Beyond Phantom Limb Pain. Max Ortiz Catalan on Human Resilience and Recovery.

00:00:00: phantom limb pain, because as a double amputee that is something I experience every day to varying levels.

00:00:06: Level one would be you feel like an elastic band wrapped around your limb and the sensation of numbness almost like ants are crawling under your skin.

00:00:17: so it's something all the time.

00:00:19: Level two would be like holding your non-existing hand into the fire and you're holding these hot coals, level three is probably the most uncomfortable one.

00:00:30: it's like electric shocks every thirty seconds I get a zap that is so strong that i scream out loud... It sometimes feels like having a knife stuck in to your foot or on.

00:00:49: So today's guest is someone who has spent his career exploring one of the most fascinating questions in science and medicine.

00:00:57: What happens when technology becomes part of us?

00:01:01: Professor Max Ortes-Catalán, is one of world leading experts in bionics neuro rehabilitation and phantom limb pain.

00:01:10: His pioneering work has helped create some of the first prosthetic systems that connect directly to muscles, nerves and bones.

00:01:18: Allowing people to control bionic limbs more naturally – even regain aspects of sensation!

00:01:25: His research has been published in one of the world's most prestigious scientific journals….

00:01:30: …and his innovations have changed the lives of people living with limb loss around a

00:01:35: globe.".

00:01:36: But what makes Max particularly interesting is that he isn't just a scientist, but also humanitarian.

00:01:45: Today he's heavily involved in rehabilitation efforts in Ukraine helping people rebuild their lives after devastating injuries and trauma.

00:01:53: As someone whose own life was transformed by prosthetic technology I'm excited to explore not only the science behind bionics in a world where technology is increasingly becoming part of our bodies, our identities and perhaps even our future.

00:02:10: So welcome Max to the cool!

00:02:13: I seem to think that you're joining us from the Ukraine itself?

00:02:17: Is that right?

00:02:19: Correct.

00:02:19: yeah i'm in Kyiv at the moment.

00:02:22: how are you doing?

00:02:24: well i'm doing fine many others or not.

00:02:27: last night was heavy.

00:02:29: there were attacks the whole night.

00:02:31: And it's been like that for the past couple of weeks, so unfortunately the conflict has not de-escalated.

00:02:39: everything seems to indicate this is going to escalate now already and in the coming days.

00:02:45: but I am okay.

00:02:50: you're in a safe place, you have access to the internet.

00:02:53: I'm very grateful that we can have this conversation so i just hope that the connection will last for the length of our conversation but i do really appreciate.

00:03:01: um...to get your views let me just take you back for a second here and before we start talking about bionics i would love to know a little bit more about your career history and what actually drove you to wanting to work in this field.

00:03:20: I can imagine that you were perhaps the child who took things apart to see how they worked before putting them back together.

00:03:26: Am i wrong?

00:03:27: Yeah, sort of.

00:03:29: I knew it!

00:03:31: No...I started my career as an electronic engineer so that's what I studied for my bachelor's.

00:03:38: That was actually between psychology and engineering but at the end I realized I did electronics because i like to see things moving.

00:03:53: And then, I worked for a manufacturing industry for couple of years with robots and production lines... ...and the technology level was as expected but ultimate goal that companies were working on it wasn't feeling what they wanted me do for my life.

00:04:15: So after a couple of years I quit and decided to go back to school, then i became interested in science.

00:04:22: interestingly...I didn't care much about science until after I graduated.

00:04:26: that was the real world working than I become more fascinated by it.

00:04:33: so Then I moved To Sweden where did masters in complex adaptive systems which is part them applied physics department and there I learned more about dynamical systems, AI chaos theory stuff like that.

00:04:52: When the time came to do my masters it felt as if they wanted me in medicine because i had a feeling of being fulfilled working on this field which is how we end up in prosthetics.

00:05:04: so with background electronics and algorithms and actuators prosthetics was sort of like a very nice application, not only interesting for where it gets to the people but for my background.

00:05:23: Was there any specific moment that changed direction in your career?

00:05:29: I don't know.

00:05:30: is there story about patient you've met or an inspiration from somebody who has lost their limbs?

00:05:37: No,

00:05:40: not directly.

00:05:40: I started working on prosthetics because I felt like...I was in Gothenburg and Sweden at the time.

00:05:48: Post-integration still remains a big field.

00:05:51: so it's discovering Gothenborg.

00:05:53: So i happened to be here where post integration which is basically what happens if you put titanium into bone Bone grows strongly around.

00:06:02: that so makes strong mechanical attachment.

00:06:05: before if you normally put a foreign material into the body, then it will see us as not belonging in there and try to either destroy or push away.

00:06:16: And that doesn't happen with titanium monosauce.

00:06:19: so that was big discovery at time.

