over this, even though I don’t think we have control over our genes, we do have control of our epi genes and kind of what we can do, you know, collectively to try to affect change. And I think that’s where all the information that you provide folks all around the world can make such a big difference.

Actually, in my opinion, probably even more important than what I’m doing because you know, food be in medicine, this is medicine folks are thinking about and most of the day, whereas they might just spend a few minutes in my clinic, hopefully less rather than more.

Shireen: And you know, and so with the Dr. Armstrong, I’m sure so help us understand because to the layman it may sound, well, you’re losing sensation in the bottom of your foot. Like how bad can that be? Why is that leading to ulcers? Why is I leading to amputation? How is this happening? How, how do you not know that you have an ulcer? 

Dr. Armstrong: Yeah. Yeah, Sherine. That’s right. It is so easy to talk about on a podcast or even in clinic or even if I’m talking to medical students or even family members and, or even to the patient. But what’s hard is what actually happens in understanding this and seeing this and if I were to show you one of these, a wound, one of these ones and if you just google them, you, Shireen, would have more of a visceral reaction to this thing often than our patients do.

And we would say, oh my gosh, what a dummy, how could she not have felt that when he was walking on that terrible blister or that callous? Or even when he was walking on a nail and he heard the bang, bang, bang of the nail and the it wasn’t even him that heard it, it was his grandson who heard it on the linoleum, you’d say gosh, how can you be so oblivious to this?

But if that were you, if that were me? Right. If I had something on my back, right, I wouldn’t, it didn’t hurt me right. There could be a big, I wouldn’t do anything about it until someone said, hey, what’s that? and, it’s the same thing here. What you can’t feel and can hurt you and you know what Shireen, you, you really hit on it if you were, I don’t know if you were an evil deity and you were trying to sock it to humanity.

You wouldn’t pick something that hurt something terrible like HIV AIDS or even cancer. You would pick this because it is silent and it is sinister and it is super common and it doesn’t, and, and, and folks don’t feel it until they feel it until it’s a really significant problem. I mean, I, we were just, just in the emergency department, yesterday seeing a patient, like this, they had walked on a nail for a few days and how do we know it was a few days because that’s when he was in the garage making something. Again, I, I mentioned with, actually this was with his granddaughter and there were some nails on the floor. So we, we kind of knew that but he didn’t even feel it. 

And so this problem happens all the time and it’s not his fault. Right. And it’s not. And so folks will look like us, they will dress like us. They may even eat like us, but they’re not gonna act like us because they don’t have that gift. One of my mentors, Paul Brand, used to call this the gift of pain, right? Pain is the gift that no one wants.

Shireen: That is so deep because it’s, it truly is right. What do you do when you lose that sensation? Unless you have that sensation, you do not know that you’ve been injured, right? Like you do not know about that.

Dr. Armstrong: And I can’t, we are trained, we’re trained as doctors and nurses, just as people right to respond to, to symptoms, to pain. If someone comes to me, why, why my foot hurts, right? Not my foot doesn’t hurt and, or, you know, not my back doesn’t hurt or I, I don’t have a headache or I’m not having chest pain. 

You know, and this is the challenge and this is what led me to be so fascinated with this because dealing with other types of injuries that we’re trained to deal with as physicians and surgeons nurses is, is one thing and that’s challenging enough. But dealing with the absence of it, boy, I’ll tell you that is a whole different world. And and it’s been kind of an interest of ours in mind for the longest time because of that. 

And this is the easiest thing to talk about you. And I, right now with all the folks listening, but it’s just the hardest thing to understand in IRL, right, in real life when you’re in clinic or when you’re in the operating room, right, when you’re in the emergency department, or when you’re at home and you have a problem like this. The good news though. Shireen, I’ll tell you that these problems are identifiable and preventable. And, that’s the good news. Yeah.

Shireen: And, and I would love to, that’s where I actually want to go next because help us understand. What are those key steps that a person who is listening today is a caregiver for someone who has diabetes, what are those key steps that they need to take to say, man, I do not want to go through this.

