David Armstrong, DPM, MD, PhD
- Professor of Surgery at the University of Southern California Keck School of Medicine
- Founder and co-Director of the Southwestern Academic Limb Salvage Alliance (SALSA)
- Founder and co-chair of the International Diabetic Foot Conference (DF-Con) – the largest annual international symposium on the diabetic foot in the world
- Co-Editor of the American Diabetes Association’s Clinical Care of the Diabetic Food – now in its third edition
- Appointed Visiting Professor of Medicine at the Manchester College of Medicine
- Produces more than 475 peer-reviewed research papers and over 80 book chapters
- Appointed Deputy Director of Arizona’s Center for Accelerated Biomedical Innovation (ACABI)
- Youngest ever recipient of the ADA’s Roger Pecoraro Award – the highest award given in the field.
- Selected as one of the first six International Wound Care Ambassadors
- Recipient of the inaugural Georgetown Distinguished Award for Diabetic Limb Salvage
- In 2008, he was the 25th and youngest-ever member elected into the Podiatric Medicine Hall of Fame
- He was the first surgeon to be named University Distinguished Outreach Professor at the University of Arizona
- The first podiatric surgeon to become a member of the Society of Vascular Surgery
- The first US podiatric surgeon named fellow of the Royal College of Surgeons, Glasgow
- Past Chair of Scientific Sessions for the ADA’s Foot Care Council
- Past member of the National Board of Directors of the American Diabetes Association
- Former commissioner with the Illinois State Diabetes Commission
- Sits on the Infectious Disease Society of America’s (IDSA) Diabetic Foot Infection Advisory Committee
- US appointed delegate to the International Working Group on the Diabetic Foot (IWGDF)
- MS: University of Wales College of Medicine
- PhD: University of Manchester College of Medicine
September 11, 2020
Podiatric surgeon Dr. David Armstrong talks about following in his father’s footsteps, an exciting gene therapy study, and explains why pain can be a gift for people with diabetic foot ulcers.
- Following in his father’s “footsteps” to be a foot doctor after seeing how he was able to help people feel better and how his oldest daughter is going to be a third generation foot doctor
- How looking after one’s feet is the ultimate expression of humility across many religions and cultures
- How people with diabetic foot ulcers don’t have “the gift of pain”, which means that they don’t experience pain and the sore can get infected, requiring an amputation
- How diabetic foot ulcers don’t always kill people because of amputation or infection but because they make people don’t move around on it and have heart attacks or strokes
- How preventing amputations and complications is a team sport requiring many different specialists and how much that team can help patients
- How type 2 diabetes can be prevented or reversed and what that means for amputations
- The psychological implications of foot amputations, since the foot is so important for people to move around and experience life
- The dangers of a sedentary lifestyle and how new wearables make it so much easier to keep track of steps
- Trials he’s currently working on including a spread-on skin for wounds and the first ever FDA-approved study of gene therapy for wound healing in patients with peripheral artery disease and wounds
- Upcoming technologies like smart socks that can identify hotspots and even pressure points, smart insoles that can warn you about diabetic foot ulcers, and even a smart bathmat that can identify ulcers
- How animals like dogs have proven to be useful to identify low blood sugar and even bladder cancer while maggots can be used to clean wounds
- How even though he spends a lot of time explaining to patients that what they’ve found online is wrong, the online healthcare space is very important to help people learn
- How video is such a valuable learning tool
- “I didn’t always want to be a doctor, but I kind of stumbled around a little bit throughout my formative years. But I saw how the ability to do this and how to help someone move through the world a little better is just a great gift.”
- “I’m a foot doctor and you have vascular surgery, we call that combination the “Toe and Flow” model. And then you add on physical therapy and we call that “Toe, Flow, and Go.” And then on top of that you can add diabetology, nurse case managers, infectious disease, and all of these other team members. And what you end up getting is a really, really dynamic group that’s dedicated to reducing the risk for people losing their legs.”
- “I think we as doctors and clinicians in general have to kind of check ourselves when we say ‘Hey, live healthy.’ I mean that’s kind of ridiculous to be able to think we could prescribe that. But the good news is that it is extremely possible now for a lot of people to do that.”
- “People will talk about running as being natural, but certainly walking is and when you remove that ability to get around – that bipedalism, so to speak – it’s something kind of fundamental and carnal and it’s a central kind of thing to what makes us feel human. When you take that away, it’s profound.”
- “If people with diabetes just see their foot doctor along with one other member of the diabetes team (it doesn’t even matter who that person is – it could be a nurse practitioner, it could be a diabetologist, it could be a general practitioner, family doc, gerontologist, whomever – just those two people), in the next six years, their risk for an amputation goes down anywhere from just under 20% (which would be great) to almost 70%.”
- “CRISPR-Cas9: we had a technical review on this several years ago, John Sessions and me. But this is something that may play a role in tissue repair and wound healing. It’s still very early days right now for active therapy in patients with wounds.”
- “We have tons of other so-called smart technologies, everything from (no kidding) smart socks that can identify hotspots and even pressure points to smart insoles that can do the same thing and tell you when you’re about to get a diabetic foot ulcer and warn you about that.”
- “Larvae or maggot debridement therapy, has long been a thing and there are data from our group and from others to show that you can use maggots. You can buy them now from some places in the United States and they come sterile. You apply them onto the wound and they can actually clean up a wound pretty well.”
- “Well, my pop used to tell me – and I’m sure this is on a poster somewhere, but he was the first person to tell me this, that folks don’t care how much you know until they know how much you care. I saw that in him.”
- “Do I spend a lot of time in clinic talking to patients about good advice and bad advice they might find online? Sure. But is that better than having no conversation at all? Absolutely.”
There's nothing that's more of an expression of humility than looking after someone's feet. Right? I mean, it's just true. It's biblical. It's Talmudic, it's in the Qur'an, if we go into South Asia, across continents and across socioeconomic status, looking after people's feet is an expression of humility.
David Armstrong, DPM, MD, PhD
Taking care of these patients and looking after them and helping them move through the world is inherently a team sport. Many years ago, we looked at successful models across medicine and found that when you try to put people together to care about this problem, that the sum is greater than the parts.
David Armstrong, DPM, MD, PhD
You hear that a picture is worth a thousand words? Well, maybe a video is worth 10,000 or 100,000. And it just scales up. I think many of us are visual creatures in a lot of ways and if we can get that medium, through that mechanism, then all the better.