00:06:21: So there is lot of research going on in this field.

00:06:27: I happened have background which would be suitable for using to take it beyond a mechanical connection, but also you can say communication with the neuromuscular system and control systems of the prosthesis.

00:06:43: So sort I entered in field because my background what happened is probably biggest realization impact of amputations that i had working patients was more related to phantom limb pain which I start working sort of in parallel after a couple years that I was working on prosthetics.

00:07:08: When I was developing the control systems for the prosthesis, um...I had volunteers who would come to the lab uh..to help me test this system and with one of them when i was speaking about the development of these new implant technology they will give better prostheses he told my look I'm retired more than half life without an arm, this arm which was a body power attached with the leather sort of socket very relatively old compared to technologies that were available at the time.

00:07:44: He's like.

00:07:44: well you know these does do job but what really is bothering me?

00:07:50: pain.

00:07:51: and then I learned about phantom limb pain from the direct experience of a patient, and I could see how that played a big role in his life to the point where the amputation itself was bothering him less than pain because when you're in pain it jumps in priority.

00:08:08: And those things were what shaped the direction.

00:08:15: Yeah,

00:08:17: because you mentioned like some of the topics that I'm hoping to take a deeper dive on.

00:08:23: So osteointegration definitely something that i am keen to understand bit more... The way that I understand it is very similar to having a dental implant right?

00:08:33: It's its same principle but a lot more complicated I imagine.

00:08:39: And the other topic that i wanted to hear your thoughts on is about phantom limb pain because as a double amputee, that it's something that I experience every day and at two varying levels as well.

00:08:53: so...I have pain that comes in levels!

00:08:56: So level one would be you feel like you have an elastic band wrapped around of numbness and almost like ants are crawling under your skin, so that is something I experience all the time.

00:09:12: Then level two would be holding you hand into a fire – your non-existing hand in to the fire–and you're holding these hot coals… That's intense burning sensation!

00:09:25: And then Level three is probably the most uncomfortable one... Luckily it doesn't happen too often but electric shocks.

00:09:34: It's almost every thirty seconds I get a zap that is so strong, and then I scream out loud.

00:09:41: it sometimes feels like having a knife stuck into your foot or in you hand.

00:09:48: So its really strange And i always try to explain this to people.

00:09:53: A lot of people are aware about this phantom limb pain But no one really knows what it is and can be done about.

00:10:02: I try to explain that your brain doesn't understand something's missing, but keeps sending out signals at the end of a limb which makes half way.

00:10:16: Then comes back into the brain saying there was a hand or foot missing here so it must hurt!

00:10:25: And so the brain reacts like that and sends out the pain signals to match it.

00:10:29: But, that's my very unscientific interpretation of it!

00:10:32: I have no idea if actually is true in any remote sensation….

00:10:37: So perhaps you can enlighten me a little bit about what phantom limb pain is –in the science aspect?

00:10:44: Right... You're touching many different aspects on phantom-limb pain difficult viewpoint, and so difficult to treat.

00:10:57: And sort of like overcome from the clinical side.

00:11:02: pain is a complex experience.

00:11:04: it's made out of physiological and psychological factors.

00:11:08: So things that come you know from your body The way it works and then how do you react?

00:11:17: It's very unfortunate That we are less sympathetic to conditions that we don't understand.

00:11:24: So if you see somebody walking and they fall, or they break a leg... Or they have like a cut or something You can understand the pain And then people tend to be more sympathetic.

00:11:35: But If you tell someone Okay well I've had pain in part of my body That no longer is there Depending on how educated are their condition.

00:11:43: There might be less sympathy And it's related with your family Your spouse co-workers, your working environment.

00:11:52: So there are unfortunately lack of education and awareness on the condition.

00:12:00: one of them issues.

00:12:02: sometimes this varies.

00:12:03: so I travel around the world and discusses it can see heavy cultural differences how people perceive depending their culture.

00:12:13: some cultures particularly men they have to just tolerate pain and not talk much about it, whether or in others is less.

00:12:23: Their relationship of respect with their doctors will also dictate how comfortable they are speaking about it.

00:12:30: so education is one of the missing links on... Just allowing people to open up and talk about their pain and speak with clinicians that can help them.

00:12:47: that's sort of like the cultural situation and societal situations with pain.

00:12:52: Then we have, you know what is pain?

00:12:55: Pain is normally in an unable body on a healthy system.

00:12:59: it's an alarm... It's an alert system.

00:13:01: if you cut yourself or burn yourself send signals to your brain.

00:13:05: We have sensors in the periphery That sends signals related The brain potential damage On whatever that sensor is connected.

00:13:13: right something very interesting about The sensory system works, and this is also interesting for prosthetics.

00:13:21: We have sensors around our hands and legs And those are connected.