Dr. Armstrong: Yes. So there are, there are definitely steps. So let’s talk first of all about what you can do before we even talk about, like, any of the things you could do lifestyle wise. But the first thing is let’s start with the doctor and then move ourselves out back to the home. So the first thing is when you’re in the doctor’s office, what can you do? You might be in the, with a family doc and she or he may be seeing you or maybe it’s a nurse practitioner or a physician’s assistant or, or another nurse, just knock your socks off. 

Seriously just take your socks off when you go in there and that may seem ridiculous. Right. But that will cue her or him to have a quick peek at your feet because she or he on a general doctor visit have so many other things to do that that are really, really important for, for the, for your life, not just your limb that they’re going to, they might forget this.

Right. And, and, and it’s not their, not at all their fault. It is impossible to do everything that is expected of a family physician nowadays, but that’s number one. So that’ll just get him to do that. 

Number two, make sure that, at the doctorate, and then we’re gonna back our way into what you can do at home. So make sure that you are seeing your foot doctor, your podiatrist at least once a year. So, and your family doc will likely be referring you, if that’s not happening, there are really good data to show that if she or he is referring you out just doing that. 

We just had this paper recently in the journal of the American Medical Association. I’m sure we can put a link there because actually just as good to read for you as it would be for any doctor or nurse the boat, there are really good data to show that if you’re doing that, your risk for getting any of these problems like a wound or infection amputation reduces anywhere from on the low end. 20%. By the way, 20% change would be a Blockbuster drug to upwards of 80%. So this is Blockbuster effects just by seeing your generalist or your diabetologist along with a podiatrist. So a podiatrist along with another member of the diabetes team, that is what reduces this. 

And then those clinicians can identify any risk. Like if you have loss of, of sensation that’s dangerous or if you have a problem with your circulation, that needs to, and you need to see a specialist, like a gastro surgeon or if there are other issues that, that need to happen, that is a quick and easy sort of thing that you can do. Knock your socks off. Podiatrist once a, at least once a year. 

Number two is. So if you’re at home, now, what are the, some of the things you can do? So at home do the same thing, knock your socks off. Now, it may be really hard for you to see your feet or the bottom of your feet. And, you know, unless you’re, you’ve been like a Yogi and you can like, you know, you know, bend and twist your body and if you are, man, God bless you, that means that you’re a bit active and exercising and I’d say that’s great. 

But if you’re not, then have another member of the family. and that could be your significant other. It could be your grandchild or your child, just have a quick look every day. and, in doing that, that can be a lifesaver literally. And you’d say, well, what do I look for? And the answer is, well, if you’re looking every day, you would know because it’ll be different than it was a day or two ago and maybe there’ll be swelling that’s unusual maybe on one side or the other or even both, maybe there’ll be redness in an area. That’s unusual. Maybe there would be something like an ingrown nail, all these little humble things. Maybe there’s something weird in between the toes that you say, gosh, what’s that? Or maybe there’s a callus. 

So, a callus for a person with diabetes is like a breast lump in cancer. It’s a coming event and if you have a callus and you don’t have a feeling that area is about to ulcerate, so you need to see your foot doctor and I know that sounds ridiculous. Just a humble callous. But that humble callus can become a wound extremely easily and very often there’s an a wound under the callus that you can’t even see because, because you can’t really be feeling it if it were you or if it were me, we, it would hurt us so much because we have sensation that we’d be limping on the thing and we’d be in to see our foot doctor or we would have trimmed it ourselves. Right. but that’s the difference really. 

So, those sorts of things are the things you can look at and you’ll be coming in to see people all the time and we even have a program, that we call our foot selfie program where, our patients can take a picture of their feet and they ping it over to us and, and that has actually been really a limb saver as well. And we’re really trying to expand that program with resources. not only around our area but really worldwide too. So that’s just a super simple thing. But yeah, definitely take a picture of it because you can now. 