David Armstrong, DPM, MD, PhD
Daniel Lobell: (00:02)
Alright. On the line with me is Dr. David Armstrong. Dr. Armstrong, welcome to the Doctorpedia show. How are you?
Dr. David Armstrong: (00:15)
It is an absolute pleasure. Thank you for letting me play hooky. [Laughs].
Daniel Lobell: (00:20)
[Laughs] So is that a thing for doctors too? You know, the doctor doesn’t want to go in to be the doctor?
Dr. David Armstrong: (00:28)
Well, normally it would be the case but in fact, thank goodness, I’m calling you from my house because the surgery I was supposed to be doing today was just canceled because my patient, G-d bless her, is doing well so she doesn’t need it. She’s healing despite me, which is–
Daniel Lobell: (00:53)
–the best case scenario, right?
Dr. David Armstrong: (00:54)
Isn’t that the case? We always say that sometimes the best surgery is the one we never had to do.
Daniel Lobell: (01:01)
What happens if we figure out how to be really, really healthy as people and we don’t need doctors anymore? What are you guys going to do?
Dr. David Armstrong: (01:09)
Oh dang, I don’t know. Maybe play hooky more often? You and I can chat a little bit more. So there we go. I’m just going to take a sip of my coffee. This is a little bit like a kind of adult daycare for me right now. Hold on a second. [Takes a sip of coffee]. Oh that feels better. And now we can chat some more.
Daniel Lobell: (01:24)
The sweet taste of not having to do surgery.
Dr. David Armstrong: (01:28)
[Laughs] There is that. It’s a pleasure to meet you.
Daniel Lobell: (01:32)
Pleasure to meet you as well. And on the topic of meeting you, let’s hear a little bit about you. I like to get the background of the man, the person behind the doctorate.
Dr. David Armstrong: (01:42)
Daniel Lobell: (01:43)
So tell us where you, where did you grow up? And maybe some things from your childhood that would indicate to us why you might have become a doctor.
Dr. David Armstrong: (01:55)
Sure. I was born and raised in a little farming town north of Los Angeles called Santa Maria, California. A lot of my friends that used to be farmers that I grew up with, they’re all vintners now with all their fancy wineries. So it’s all a very high standard back there. But my father is the smartest guy I ever knew. He passed away about 15 years ago, but he was a doctor – he was a foot doctor, as it were. And I grew up in many ways in the office and following him into the hospital. I saw from an early stage how awesome it was to be able to – especially in his line of work – where someone could walk in hurting and kind of walk out, often feeling a little better, sometimes in the same day. So that to me was, I saw that right away even just as a little kid and that was kind of suffused in my whole of it all the way through. So I didn’t always want to be a doctor, but I kind of stumbled around a little bit throughout my formative years. But I saw how the ability to do this and how to help someone move through the world a little better is just a great gift.
Daniel Lobell: (03:20)
So I guess it’s fair to say you followed in your father’s footsteps…?
Dr. David Armstrong: (03:24)
Oh, you went there. G-d, you went there.
Daniel Lobell: (03:28)
I don’t know, I felt like it was low hanging fruit. I couldn’t resist.
Dr. David Armstrong: (03:32)
Okay. Can I just tell you? We can go as much as you want there. As a toe doctor, as a foot doctor, I get those quite a lot. In fact, our blog has a whole bunch of witticisms, you know our group is called SALSA or the Southwestern Academic Limb Salvage Alliance. And we have a whole bunch of salsa-isms on there and it just keeps adding on. There’s like hundreds of them.
Daniel Lobell: (03:58)
Dr. David Armstrong: (04:00)
But listen: thank you for going there. And by the way, my oldest daughter is going to be a third generation foot doctor. Can you believe that? But yes. There’s a lot of footstep following.
Daniel Lobell: (04:17)
Yeah. Wow. That seems to me like the people you want to go to for your feet is when it’s generations of foot knowledge.
Dr. David Armstrong: (04:24)
I suppose so. [Laughs] It’s almost like it’s like a foot cartel or something.
Daniel Lobell: (04:34)
Yeah. It’s funny to me when I think about feet, you know, you often hear that there are people who have foot fetishes, right?
Dr. David Armstrong: (04:41)
Daniel Lobell: (04:41)
But you don’t hear that about hands or anything. For some reason people–
Speaker 3: (04:45)
–You don’t. And you wonder why. I mean there’s all kinds of other body parts, but we at the end of the body, I think even though we’re at the end of the body, we get the short shrift there. But you know, if you think about it, there’s nothing that’s more of an expression of humility than looking after someone’s feet. Right? I mean, it’s just true. It’s biblical. It’s Talmudic, it’s in the Qur’an, if we go into South Asia, across continents and across socioeconomic status, looking after people’s feet is an expression of humility. But it’s also pretty cool because when you’re out there at the end of the body, maybe not taking yourself so seriously like you and I were talking about at the outset, but maybe taking the work seriously, it gives you this great gift of perspective. And we’re working on the foot at the end of the body on this sort of anatomic kind of peninsula, if you will. If you think about it, you’re sort of hostage to everything that comes from the anatomic mainland, meaning like the circulation, the nerve supply, so much else. And so it forces you to either just have the most boring life imaginable out there on the peninsula (which could be great, I guess) or you could collaborate with the anatomic mainland and our group has kind of chosen to do the latter in kind of a team approach to what we do.
Daniel Lobell: (06:36)
Can you talk a little bit about that? What does that mean that you’re collaborating with the anatomic mainland?
Dr. David Armstrong: (06:42)
Well gosh, what an exotic kind of weird high concept thought! I’m not going to give you a high concept answer, but what I will tell you is that I told you that my dad worked on people to try to eliminate pain and symptoms for a lot of people. Well, it’s kind of funny that in a lot of ways, I sort of do the opposite in that I work on people very often with diabetes. And so folks with diabetes, over time they lose what one of my old mentors used to call “the gift of pain.” They can wear a hole in their foot – like you or I would wear a hole in a shoe or a sock – and that hole is called an ulcer, a diabetic foot ulcer. That happens now every 1.2 seconds around the world.