00:13:25: They they have a connection you know with the bit of wiring to the brain?

00:13:29: That's how your brain knows that you're touching an object.

00:13:33: If it has different temperatures You will feel different temperatures and if you cut yourself It would say well there is potential tissue damage in that area.

00:13:42: So when do lose their limb The sensors that used to be connected with that part of the body if you stimulate those nerves and If you stimulate Nerves, they're just a convey touch.

00:13:55: That person will feel sensations coming from their phantom.

00:13:59: And now when you put up prosthesis in this space occupied by the phantom is not by the prosthesis patients perceive Sensations coming from the prostheses and that's automatic.

00:14:08: You know if your your hand, if you touch anything.

00:14:12: You don't think I want to feel...you just feel it appears in consciousness without you making any effort.

00:14:17: that's very useful for developing prosthetics that can feel and that some of the work that i done with with implanted electrodes in the nerves that provide sensations where they comes to pain.

00:14:27: also when those pain these those fibers technically there are not pain fibers because pain happens in the brain.

00:14:35: but those sensors the brain will create painful sensations in the missing limb.

00:14:43: And that's what we know as phantom limb pain, so... Phantom limb pain is the experience of painful sensations In part of the body-in the limb for phantom leg pain.

00:14:52: but it also happens if you have an amputated nose or ear Breast after a mastectomy.

00:15:00: It happens around the body But in our case where more familiar with extremities people with amputations will experience it.

00:15:12: In epidemiological studies that have been done since the eighties, their prevalence of phantom limb pain is above sixty percent and this in across the world.

00:15:23: This is in the north or south east west Europe Asia America.

00:15:29: The incidence and prevalence of Phantom limb pain It's about same.

00:15:32: So we know it.

00:15:34: a real condition And one thing which tried to educate them the population about, so it is normal.

00:15:43: Most people will experience it but fortunately now there are few methods that allow to treat and potentially prevent them.

00:15:50: So thats where we're on sort of like... The understanding of the condition itself.

00:15:56: Now why does this happen?

00:15:59: Thats a very interesting story because historically In the same way that you created a theory about why you think phantom limb pain happens, we all do the same.

00:16:13: You know and doctors and scientists will do the saying based on their understanding of the body.

00:16:17: at the time One of the

00:16:19: most

00:16:21: known ideas not only in the public but in the scientific literature is there are certain changes in them in the cortex of the brain because those were correlated to the princess or Phantom limb pain.

00:16:35: however that was always a correlation and there were no causal relationship.

00:16:41: And we know, as I said before the brain will make you experience sensations in your body.

00:16:49: pain is embodied.

00:16:51: That means that pain cannot exist floating around Pain.

00:16:54: it's always somewhere inside of your body.

00:16:57: so your brain has to localize it somewhere.

00:17:03: So for long time circuitry, or the capacity to do that.

00:17:10: And for many years there was this idea of changes in ways things are localized will create pain.

00:17:17: but it turns out why we

00:17:20: know

00:17:21: is because Painfield a famous neurosurgeon was doing surgery in the brain and will stimulate parts of the brain.

00:17:29: And then patients would say, well I feel that you're touching my hand or your touch on my foot are you touching my elbow?

00:17:35: Then it sort-of made a map Of The Body On How It's Represented In.

00:17:39: The Brain Is Called A Homunculus.

00:17:42: If You Google It You Will See This Mostly A Man.

00:17:45: It Was Mostly The

00:17:46: One With The Hand Where You See Big Hands

00:17:50: The Big Leaps Small Torso That is Proportional To The Area that is using the brain to localize sensations.

00:18:00: So it's very interesting and many neuroscientists will have like a sculpture somewhere in their office, The thing is during this process of mapping there was rarely patient-reported pain.

00:18:14: so one question I posed for my community since a couple years now if its hard from the cortex where we are mapping things, were there been observations of changes.

00:18:31: How is it that those changes create pain?

00:18:34: So that link between the genesis of pain and changes on the cortex has never really established.

00:18:42: so I realized this was a problem when i tried to understand phantom limb pain out-of-the treatments positive results and just became very curious, why are we getting positive results in patients that didn't show an improvement with other therapies?

00:19:02: And then I started examining what we knew.

00:19:04: That was the standard sort of like explanations...I think now there is enough evidence to say it doesn't seem to be the case.

00:19:13: Another interesting aspect but you described sometimes feels like burning something.

00:19:18: if it's electric sometimes common anesthesia, what makes it?

00:19:23: why so much variability?

00:19:26: In first place you... It's very difficult for your brain to create the novel experiences.

00:19:32: To create experiences that we don't have hardware for So phantom limb pain is described as how you will describe damage to a limb.

00:19:44: Cots burns.

00:19:47: There are normally not the scriptos that you are not able to experience on your other hand or in your other leg, right?