Shireen: By the way, I really like the foot selfie because it makes so much sense. It is like, you know, you can, you don’t have to necessarily have someone be live on the other side. It could be a picture that you take. So you’re not able to reach or you don’t have someone looking at the bottom of your foot, just take a picture, send it over.

Dr. Armstrong: Absolutely.This is we worked with telehealth for, for a really, really long time. And this is one of those things they call store and forward. That’s the fancy word for storing like something and being able to forward it later. But it’s just a picture for us. Right. And, and that, and that kind of thing is more and more common and that is an enormous benefit that we never used to have because most of us have these devices now. And when it used to be really exotic. 

Shireen: Are there other precautions, Dr Armstrong, that individuals can take to protect their feet in situations again where pain cannot alert them to a potential harm.

Dr. Armstrong: Yes. So there’s, there are tons of little things that, that, that you can do. A lot of those little things you can kind of garner this by talking to your primary care doctor, your diabetes specialist, or your or your foot doctor, your podiatrist. But what I’ll tell you is just some little tips is if you can help it, I know it’s easy to go barefoot around the house.But if you have any loss of protective sensation, a lot of research in this area, about 85% of your steps are gonna be in the house most of the time for an, for an average person with neuropathy. 

But again, what you can’t feel can really hurt you. A lot of these people that will step on a needle or a nail or something like that, even a little, you know, piece of a matchbox car, all these weird things that we pull out of people’s feet, those things are laying around the house and, you know, they’re, they’re not thinking about the fact that you can’t feel anything if you can at least have some slippers around the house. And if your doctor, has prescribed you prescriptive shoes, and by the way, these don’t have to be ugly shoes. They can be relatively good looking. They could just, they just need to fit you well, to a point where you’re not gonna get a wo by rubbing on an area on the bottom of your foot or on or on one of the toes.

But some of these shoes now can be worn obviously around the house. You can have a sandal that they can, you can be made to wear around the house and then out in the community. So that’s really important. 

The other thing is, you know, during the summertime, definitely wear that sandal outside. If you’re walking out on some concrete, you might not be able to feel it, but just saw a patient yesterday that went on a holiday and burned all the skin off the bottom of his feet. And again, he’s a really great guy. This is like part of our family, almost this patient, all these patients are, but it was just that he couldn’t feel anything. And he had walked, you know, across the concrete and that concrete was probably 160 °F. So that kind of thing. 

That’s what you can do if you’re in the pool and you have neuropathy, it’s ok to be in the pool. We want you to do things and, but you might want to get some of those if you can afford to get some of those aqua-socks, you know, those rubber, like rubber things that you can get relatively inexpensively to put on the bottom of your feet so you don’t get a blister on the, on the bottom of the sides of the pool.

But what I tell my patients and I don’t know if this is good doctoring advice, but I’m gonna tell you anyway, on, on the podcast is that I tell most of my patients and that they’re gonna probably think I’m a broken record, but I say I would rather you get in trouble doing something than doing nothing because if you are, if you do have a problem, you get a, you get a wound, then we’re here to see you and we can look after you and if you’re just sitting there doing absolutely nothing, well, then you’re deconditioning.

That’s no good. We just want you to be as active as possible and we’ll try to make allowances for this sort of thing. But that’s why you want to work with your, the clinicians around you and, and your family members to really affect positive change.

Shireen: I do want to get into a little bit around the difference between men and women and how this, and so I’ll actually refer back to an article that you wrote around the impact of gender on amputations, excuse me, in which you claim that diabetic and non diabetic men were significantly more likely to have a foot amputation. While diabetic and nondiabetic women were more likely to have a thigh amputation. Can you explain why this is the case and what factors really contribute to this difference?

Dr. Armstrong: Yeah. Wow Shiree, so you’re now you’re really picking out some interesting stuff. So this is really kind of inside baseball kind of statistical stuff. But it’s not because it’s also there’s a ton of kind of sociology here and and kind of social determinants here. So, let’s talk about this. So, first of all, men in the past have tended to be less apt, and and of course, there are aspects that are changing and from men, man to man or woman to woman. These are generalizations, massive generalizations that happen to be supported with data. But if from a patient to patient, it, these things may not hold up. 