Daniel Lobell: (07:41)
Dr. David Armstrong: (07:41)
Yeah. And then about half the time those sores will get infected. And let’s understand that a lot of times our patients, these are like family members, right? I mean, they could be close relatives or people that you might know, but they don’t have this gift, so they’re not going to behave the way you or I would. And so that about half the time these ulcers are going to get infected. And then I told you every 1.2 seconds, someone gets one of these diabetic foot ulcers and every 20 seconds now around the world, someone gets an amputation.
Daniel Lobell: (08:18)
Oh my G-d, wow.
Dr. David Armstrong: (08:19)
Yeah, I know. And just let me set all this up to tell you why it’s important to team up because once someone gets that ulcer, once they get that amputation, the five year survival for folks is worse than all but the worst cancer. About half of people are dead in between three and five years.
Daniel Lobell: (08:47)
And why is that?
Dr. David Armstrong: (08:48)
Well, it’s because when you get diabetes, when you get a diabetic foot ulcer, when it gets infected, if, let’s say G-d forbid you have an amputation, you’re not going to die of the amputation per se. Usually people don’t die of the infection, although that does happen. Most of the time folks pass away because they’re not moving around a lot and it lays them up. They never get out of bed. And so they tend to die of heart attacks and strokes or other complications like that. And so that’s what’s so sinister about this problem is that people tend to blame, not the amputation, but “oh well his heart gave out” or “he had a stroke” or “she did.” And this is what’s so sinister about this problem is that now this problem, I mentioned it being like cancer, it’s now more expensive to treat this in terms of direct costs than the five most expensive cancers in the United States. And by the way, you and I are chatting and there are plenty of people right now chatting about breast cancer, I’m sure, and colon cancer and skin cancer and lung cancer. And there should be, I mean, we need to do that to make a difference, but I can guarantee you that you and I are the only people talking about feet in diabetes. So you want to talk about an unmet need? There you go. And you asked about teams. Taking care of these patients and looking after them and helping them move through the world is inherently a team sport. Many years ago, we looked at successful models across medicine and found that when you try to put people together to care about this problem, that the sum is greater than the parts. And so what we have done at our place here at the University of Southern California, at USC, and our centers here in LA, as well as in centers around the world – yesterday, I was just in Perth in Australia. I got home yesterday and we just helped to work with other teams out there to build those teams up. These teams are now getting more popular around the world and you have podiatric surgery like me, so I’m a foot doctor and you have vascular surgery, we call that combination the “Toe and Flow” model. [Laughs]. And then you add on physical therapy and we call that “Toe, Flow, and Go.” And then on top of that you can add diabetology, nurse case managers, infectious disease, and all of these other team members. And what you end up getting is a really, really dynamic group that’s dedicated to reducing the risk for people losing their legs. And as an example, tomorrow we have our sort of flagship clinic at our hospital, at Keck Hospital and that clinic is going to have all these people in there from vascular and podiatric surgery to plastics to people who are experts in shoes and orthotics and prosthetics to all of these other characters. And it really is super fun because it’s just a lot more fun to work with your teammates who have different skills and who are kind of keeping you (so to speak) on your toes.
Daniel Lobell: (12:49)
“On your toes”… [Laughs]
Dr. David Armstrong: (12:50)
I didn’t mean to go there, by the way. You made me go there. I’m just going to say, you made me go there – full disclosure. But I need another sip of coffee. Pardon me. [Takes a sip of coffee.] But there we go. That’s really what makes this joyful, an exciting time even when it’s so hard being a patient with these complications and working to try to preserve a limb, having this team approach around the patient is really a blessing. And when you do that, when you put these teams together, really good things happen. We have found that you see dramatic reductions in amputations and folks getting back to living their life much more quickly. And so that is kind of the reason that we get up for work in the morning.
Daniel Lobell: (13:50)
Wow. So you guys are like the Foot Avengers.
Dr. David Armstrong: (13:55)
[Laughs] I guess so! Nicely done, man. Do you have to boil everything down to a superhero kind of a franchise, now?
Daniel Lobell: (14:04)
I think nowadays that’s standard protocol.
Dr. David Armstrong: (14:09)
Fair enough. I “Marvel” at your ability to do that. [Laughs] That just happened. That was bad. you can cut that out.
Daniel Lobell: (14:17)
[Laughs]. We’re talking about prevention here, which kind of goes back to the beginning of the call of “what if people get so healthy they don’t need you?” It seems like you’re working towards that, which is great.
Dr. David Armstrong: (14:36)
Yeah. Go ahead.
Daniel Lobell: (14:37)
What I was gonna ask you: diabetes, is that considered a reversible disease at this point?
Dr. David Armstrong: (14:49)
That’s a great question. By the way, even if you didn’t ask a good question, I would say that’s a great question, but may I say that’s a great question.
Daniel Lobell: (14:57)
Thank you. [Laughs].
Dr. David Armstrong: (14:57)
There are two main kinds of diabetes – there are three or four other kinds of diabetes – but the two main kinds of diabetes are type one diabetes, which used to be called juvenile onset, is not necessarily reversible now with the possible exception of certain kinds of transplantations of cells. But that’s a whole different discussion. Type two diabetes, which people used to call adult onset diabetes, but which is now happening in younger and younger people, so we usually just call it type two diabetes – is maybe at the very least preventable and at very most, reversible in some cases. But let’s talk about the preventable part and then we can talk about the reversible and then we can kind of boil it all down to what I do, which is amputation prevention. First, the preventative–
Daniel Lobell: (16:05)
–Can I say, we’ll take it step by step? [Laughs]
Dr. David Armstrong: (16:08)
[Laughs] Oh, yes, nicely done. You sort of tiptoed up to that one, but good. Okay. Here we go.
Daniel Lobell: (16:15)
This is ridiculous but I’m having fun.
Dr. David Armstrong: (16:17)
I don’t know how you’re going to edit this.
Daniel Lobell: (16:21)
I’m going to tiptoe around it.
Dr. David Armstrong: (16:21)
Okay, good on you, man. But to that end, let’s start with the preventing part. If someone has what’s called pre-diabetes, which is also known as impaired glucose homeostasis, that means they’ve got a little bit of a high blood sugar, but it doesn’t quite qualify as having diabetes.
Daniel Lobell: (16:45)
I qualify in that bracket, by the way doctor.