00:19:55: So so the brain has The capacity to process their experience because there are sensors about it.

00:20:01: And the question is how?

00:20:03: Why is it burning sometimes and why is he choking some times?

00:20:06: I'm with cotton sometime's and It seems to me that that's rather random.

00:20:14: one of the things That we know about the brain is that it doesn't behave like a computer.

00:20:19: So in a computer we know exactly what will happen when you push a key because everything is deterministic.

00:20:25: We know input, output...we know it's going to happen.

00:20:29: The brain works with a bit of noise.

00:20:32: Many complex systems have noise as part the way they work.

00:20:36: To make them more resilient or false.

00:20:41: There are certain noises on their brains.

00:20:45: Because my background and dynamic system looking systems, I realized that it takes us years to learn how use our hands.

00:20:56: In the first year of life we're pretty useless you know?

00:20:59: We have to learn about walking and using our hand and manipulating things.

00:21:04: That means... It take some time for us to develop this circuitry which allows all these things And a lot of neurons in your brain control your limbs.

00:21:20: When that limb goes away, all those neurons sort of lose their job.

00:21:24: But they cannot be entirely silenced.

00:21:27: So if you have no activity here and full activity this is I'm moving around i can feel with My motor system is doing movement And my limb is sending information always about what it is.

00:21:40: because If you close your eyes You know What Is Your Thumb?

00:21:48: So that's information is always coming to the brain.

00:21:50: But so, the limb goes down considerably and because there are these random activations when the activity is high those random activation they won't cause really any problems.

00:22:03: but when it is low then my trigger pain because of the pain processing circuitry for sensations and control their work together as a brain has to localize pain.

00:22:18: One way, you know I've been trying to explain this in ways that are a little bit easier.

00:22:22: but You can think about these cocktail party example where you go to a party everybody's talking.

00:22:30: You say something silly.

00:22:31: Maybe it doesn't matter because nobody listen cuz everybody was on the speaking and then sometimes you will Say something silly for some reason.

00:22:39: Everybody shut up And then everybody listens.

00:22:41: It's happened to me before!

00:22:43: I know exactly what you mean, the moment you say something silly and everyone is quiet down... Everybody hears you?

00:22:50: Yep totally.

00:22:51: So it's notice like an analogy for what will happen with these random activations.

00:22:56: when activity goes down Then this firing can be noticed or produce pain.

00:23:01: Potentially that why has so different qualities?

00:23:04: because its randomly comes at a different time.

00:23:06: It happens right away after the amputation after, so that's the working hypothesis.

00:23:17: That has many predictions now clinically.

00:23:19: what does it mean?

00:23:20: So if we give those neurons their job back or a job for purpose again and activity goes bad then that noise will not create more problems.

00:23:30: The way we have sort of like try to resolve is exercising their phantom And two of the treatments that I created and the technologies around it is to get patients to exercise their phantom in, do many phantom movements.

00:23:46: So we use virtual reality electromyography AI to infer what this patient trying to do all with a purpose together.

00:23:53: patient to do phantom movement because...

00:23:56: But you know what?

00:23:59: Well every time i put on my bionic arm It seems help with phantom limb pain.

00:24:05: So I noticed that if my brain has a visual, there is an extremity and even though it's not my own hand – it gives me a signal of reassurance in saying its okay!

00:24:17: And I notice that it actually psychologically helps quite a lot.

00:24:21: when the pain is at most severe just having an arm there somehow calms down.

00:24:30: but also a pattern of when the phantom limb pain goes into level three, which is my highest pain threshold.

00:24:38: And it's generally when my nervous system is overstimulated.

00:24:43: so if I'm incredibly nervous about doing something... It almost feels like my body is firing signals all over the place and that's where the phantom limb pain at its worst.

00:24:57: but sorry, enter after due because I'm hoping that you could go into the details as to what solutions you have found to help people with managing their pain levels.

00:25:08: Is your prosthetic... is it a myeliatric arm?

00:25:11: Yes!

00:25:12: Yeah.

00:25:12: so there's a correlation between power prosthetics, myellectric prosthesis and less phantom limb pain.

00:25:20: And if you think about in an electric prosthesis to control it, right?

00:25:26: Maybe you are not using the full extent of that circuitry but part Patients with a cosmetic prosthesis that don't do anything, they report the same amount of pain that patients who have no prosthesis.

00:25:59: So vision alone doesn't seem to be their treatment factor and it is important because the treatments we develop using virtual and augmented reality initially thought was that its vision making this trick on our brain.

00:26:16: but after more deep thinking problematic, the idea that if we think that vision makes an illusion and reduces your pain.

00:26:29: That will mean that the visual system has priority and can override The pain process on system.

00:26:38: And there it can be certain.

00:26:41: you know It can modulate a little bit but not in such way Change it.