But that being said in general, men are less likely to come in for general wellness checks. Unless they’re actually hurting, they’re more likely to develop many of their complications, their end stage complications of, of, of heart disease, of cardiovascular disease and metabolic diseases. So, cardio metabolic disease a bit earlier.

Women are more likely to live longer and live longer with some of the other complications. So the men are more likely to actually get an amputation than women in general around the United States and around the world. This is also particularly true for men of color and whether whether you are black or Hispanic-Latino or if you are or if you’re Native American. 

Women are more likely yes to get in in general to get a high level amputation like above the, I mean, meaning a very high level like a above the knee amputation. You had mentioned those data. That is true, in general often because they may be older when they get that amputation and they may have even more severe peripheral artery disease or PAD, peripheral artery disease also called CLTI or chronic limb threatening ischemia.

So that’s one of the reasons, we think, why we will sometimes see more what’s called a AKA above knee amputations and more maybe BAKA in men. But the most important thing is not that the most important thing is this is that many of those problems are addressable early on if they, we do what we just talked about doing she which is knocking your socks off when you’re getting into the doctor’s office, checking yourself every day at home.

You know, again, there’s a bunch of other things in terms of good quality diet that many clinicians have ignored throughout their career. But I think many of us are finding that that is even more important than some of the advice we can give people because this is something that they’re doing every day, multiple times a day that has more acculturation issues than many other things being treated by a vascular specialist. Like a vast surgeon, interventional cardiologist, interventional radiologist can be limb saving and lifesaving with endovascular and open procedures along with teaming up with the podiatric surgeon. 

And we call that team for limb preservation. We call that the toe and flow program and team. And if you have the opportunity to see that kind of interdisciplinary kind of toe and flow team, you should avail yourself to that because that appears to dramatically reduce your risk of amputation big time. So keep that in mind.

Shireen: But if we don’t, generally though, what we should do is get those foot exams done, take the socks off. I think that’s, that’s gonna be my one key thing that I remember here is take the socks off. So go to your doctor, take the socks off, knock your socks off! So even if the doctor tells you, you know that you don’t need to take your socks off and show your doctor the bottom of your feet, 

Dr. Armstrong: That’ll cause her, that’ll cause him to just, just to look, it certainly will do it for me. Right. And again, it’s not, you’re not casting any aspersions at all. Hopefully you’re not casting your socks or shoes at him or her. What it does is just directs them to that. 

Shireen: Yeah. Yeah, this has been an incredible episode. Thank you so much Dr Armstrong with that. I would love for our listeners to know how they can connect with you and learn more about your work.

Dr. Armstrong: Oh, you’re very welcome to follow us on on Twitter or as you were or Facebook or Insta, I’m sure put all that up there on the, on the list or our blog. The blog is super easy to go to. I call the diabetic foot online dot com, diabeticfootonline.com. And you’re, you’re welcome just to Google me, David G Armstrong. You’ll probably find stuff at at USC Keck School in our salsa program. But you’re very, very welcome, Shireen.

Shireen: Thank you so much, Dr. Armstrong and with that to our listeners, thank you again for joining us on another episode. We will see you in the next one. But in the meantime, you know, the drill head over to our social media on our Facebook on our Instagram and answer this quick question below this podcast episode, a social media post. How do you typically care for your feet? And what aspects of food care do you find most important or challenging in your daily routine?

Head over again to Facebook, Instagram, we will continue the conversation there and again, tell us how do you typically care for your feet and what aspects of foot care do you find most important or challenging in your daily routine. with that Dr. Armstrong, thank you so much.

Dr. Armstrong: What a pleasure.

Connect with Dr. David Armstrong:

Website

Instagram

Facebook 

Twitter

LinkedIn 

Wikipedia Page