Dr. David Armstrong: (16:47)
Well there you go. So this is directly apropos to you. So while this is not a good place to be, it is a good place to be because you have the capacity to reduce the risk of yourself, almost like seroconverting to full-blown diabetes. Just as if you had, G-d forbid, you know, if you were HIV positive, seroconverting again to AIDS. So you have the ability to change this. And there are data now – and these are strong data – that show that if you are just active, meaning if you get 20 minutes a day or 30 minutes a day, three or four times a week and if your doctor thinks it’s appropriate, he or she might put you on a certain kind of drug like there’s a drug called Metformin that can reduce your risk of developing diabetes by upwards of almost 60% – I think it’s about 58% – based on those data. So that’s really good news if you have what’s called pre-diabetes, because you have the capacity to do that. Now let me just tell you, you have the capacity and it’s really easy for the two of us to talk about this, but it’s an easy thing to talk about and it’s a hard thing to do, especially if you’ve been living, you know, 30, 40, 50 years one way, and then all of a sudden someone says, “hey, change everything. Change the way you eat, change the way you’re doing everything.”
Daniel Lobell: (18:19)
Dr. David Armstrong: (18:19)
I think we as doctors and clinicians in general have to kind of check ourselves when we say “Hey, live healthy.” I mean that’s kind of ridiculous to be able to think we could prescribe that. But the good news is that it is extremely possible now for a lot of people to do that. So that’s really good news. So that’s on the preventing, kind of the seroconversion if you will. Another thing is that we definitely have seen more and more folks that are really, really morbidly obese. If they get down to a point after they have a gastric bypass or certain types of gastric surgery, bariatric surgery, be so successful that their glucose measurements (also known as their Hemoglobin A1c level) gets down to a point that does not classify them as having diabetes. And that has happened and it does continue to happen as well. So those are two ends, just kind of book ends of the spectrum with the patients with type two diabetes, which by the way, just so you know, type two is like about 90+% of people with diabetes in most countries now. Type one is the kind where you see little guys and gals often giving themselves injections and continuing on through their life. Whereas type two, you can also give yourself an injection, but usually you can either give yourself an injection or take a pill or modify your diet. So the treatments are slightly different.
Daniel Lobell: (20:03)
Thank you for clarifying that. We started with prevention and we talked a little bit about reversing pre-diabetes. Then we talked about diabetics – just to break this down – who have taken on themselves weight loss or extreme amounts of weight loss. And then we’ve seen the effects of diabetes go away, you’re saying. Aren’t there people with type two diabetes that it’s not caused by weight?
Dr. David Armstrong: (20:30)
Yeah. So you can definitely have folks that have – that’s another really great question – there are people, first of all, there’s some people that can have – not to make this too kind of inside baseball – but you can have someone that has kind of characteristics of type one diabetes and type and we call that type one and a half diabetes. But you can also have certain folks that look to you and I to be just completely normal in terms of they’re not overweight at all based on any kind of classic classification. But they may have a fat that is called visceral fat that’s kind of kind of right around their organs and in their belly area that’s really insulin resistant. And that can trigger folks developing what is classically type two diabetes. So we do see that and you see it in the United States, you see it around the world. It’s really common. I was again just in India not too long ago, you see a lot of it in India where you see people that would kind of almost look thin but might have characteristics of type two diabetes. So yes, that’s a good question. But, you know, look, I’m barely a foot doctor. I’m certainly not a diabetologist. I’m happy to speak to that, but you could also speak to some of my buddies who are world renowned in that area. It’s a fascinating area. But there are things you can do even when you’re at that point to improve your insulin sensitivity.
Daniel Lobell: (22:10)
The foot holds up the whole body, right?
Dr. David Armstrong: (22:13)
Daniel Lobell: (22:13)
The foot is so powerful. And you mentioned just how powerful it is that somebody who loses their foot often then loses their life as a result of not having the foot. Right?
Dr. David Armstrong: (22:27)
Yeah, you know it really is. One of my friends here at USC is a guy named Dave Raichlen and Dave is one of the top guys in the world. He’s an anthropologist. He’s one of the top guys in the world in early modern human mobility and function. And the two of us have common cause in this area because we talk about this kind of stuff all the time. How kind of just central it is to us being like a human to walk and want to walk around. And some people will talk about running as being natural, but certainly walking is and when you remove that ability to get around – that bipedalism, so to speak – it’s something kind of fundamental and carnal and it’s a central kind of thing to what makes us feel human. When you take that away, it’s profound. And you hit on it but I see it every day in our patients and I see it often slowly in our patients, even when they just develop what we call neuropathy, which is losing that ability to feel pain. That’s what I talked to you about at the onset, because when you can’t interact with the world as much, it kind of dulls (figuratively and literally) your senses, you know what I mean?
Daniel Lobell: (24:12)
Dr. David Armstrong: (24:13)
I feel like we’re talking about like Spinoza now and not podiatry, but you can really get into that whole thing. But anyway, carry on. Sorry.
Daniel Lobell: (24:23)
Well my point I think is kind of what you spoke to just now. It’s just such a central part of humanity. I’m not a psychologist, but I think there must be something deeply psychologically connected between the foot and the excitement for living, right?
Dr. David Armstrong: (24:41)
Yeah. Again, here’s something for you. One of my good friends, Dean Wukich, Dean is not a foot doctor, but he’s an orthopedist. And he and his colleagues had a paper (he’s in Texas now, but he had a paper when he was in Pittsburgh) that was really profound. He looked at a large number of patients that he had been treating and he found that those folks that were at high risk for amputation feared amputation more than death. And it was profound and stark and you hit on it. I think it’s something that is there. But the good news is that this whole thing is preventable. And by the way, even for people that develop it, that go on to an amputation, unfortunately that’s, G-d knows that’s not the end of the world. Getting people moving – there is an area on which we really focus and just as if someone were to G-d forbid lose their leg from an IED in Helmand province or in Kandahar, so too they can often get back to living their life as a young man or young woman. The same thing can happen with an older person, slightly older with diabetes and it’s not the end of the world. And I think many of our patients that come in to see us even after they’ve had an amputation, maybe at another facility, feel like it’s the end of the world, but it really is not. And so working with the team – and by the way, sometimes that includes not just us, but members of our team that are behavioral specialists – there is light at the end of that tunnel. It’s not a dark tunnel. I know I painted it that way at the outset just because the data for this stuff are so stark. But the data for a team approach for this thing gives you a lot of light. This is one of these things, here’s another example – and forgive me for going on like this – but something really simple: if people with diabetes just see their foot doctor along with one other member of the diabetes team (it doesn’t even matter who that person is – it could be a nurse practitioner, it could be a diabetologist, it could be a general practitioner, family doc, gerontologist, whomever – just those two people), in the next six years, their risk for an amputation goes down anywhere from just under 20% (which would be great) to almost 70%.