00:26:48: so there are a lot of vision illusions in my presentations Are often used one where they're two circles and then little circles around a big circle And one of them looks bigger than the others, and didn't you remove everything?

00:26:58: Around.

00:26:58: They look the same.

00:26:59: You put him back.

00:27:00: this one looks bigger and you can do that hundred times in a day.

00:27:05: As soon as you've removed the things that I'm making delusion you will perceive reality right.

00:27:12: if we think that vision can stop pain That would mean vision, in this case with the vision illusions.

00:27:20: It doesn't even have the capacity to change your perception of the visual system itself like it comes and goes so it does make a permanent change.

00:27:30: So saying that they will make a Permanent change on pain is a bit of an stretch And I think there are lot of ways we try explain.

00:27:39: phantom limb pain has been a little bit of explanations that intuitive But once you go more rigorously and examining them, they don't hold.

00:27:51: And that's been one of the problems with this condition because treatments historically have not had a good theoretical basis.

00:28:01: so... Well I mean when i was in hospital I remember that I was meeting with the pain management team on a regular basis and the answer to controlling the phantom limb pain was medication.

00:28:15: I have to say that it helps in some aspects, but medication is not something you want take for the rest of your life on a daily basis.

00:28:25: because actually... The impression it gave me was that it was masking the pain.

00:28:30: But it wasn't doing anything to resolve it.

00:28:34: so….

00:28:35: I don't know.. Medication isn't my favourite part of this and i'm not taking any medications since a while now And he hasn't really made major difference either.

00:28:48: You talked a little bit about osteointegration at the beginning, and I wondered if by doing the osteo integration you can also improve.

00:29:06: Just to comment on the medication.

00:29:08: Medication is very useful for acute pain, when you are recovering from surgery.

00:29:14: it's a very important tool that should be considered.

00:29:18: The issue is that medications manage their pain as symptoms but not in condition so they will not fix the underlying problem.

00:29:27: Now if we talk about us integration what is the underlying problems?

00:29:30: The underlying problem is gone and there was no sensory input or motor output.

00:29:36: Osteointegration, it's a great technology for mechanical attachment of the prosthesis.

00:29:43: Wait maybe we need to explain what osteointegrations is?

00:29:46: I said in the beginning that they're kind-of similar to having dental implant but more complicated than that right.

00:29:52: so its basically inserting a titanium rod inside your bone or arm.

00:30:05: Yeah, depending on what your level of amputation is.

00:30:08: For

00:30:08: me it's above the elbow basically and then you can attach a clipping method that you can then attach your arm onto.

00:30:21: but its more than that right because you're literally rewiring muscles tendons and nervous connections inside the limb.

00:30:30: I find sensational.

00:30:33: So that's a separate technology.

00:30:35: and what makes prosthetics also hard, amazing at the same time is there are many different aspects about it.

00:30:44: It not only one field that goes involved on making good prosthesis.

00:30:50: so osteointegration is process by which bone cells grow in titanium surface.

00:30:57: isn't titanium oxide but you know technicality and bone cells are going to anchor it.

00:31:05: Originally, the first application was dental implants that were the principle then extra oral.

00:31:11: so there's a very interesting application called the Bone Anchored Heronate for people who lost their inner ear but they're cochlea still functioning.

00:31:21: you can put a screw in this hole and you can vibrate this hole And that will stimulate the cochlear.

00:31:26: and you hear That is based on OSI integration.

00:31:29: That was developed by my PhD supervisor, Professor Bo Hockenson in Sweden where I was doing research.

00:31:39: So after it was used in the face then people noticed that he could be a very good solution for attaching a prosthesis to the limbs because conventional way is a socket and you're familiar with a socket people that might not know, it's a device that compresses the residual limb to create enough suspension for the prosthesis.

00:32:03: And sometimes... It has a lot

00:32:04: of advantages but also have a few disadvantages like the socket needs to be fitted perfectly with your residual limb and there is an issue about heat as well which generates heat because materials are non-braveable.

00:32:22: so there are advantages or disadvantages in the socket you're right?

00:32:26: But also what I noticed is that if you don't have an elbow, like for me it's impossible.

00:32:31: I do not have osteointegration but for example with the socket its possible to lift my arm above your head?

00:32:46: So thats exactly a video we show our patients because they know this problem and that takes us into another part.

00:32:53: so if you have osteointegration and you have electrodes to control the prosthesis on this skin.

00:33:00: You can lift their arm, but if you lift it above your shoulder then the prostheses doesn't work anymore because activity of these shoulder muscles will activate the prosthesis.

00:33:10: And that's part I was talking about related to controls.

00:33:14: So also integration allows us a very good mechanical attachment so we are free in our adjacent joint But it does not allow you to control.

00:33:23: The control is a little bit better because you can feel more of something called osteoporception.

00:33:30: So patients with an osintegrated implant in the lower limbs, they can tell if they're walking on grass or sand or cement or a carpet... Because tiny vibrations go to their bone and that is their sense by mechanoreceptors basically conferring formation into the brain via nerves.

00:33:54: And you tell me how technical, do want to go?

00:33:56: But some of the research we did is that osteoporception actually not only touch conducted by nerves through brain it's also sound.

00:34:06: so when particularly on their arms and with done experiments where can put a vibrator vibrating at music frequency or any song patients listen vibrate in their implant, because the mechanical waves will travel on the humerus.

00:34:24: They'll get through all of these joints to stimulate the cochlea.

00:34:29: So it's a combination between feeling and hearing that you get this additional sensory input when you have a titanium implant.

00:34:40: Now if we talk about phantom limb pain they give us more information but seems not enough to reduce phantom limb pain, at least the incidence of phantom leg pain is the same whether you have a socket or an osintegrated implant.

00:34:54: What's different... So when I entered the prosthetic field in Sweden, osintegration was established and patients had had an implant for over twenty years.

00:35:07: it was sort-of like i would say an established field although people still even today they call it as a new technology.

00:35:15: It's been around for some decades, but when I enter the knowledge about us integration and how to put an implant that gonna have prosthesis was sort of established.

00:35:24: My contribution to the field was to take that mechanical interface and re-engineer it so we can put electrodes in there some muscles So we can control the prosthesis and provide sensations.

00:35:38: What?

00:35:38: what i did?

00:35:39: Was basically leave intact all the external parts of the implant, so how does surgery is done?

00:35:47: What are their materials that touch in tissues.

00:35:49: So I don't disturb anything.

00:35:51: we know work but re-engineer what's inside it and basically use as USB C to the nervous system.

00:36:02: When patient connects prosthesis gets mechanical connection.

00:36:05: also electrical connections to electrodes with pieces of metal connect, there are plays close to the nerves and muscles.

00:36:14: So when a patient tries to do movement we capture that electrical activity goes into the implant.

00:36:19: We have an embedded system electronics that amplify it And AI algorithm that understands them then tell the prosthesis what they're doing.

00:36:27: When the prostheses with sensors interact with an object touches an object we send signals to electrodes that place in their nerves provide sensations.

00:36:40: And the sensations are mostly tactile, so touch.

00:36:43: they're very rough at low levels.

00:36:47: it does feel like their patients will describe them as indenting the skin with a pen you slightly.

00:36:54: yeah if we make it stronger then start to feel electric and then its spreads on area is not uncomfortable or painful.

00:37:05: But it's certainly not natural.

00:37:07: and we try many different, you know We have a bunch of papers on how we stimulate the nerves And we can use different protocols and so on to try to produce something that is perceived as natural.

00:37:16: but we Have a fundamental limitation.

00:37:20: That is the number of connections we can have with the Nerves or the axons within the nerve?

00:37:28: And that's an open problem that has to be resolved and it is the resolution of the neural interface, meaning to how many individual accents of neurons we can connect so that we can stimulate or record if you want provide sensation.

00:37:48: So my work was on developing a system that self-contained everything in the prosthesis for patients safely and independently in daily life.

00:38:05: And then the other part were on phantom limb pain.

00:38:08: You said in the beginning that this is no longer, in your view considered a new technology?

00:38:13: I mean it's been implemented in Sweden.

00:38:17: as if you have an accident similar to mine... ...you would get an osteo-integrated connector straight away.

00:38:29: not by default though.

00:38:31: No,

00:38:32: not by default.

00:38:35: It's normally.

00:38:36: they will try to use a socket first and then if there are problems with the socket because you know it is more complex and so on... There would be an evaluation but then if the multidisciplinary team decides that you're a suitable candidate than you'll have it But its rather accessible.

00:38:57: I was wondering because it is an option that i have considered, but there were some questions.

00:39:04: It's like one how long does that operation last?

00:39:07: It seems to me that there are a lot of complicated steps to go through in order to get to the final result...I can imagine I don't know if its a fifteen hour surgery type thing or something.

00:39:21: you've got down too short.

00:39:24: So if you are gonna, it depends what you're getting right at the time.

00:39:29: If we only get in us integration that's more shorter In there and they work.

00:39:34: that I've done so Initially would have was integration an electrodes in a patient That had no surgical reconstruction meaning will be using biceps and triceps to control their hand in The same way that you have surface electrodes but instead of being on the outside They were on the inside.

00:39:50: yeah

00:39:51: In order to get more information, to control more joints we start using surgery to rewire the residual limb.

00:39:58: And there are two surgeries that are quite known targeted muscle re-innovation.

00:40:02: That means you take one nerve.