Daniel Lobell: (27:27)
Dr. David Armstrong: (27:28)
Yeah, I know! 5% relative risk reduction would be like a blockbuster drug. But here you’ve got these numbers that I just blurted it out to you. And by the way, usually the less you need something in medicine and surgery, the better it works, unfortunately. This is just the way of the world. However, in this case, the more you need it, like the more the chips are down in terms of your risk factors, the better it works. So those 70% numbers that I was giving you? Those things are when someone is at super high risk for amputation. And so you can see that it’s really pretty great when you start looking at all the terrible numbers and then you start looking at a lot of the good ones. We had a paper not too long ago with me and my friend Andrew Bolton (one of my mentors) and another guy, Sicco Bus. What a great name – Sicco.
Daniel Lobell: (28:38)
Dr. David Armstrong: (28:39)
Yeah. He’s, he’s not a doctor though. He’s more of a scientist. So it’d be better if he was a doctor.
Daniel Lobell: (28:43)
Dr. David Armstrong: (28:45)
But we had this paper in the New England Journal and we looked at all of the best available data for this problem. And when you first look at it, a lot of the numbers look really bleak. But when you look at it in a broad context about the value of team and technology and if you will, tenacity, it starts to look a lot better because you can really make a difference as a patient and as a clinician.
Daniel Lobell: (29:22)
What effect has the work you’ve done had on your own personal keeping of your health?
Dr. David Armstrong: (29:28)
Yeah, terrific question. I think a lot of times, there’s a joke, you know, “doctor, heal thyself” kind of thing and “do as I say, not as I do.”
Daniel Lobell: (29:42)
It’d be funny if you tell me, “I live a mostly sedentary lifestyle…”
Dr. David Armstrong: (29:46)
Man, trust me when I tell you: boy, do I feel you. I feel you because I don’t have neuropathy, how’s that? But the point is that one of the things that we’ve been doing over a very long period of time is that we have been measuring activity a great deal in people with diabetes and trying to dose activity like we dose a drug. And for the longest time, that’s been really hard to measure. I’ve been thinking about it ever since the eighties and early nineties when I was a student all through my training and as a young assistant professor now as a full professor of surgery, as it were. But what we’re able to do now, and what I’ve tried to do as much as possible is just move. I think kind of gamifying that activity, from everything from just a smartwatch, which is now so ubiquitous on people, to simple, smart phones. These things used to cost us – even 15 years ago, they would cost us – I once spent almost a million dollars in a big study just on these pedometers. But now these things are almost free as part of your smartphone or certainly with any of the wearables that you have. So a lot of the work that we’ve been doing with wearables since way before they became wearables has really helped inform me and try to help me try to practice what I preach a little bit. And I think that’s been really helpful, to be frank.
Daniel Lobell: (31:35)
Yeah. I read somewhere recently that sitting is the new smoking. Have you heard that?
Dr. David Armstrong: (31:41)
Oh, good on you, man! I use that all the time. Oh yeah, absolutely. It is true. It is absolutely true.
Daniel Lobell: (31:52)
Yeah. Sitting – it’s a lot cheaper, I think, than smoking, though.
Dr. David Armstrong: (31:58)
[Laughs] Depending on where you get your cigarettes, I guess. And don’t even mention vaping.
Daniel Lobell: (32:03)
What are some of the big misconceptions you think that people have about what you do?
Dr. David Armstrong: (32:08)
Yeah. First of all, people will come in with a really severe problem. We’ll talk about two ends of the spectrum. So first let’s go on one end of the spectrum. People will come in with such a severe problem and then they’ll think that it’s already kind of a fait accompli that they’re going to lose their leg. And there’s so much we can do even with very severe problems now to so-called do limb salvage and to salvage an extremity both surgically and medically, mechanically. So that’s one kind of misconception I think a lot of people feel, so they’ll just sit around and sometimes they’ll sit around cause they’re afraid to come into the doctor and they’re afraid that that’s going to lead to something like an amputation. And unfortunately, sometimes people wait so long that it becomes a foregone conclusion. It’s like it’s a self fulfilling prophecy. So that’s one thing on one end. And then on the other end of the spectrum, there are plenty of people that think that just because they are, you know, younger, they may have been diagnosed with diabetes and don’t have a lot of complications, that they should avoid the doctor. Those folks I think could really benefit even if it’s just for an annual visit to their generalist and certainly to their foot doctor. So I would say those are two misconceptions on both ends of those spectrum where a difference can be made and where I believe the data really guide us that that’s probably best. That’s what I’ll for sure tell you. And what’s really cool, I mean, there’s just so much stuff that we’re working on every day that’s exciting in the area that makes that a possibility.
Daniel Lobell: (34:17)
Can you tell me about some of that?
Dr. David Armstrong: (34:18)
Sure! Gosh, there’s so many things, but let me just tell you about a couple things. I’m the principal investigator at our place at USC on a number of studies. I’m a nationwide principal investigator on studies when you can just take a small amount of skin – this is for people with wounds – and then send that off to the laboratory and have that piece of skin modified and amplified. It comes back in about a day by FedEx, and then you can sort of spread it on a wound just like you’d spread something on – it’s like a spread-on skin, so that’s pretty cool. You’ve heard of spray on skin as well?
Daniel Lobell: (35:11)
Dr. David Armstrong: (35:11)
I was just, I was just in Perth yesterday with a friend of mine, Fiona Wood. She’s just awesome and she started a company called Recell and they have a spray-on skin as well. That’s exciting. That’s one thing. We’re getting ready to get started on the first ever gene therapy study on which I’m lucky enough to serve as a nationwide principal investigator and that–
Daniel Lobell: (35:44)
–Can I guess what that is?
Dr. David Armstrong: (35:44)
Daniel Lobell: (35:44)
It’s where you collect a bunch of therapists named Gene. And you have them… [Laughs]
Dr. David Armstrong: (35:48)
Oh? That’s exactly right. Yes, they do. And they sit down. And what is remarkable – they’re all named Gene, but you know, in many ways they’re so different. All of these Genes. And they sit down and they express themselves differently. It’s really just different Gene expression.