00:40:05: So say the median nerve that controls these fingers at this height is cut because it's not connected with any muscles.

00:40:11: so normally just have an enormous.

00:40:13: The biceps has two heads but don't have a elbow.

00:40:17: so there is no biomechanical purpose for the bicep because it's not actuating a joint.

00:40:22: So what you can do, You can cut the wire that connects to one of the heads or short head of the biceps... ...you have the musculataneous nerves and connect them with both heads... ...and then transfer the median nerve into this head.

00:40:37: When that nerve grows after several months when we think about closing our hand the short-head contracts and when you try to flex the elbow, the long head of the bicep contracts.

00:40:49: So now we have a muscle that will contract differentially depending on what your trying do And then just put an electrode in each head.

00:40:58: Then you can control the open-and-closing of the head.

00:41:00: so with the opening you'll do it with triceps but you've got two functions instead.

00:41:05: one That's targeted muscle renovations.

00:41:09: It is transfer from nerve into a muscle available at the residual limb.

00:41:15: Now, surgeons then thought well you know the median nerve can do all of this.

00:41:20: Why are we transferring just a full nerve into our muscle?

00:41:23: What if?

00:41:23: what if We don't have enough muscles?

00:41:25: so then they start taking pieces Of mussels for somewhere else in the body.

00:41:29: So say the leg.

00:41:31: it's called a free-muscle graph.

00:41:32: You take as more piece of muscle you Take the nerve The median energy split It Into its bundles or fascicles and Then you put that small piece of Muscle In those nerves.

00:41:43: so the nerve will grow innervated piece of muscle.

00:41:46: So later, when you try to do movements these neuromuscular constructs that you build surgically will start contracting.

00:41:53: we put electrodes in those and then use an AI to sort-of understand what they're doing.

00:42:01: so all this is to say it's... To get a prosthesis You can just us integration ,you could get surgical reconstruction .You can get implanted electrodes surface electrodes Then you have a controller top.

00:42:11: There are all different technologies.

00:42:15: it all depends what the level of your injury as well and how that can be best adapted.

00:42:19: Yeah, I mean i would be interested because there sounds to be like so many advantages.

00:42:26: but at the same time does you body always accept this or is doesn't start rejecting?

00:42:32: I mean titanium is accepted by the body.

00:42:36: then I'm thinking if you go for a full rewiring inside your body, and also you have a metal rod coming out at the bottom of your residual limb.

00:42:47: Like how much infection risk is there over the long term?

00:42:53: So many questions

00:42:55: in that... Sorry!

00:42:59: The answer is more likely than not.

00:43:02: just so these surgeries they're mostly successful.

00:43:08: Osintegration is mostly successful, meaning the body will accept it.

00:43:12: Titanium is one of the most highly biocompatible materials—meaning that they produce very little reaction.

00:43:19: Sometimes people are even allergic to gold and... Most people can use gold jewelry because it's very bio-compatible.

00:43:28: but some people are not allergic to Gold —but they can use titanium jewelry cause'it's more

00:43:33: compatible.".

00:43:34: So… To answer your question what what we can do from the scientific viewpoint is to look at studies and look at their rejection or the complications in all of these procedures.

00:43:47: And they're up there with, with the complication rates on most procedures done in medicine so it's not much more dangerous than other technologies.

00:44:00: I think this is fascinating as a as an advancement.

00:44:04: And I've heard you talk about AI several times, part of this procedure.

00:44:13: but can you explain to us how AI helps in the situation?

00:44:18: Is it collecting data and supporting user friendliness because a level of prediction?

00:44:31: or how do we understand the involvement of AI in this?

00:44:35: Yeah, now I use the word AI because it's more recognizable than saying machine learning which is mostly what is used.

00:44:42: So AI has different sort-of like soft fields.

00:44:47: Machine Learning is one of them where a machine learns something and The embedded system, the electronic brain of the prosthesis will learn based on what the patient is trying to do.

00:45:10: So we would, and they way you do it that's your training.

00:45:12: so tell them okay try open their hand then record those signals with machine learning algorithm.

00:45:18: Okay this pattern of electrical activity means opening in a hand.

00:45:22: This pattern means closing hands, this pattern means moving little finger And so does use done primarily when I talk about the way we have used AI.

00:45:33: Of course, there are companies now they're collecting more data and try to analyze how patients using things or trying improve it for control.

00:45:44: that is standard application but of course you know now its use a little bit everywhere.

00:45:48: yeah i mean ive find fascinating.

00:45:50: that helps me understand The machine which is now my bionic arm, it's supported by my biological body and how the connection between human and machine getting better.

00:46:06: Now if we look into future what do you think next twenty years are going to bring?

00:46:10: Are we gonna... ...think or feel that part of our body as a machine is actually integrated with us?

00:46:19: It's part of us!