Daniel Lobell: (36:07)
Wow, well played.
Dr. David Armstrong: (36:11)
I’m here all week. And it’s healing. They speak to the soul, as well. But back to that, this really is – it is gene therapy. It is the first ever FDA approved study of gene therapy for wound healing in patients with what’s called peripheral artery disease and wounds. And so that’s exciting. On the other end of the spectrum–
Daniel Lobell: (36:45)
–Wait, wait, wait. Before you go to the other end of the spectrum, this is really fascinating, what you just said. Is there a possibility, let’s say, there’s some gene that I wish I had – are we getting to the point where we’d be able to do a genetic transplant?
Dr. David Armstrong: (37:01)
Wow, good. So there’s so much to unpack there. I’ll be quick in saying that you may have heard – at least over the last couple of years – one of the really great revolutions in therapy has been what’s called CRISPR-Cas9 and so-called gene editing. While this is still–
Daniel Lobell: (37:35)
–Why do you think I might’ve heard that? I would never have heard that.
Dr. David Armstrong: (37:38)
Well, will you just Google it while we chat? And then I’ll just talk a little bit and then by the end you’ll maybe have a good question.
Daniel Lobell: (37:45)
Dr. David Armstrong: (37:45)
[Laughs] But anyway, CRISPR-Cas9: we had a technical review on this several years ago, John Sessions and me. But this is something that may play a role in tissue repair and wound healing. It’s still very early days right now for active therapy in patients with wounds. But I believe strongly that especially as we get early experience with our initial promising study that we’re going to be starting with gene therapy in this initial study this next year – stay tuned. That’s for sure. Do you want me to go to the other end of the spectrum now?
Daniel Lobell: (38:31)
Alright. Let’s go there.
Dr. David Armstrong: (38:32)
Okay. Here we go. Okay, we’re going to go there. So on the other end of the spectrum, we have tons of other so-called smart technologies, everything from (no kidding) smart socks that can identify hotspots and even pressure points to smart insoles that can do the same thing and tell you when you’re about to get a diabetic foot ulcer and warn you about that. So those things exist. And the department of veterans affairs has just, I think, begun work with a smart bathmat (no kidding) where you’d be in the bathroom and you could be standing on it and it might say, you know, “Mr. Jones, your big toe is hotter than your other big toe and it looks like you’re about to get an ulcer there. Why don’t you go in to see Dr. Armstrong there on Friday? We’re going to make you an appointment.” That is a thing now–
Daniel Lobell: (39:30)
Dr. David Armstrong: (39:30)
–and the data on some of these things are really promising. We shall see how all of this progresses. Because many of these companies will come and they’ll go. But the idea from some of these startups is super exciting, I think.
Daniel Lobell: (39:50)
Yeah, that’s fascinating. And it actually reminded me of an article I read a long time ago about a guy whose dog was like furiously licking his feet and it turned out that he had stimulated some cell – the guy was going to have an amputation.
Dr. David Armstrong: (40:09)
Daniel Lobell: (40:10)
Does any of this make sense to you?
Dr. David Armstrong: (40:12)
You mean that somehow the dog licking the wound help to cause the wound to heal?
Daniel Lobell: (40:20)
No, I think I read an article at some point that somebody was going to have to have their foot amputated and the dog licking and licking it for hours was able to re-stimulate something in the foot and prevent the person from having to have it amputated.
Dr. David Armstrong: (40:35)
Well, look, I’m not going to be on this podcast and advise people to have their dog lick their wounds, but what I will tell you is that it’s long been known that the human mouth is often more microbiologically dangerous in terms of getting an infection than a dog’s mouth in some cases. However, I think it depends on the dog and depends on the human. But there have been folks that have talked about growth factors on the tongue of humans and of other animals. So that could play a role in what you’re talking about. I’ll tell you something else. Dogs have been great for identifying – and this sounds crazy – but for identifying low blood sugar, hypoglycemia in patients because they apparently have a sense and whether that is a sense of smell or a sense of something that they’re about to have a potentially deadly hypoglycemic attack. And dogs have been effective in identifying bladder cancer. Bladder cancer! And it sounds wacky, but you know I’ve long ago learned not to make fun of wacky, lest I make fun of myself, which is really kind of a daily thing with me – knowing the extent of my incompetence. But, hey – want to talk about another kind of animal or sort of insect thing? Maggots. Here’s something for you. So larvae, or maggot debridement therapy, has long been a thing and there are data from our group and from others to show that you can use maggots. You can buy them now from some places in the United States and they come sterile. You apply them onto the wound and they can actually clean up a wound pretty well. And some years ago, you could look it up. I don’t know where it is. I think it’s on YouTube somewhere. We actually had Nat Geo follow us around in clinic and some of our patients for a good week, talking about that because it really is a thing. So that’s a possibility. So you want to talk about the old and the new, that still exists and it can be useful in some circumstances, just FYI. Yeah, they are.
Daniel Lobell: (43:23)
That’s pretty amazing.
Dr. David Armstrong: (43:25)
Yeah. There you are.
Daniel Lobell: (43:26)
You’ve received a lot of awards. I know you mentioned that you were in Nat Geo, which is pretty cool. You were also recognized for your work in podiatric surgery and you were the youngest person ever to be the recipient of the ADA’s–
Dr. David Armstrong: (43:39)
Daniel Lobell: (43:39)
Right? You’re laughing. Why?
Dr. David Armstrong: (43:43)
Oh, I’m just laughing because you’re reading… I don’t know where you got… did I send something to you? I don’t even know. This is great. Well, thank you. Yeah. That was the Roger Pecorero Award from the American Diabetes Association, thank you.
Daniel Lobell: (43:55)
And that’s the highest award given in the field, correct?
Dr. David Armstrong: (43:56)
Well, thank you. Yeah, it’s the highest award given at the American Diabetes Association for something that is the lowest thing on the body in the foot. But yeah, look, I grew up with this, taking care of these patients and I’ve had pretty much everything given to me. So I’ve had absolutely no excuses, but to try to pay it forward. And I know that sounds ridiculous. Kind of now that I’m listening to myself saying this–
Daniel Lobell: (44:30)
–You’re like the Mozart of podiatric medicine.
Dr. David Armstrong: (44:32)
Oh, wait, no, how about Toe-zart? [Laughs] Is that a thing?
Daniel Lobell: (44:34)
Dr. David Armstrong: (44:38)
But no, I am not. If I’m Toe-zart then you would be Salieri.
Daniel Lobell: (44:39)
Dr. David Armstrong: (44:42)
Ooh, G-d. No, I don’t think that would even be a thing. I don’t think that I’m much of a – I did start young, but I wouldn’t call myself a–
Daniel Lobell: (44:53)
A child foot prodigy?
Dr. David Armstrong: (44:53)
[Laughs] If anything, I’m more of a prodigal son.
Daniel Lobell: (45:04)
Or a pod–
Dr. David Armstrong: (45:04)
Podigal! Nicely done, you did that.
Daniel Lobell: (45:04)
Thank you. You were a Podiatric Medicine Hall of Famer, correct? In 2008?
Dr. David Armstrong: (45:18)
Yep, there’s that. That was great.
Daniel Lobell: (45:18)
So you have all these wonderful accolades. What do you think it is about you that makes you such an outstanding doctor?
Dr. David Armstrong: (45:26)
Well, my pop used to tell me – and I’m sure this is on a poster somewhere, but he was the first person to tell me this, that folks don’t care how much you know until they know how much you care. I saw that in him. I think sometimes people know when you’re dialing it in and people know when you really care about something. And, look, I’ve been so lucky to find an area where we can try to make a difference. And, as I said, it’s a team sport and I feel so lucky to play on the team every day. And that part probably shows and it transcends my incompetence. How’s that? [Laughs]
Daniel Lobell: (46:19)
I think what your dad said is pretty profound there.
Dr. David Armstrong: (46:24)
Well, there you are. I would tend to agree, there you are.
Daniel Lobell: (46:29)
So, let’s bring it into Doctorpedia for a minute. What is your view on the online health space? Do you encourage or discourage people to look for (or patients to look for) things online?
Dr. David Armstrong: (46:44)
Oh, thanks for asking. You know, I hear a lot of my colleagues (and these are good friends of mine) talking negatively about you know, Dr. Google or something like that. But G-d knows, I love it! Do I spend a lot of time in clinic talking to patients about good advice and bad advice they might find online? Sure. But is that better than having no conversation at all? Absolutely. So, I think frankly, the more the merrier. And I know many of my colleagues would probably disagree with me, but I don’t know if you can overdose on this. I mean, I think of course you could probably just make yourself so worried by looking something up, so I’d say that’s probably possible. But if you want to go get informed? Have at it, I think that’s great. And the ability now to communicate with my patients as a family is just better than ever. I’m having virtual conversations with patients literally all over the world all the time now. And that – the ability to cut through a lot of stuff is – is so great because you can help connect people and you can help give advice so quickly now, even if that advice is to just go get to see a doctor locally, you know?
Daniel Lobell: (48:26)
Dr. David Armstrong: (48:26)
And that’s very often the advice because sometimes it’s hard to figure something out from a distance, but sometimes it’s not. Sometimes you can give some of that advice locally. So to make a short story long, my answer to you is: yes.
Daniel Lobell: (48:42)
“Yes.” [Laughs] This goes a little off topic, but something I wanted to ask you earlier and forgot to get to. You’ve done so much research and I’m curious, out of everything that you’ve looked up, what would you say is the single most prominent outcome of your research?
Dr. David Armstrong: (49:02)
Wow, maybe a couple of things? First, a lot of the work that we’ve done, now this is over a generation, a lot of the work that we’ve done in trying to create a common language by which many different doctors and nurses and patients can discuss this. So we’ve worked really hard on different kinds of ways to communicate and classifications to help identify that. So that’s kind of one area, to a second thing, which would be to standardize the way a lot of these patients are treated from simple things that are not so simple. Like how to surgically clean up the wound to how to protect the wound all the way out to the optimal way to put teams together and marry those teams with really fancy and not so fancy technology. So those are, if you want to talk about the kind of three pillars. I mean there’s been a lot of other stuff and every day, there’s something new, but you could probably fit it into one of those three things.
Daniel Lobell: (50:18)
Huh. I could ask you a whole interview on any one of those things probably.
Dr. David Armstrong: (50:24)
Oh yeah. Next time, how about wearable robots? Because that’s a whole thing. We have been really active in that area. There’s a wearable robot association and we envisage a whole area where people could be helping to get around their house with a robot. It sounds crazy, but that’s a whole other discussion. Hopefully next week we’ll be meeting with some friends of ours at Cal Tech who are working in this bipedal robot lab. I mean, there’s so many cool things going on. So you see in this weird area in the foot, it’s so rich. So anyway, there you go.
Daniel Lobell: (51:00)
What about fungus? Do you deal with a lot of fungus?
Dr. David Armstrong: (51:04)
[Laughs] Yeah, I guess. I guess we do, thank you. From wearable robots to fungus. We do actually and in fact it’s ubiquitous. It’s among us, if you will. That was bad and I’m sorry I even did that.
Daniel Lobell: (51:21)
It’s okay. We were already in so deep that it’s– [Laughs]
Dr. David Armstrong: (51:24)
–Oh man, that was horrible. I hope my mom doesn’t hear that.
Daniel Lobell: (51:31)
You stuck your foot in it!
Dr. David Armstrong (51:31)
[Laughs] Yeah. So, yes fungus is kind of ubiquitous in so many patients, especially with diabetes. It’s really slow to treat but there are a lot of treatments for it now. One of the important things I would say is go to see your foot doctor or your dermatologist because there are, like I said, there are therapies and they’re not just therapies. You take like a pill, there are things you can actually brush on and rub on now that might be effective in that area. But sometimes it can take so long to treat some of these things because the fungi themselves are so slow growing. It’s like watching grass grow.
Daniel Lobell: (52:20)
Yeah. You know–
Dr. David Armstrong: (52:22)
–Except it’s slower!
Daniel Lobell: (52:22)
Slower than grass – it’s like watching mushrooms grow, maybe?
Dr. David Armstrong: (52:29)
Oh yeah. Nicely done. Really nicely done.
Daniel Lobell: (52:33)
To bring it personal. I’ve got some kind of a toenail fungus going on for many years, which makes my big toe very difficult to cut the nail. And I went to a foot doctor and he put me on some kind of pills that I had to take for a long time and they did blood tests.
Dr. David Armstrong: (52:52)
Right! How did that work? Did it work well or not?
Daniel Lobell: (52:55)
Nothing at all.
Dr. David Armstrong: (52:56)
I’m sorry to hear that.
Daniel Lobell: (52:59)
Finally someone consoles me.
Dr. David Armstrong: (52:59)
Sometimes you have to combine the therapy you take by mouth with local therapy to trim that nail and kind of reduce what we call the fungal load in the area. I don’t know what fungi call it but we call it the fungal load.
Daniel Lobell: (53:20)
Yeah. How do these things attach themselves to you?
Dr. David Armstrong: (53:25)
That’s a great question. The short answer is: I don’t know. The long answer is that there appears to be – believe it or not – a genetic predisposition to getting it in your nail or on your feet. But it’s not your fault. It’s not like you’re like somehow in an unclean environment or something like that. There’s nothing you’re doing wrong, most likely.
Daniel Lobell: (53:56)
Dr. David Armstrong: (53:56)
I mean, it’s very possible. It’s very possible, I’ll say, that you are doing something wrong.
Daniel Lobell: (54:01)
Dr. David Armstrong: (54:01)
But I’m not going to cast aspersions or judgment. But truly, though, it’s likely that it’s not like there’s some sort of unclean environment or you have to wear sandals. But if you are, you know, in a lot of public areas, it’s probably best to do that if you can, but I don’t think that that’s going to totally eradicate fungi on your feet or your nails. And I don’t think there are any data to support that. What I would say is I think you are genetically predisposed to that. Also some kinds of repetitive stress on the nail? I don’t mean like emotional stress, but I mean like stress to the nail like in your shoe or in other areas like that could likely damage the nail and maybe make it more predisposed in one way or another to getting some kind of fungi to deposit in an area. Same thing with the skin. But all of that is supposition. There really are no data to guide us on those things. Remarkably.
Daniel Lobell: (55:06)
Interesting. So in other words, we don’t know. [Laughs]
Dr. David Armstrong: (55:14)
[Laughs] I’ll just put it this way, how about: I don’t know. That makes me feel much better. There’s likely someone, and it’s likely one of my friends, they can probably give you a whole dissertation on this.
Daniel Lobell: (55:24)
Yeah. Well I’ll have to start talking to friends of yours soon.
Dr. David Armstrong: (55:28)
Daniel Lobell: (55:30)
We’ve got to get to the bottom of this thing.
Dr. David Armstrong: (55:33)
Touché. Toe-ché! [Laughs] I apologize.
Daniel Lobell: (55:33)
[Laughs] That’s all right. You know, here at Doctorpedia, we’re trying to assist the online health space and you have videos featured on Ulcerpedia.com which is really the big time.
Dr. David Armstrong: (55:55)
Oh wow. I didn’t even know, so there you go.
Daniel Lobell: (55:58)
Yeah. Well, it’s a very cool place and I encourage people to check it out, check out Ulcerpedia.com and check out Dr. Armstrong’s videos. And you also have videos on YouTube, including a fascinating TED talk that I enjoyed watching part of before we spoke, titled “A Visit To The Human App Store.
Dr. David Armstrong: (56:19)
Wow, look at that! Thank you for that. I appreciate that. Yeah. I haven’t looked at that in a while, but there we are.
Daniel Lobell: (56:23)
Yeah, it’s very cool. And I like the dinosaurs projected behind you as well. If you throw dinosaurs into a TED talk, you’ve got me.
Dr. David Armstrong: (56:35)
[Laughs] Well, you had me at Brontosaurus.
Daniel Lobell: (56:40)
So I want to ask you this: In closing, as we wrap here, what ways do you think that the medium of videos online can help patients?
Dr. David Armstrong: (56:51)
Oh yeah. You hear that a picture is worth a thousand words? Well, maybe a video is worth 10,000 or 100,000. And it just scales up. I think many of us are visual creatures in a lot of ways and if we can get that medium, through that mechanism, then all the better. And you could write it down on paper but seeing it visually I think is really, really helpful. And I think I’m probably preaching to the choir when I talk to you about that.
Daniel Lobell: (57:27)
Well, yeah. But it’s good for people out there to hear about it, I think, and, and to hear about it from a man such as yourself, with such high esteem, who’s really gotten a foot in the door in what he does. Huh?
Dr. David Armstrong: (57:43)
LobellThanks man. That was cicely done. I appreciate that. Yeah, definitely. Listen, you’re going to go far as well. You’ve done spectacularly. You’re now a member – I will go as far as to say you’re like one of the godfathers of sole.
Daniel Lobell: (58:05)
[Laughs] Thank you. Well played. Well played. Thank you so much, Dr. Armstrong.
Dr. David Armstrong: (58:13)
Daniel Lobell: (58:14)
My soul brother from the interview, it was really fascinating and I learned a ton from just talking to you today.
Dr. David Armstrong: (58:20)
Thank you. Not at all, man. This was super fun. Real total pleasure.
Dr. David Armstrong: (58:25)
I’m going to go run five miles now.
Dr. David Armstrong: (58:28)
G-d bless you man. That will make one of us. [Laughs]
Daniel Lobell: (58:30)
[Laughs] I’ve got to, I’m inspired to after this talk. I’ve got to keep moving for sure. Thanks and enjoy not cutting any feed off today.
Dr. David Armstrong: (58:42)
Thanks a million. Now I’m going straight into a research meeting now about that gene therapy thing. So there you go.
Daniel Lobell: (58:48)
Well, I have a few guys named Gene I could always recommend to you guys if you need them.
Dr. David Armstrong: (58:52)
As things progress, I will call on you.
Daniel Lobell: (58:56)
You, will you take Eugenes also or is that too far of a stretch?
Dr. David Armstrong: (58:59)
Well, yeah, the Eugene is too difficult because it’s a little bit too much of those eugenics. [Laughs].
Daniel Lobell: (59:04)
Dr. David Armstrong: (59:15)
Wow. Oh man. Okay. Feel free to use that. Yeah, you’ll have no way to use that but there you go, work it in. This has been a total pleasure, for sure.
Daniel Lobell: (59:21)
Thank you. You know what they say, when it comes to these gene therapies, they say they just get Wilder and Wilder.
Dr. David Armstrong: (59:37)
[Laughs] Oh wow. That is absolutely great.
Daniel Lobell: (59:41)
[Laughs] Thank you.
Dr. David Armstrong: (59:41)
Take care. Goodbye, man.