00:46:20: Are we closer?

00:46:21: because I so far I feel it when i put on my limb or don't have it on.

00:46:27: It's still in mind a tool but not really part of the body, do you think that for twenty years we won't be able to tell difference?

00:46:40: Again there are different aspects to this question and some things you're talking about is normally called embodiment.

00:46:48: so there's a discussion on what does that mean?

00:46:55: And this tend to be, it is not binary sort of like I... It is me.

00:47:01: It is not me.

00:47:02: He tends to be an expert in the spectrum.

00:47:05: and What our patients will say is that you know i feel these as my arm.

00:47:10: This Is My Arm!

00:47:12: You Know its part Of Me.

00:47:14: We did some experiments where we would look at temperature of their residual after an amputation of the residual limb tend to be colder.

00:47:23: Yes, I noticed

00:47:23: that very true.

00:47:25: with my leg.

00:47:26: yeah it always feels a lot cooler than the rest of my body.

00:47:30: Yeah so one explanation is because the way the vascularization now in the residual was affected.

00:47:36: but thats why its colder.

00:47:38: another idea is that the brain realizes there's no leg or arm and then it reduces the metabolic efforts.

00:47:47: Sort of like you're not embodying a prosthesis, that is... You don't have leg.

00:47:52: so then it reduces their efforts there are necessary to maintain them.

00:47:56: and what we have observed with our patients who has host integration in implanted electrodes?

00:48:01: they use the prostheses all the time.

00:48:03: when described as part of body temperature between both arms pretty much same.

00:48:12: We see this as biological marker for embodiment.

00:48:15: The argument here will be that the brain do believe that's part of their body and therefore it normalizes um, the temperature or the metabolic efforts there are needed to maintain their acetylene.

00:48:28: So that-that's a part.

00:48:29: you know how you feel but what our patients would also say is this my arm until it breaks.

00:48:36: yeah something happens very quickly.

00:48:40: The moment that the prosthesis breaks is no longer my arm, you are not embodied it's not part of me and it happens like this.

00:48:47: but it also happens on what you're trying to do.

00:48:50: if your only grasping an object-that's fine!

00:48:53: It's my arm...if you need to use some chopsticks..you know so they....it's very environmental dependent according to their circumstances at which we try to achieve.

00:49:04: because If a task comes that your prosthesis is not, you know allowing to do that then it doesn't feel like yourself anymore.

00:49:15: So so its very variable.

00:49:17: now two...to your question are we gonna fill in twenty years?

00:49:23: I'm not even sure we're going to be here in twenty years the way AI

00:49:26: is developing.

00:49:27: Stop it!

00:49:28: So, so i think by then uh... We probably won't be around or nothing are

00:49:33: present for.

00:49:33: Okay ten years?

00:49:35: Not even ten years..I think they you know.

00:49:37: three-to five that's what most people do.

00:49:38: Oh my gosh don't say

00:49:39: that!!

00:49:41: So if we don't go into that discussion and believe that for a different podcast.... Let's not!

00:49:47: The problems that we have is as I said before their resolution of the human machine interface.

00:49:56: How many neurons can we connect to be able to have full dexterity and provide sensations.

00:50:04: that has reached us as a human experience?

00:50:07: Of touch, temperature and effective touch... That's something amazing about humans or mammals.

00:50:16: from what we know is that we had nerve fibers specialized for effective touch.

00:50:22: They only fire at a certain speed, so they are related to caresses.

00:50:26: that's something very hard to build again with the prosthesis.

00:50:32: So if we were able connect all those fibers then certainly your brain will feel that artificial limb or tentacle whatever it is as part of you body.

00:50:48: We don't have technology today.

00:50:50: we will need to have a completely different material or mechanism, maybe optogenetics.

00:50:58: There has to be something new that allows us to reach high connectivity with the nervous system...

00:51:07: The level of precision would be so-so required to do this.

00:51:12: but there's another aspect that I'm interested in is, you mentioned about the residual limb being cooler than the rest of the body.

00:51:22: Now temperature is something that i thought quite a lot this summer because it was super hot here where im talking to from and we reached like plus forty degrees celsius at some point.

00:51:38: It's a real challenge for me wearing two prosthetics as we talked about the socket that I have.

00:51:43: They are not breathable, they're made out of silicon and titanium in carbon fiber... And one way to cool myself down was think about my next project so planning an expedition.

00:52:06: I want to reach the South Pole, it's about a hundred and eleven kilometers on Nordic skis.

00:52:14: To get to the south pole... And of course you know its rather cold out there at minus forty degrees!

00:52:23: I was wondering how that exterior environment is going effect my residual limbs because.. Is the body clever enough?

00:52:34: Okay, this is a really harsh cold environment.

00:52:37: I need to pump enough blood through all of the limbs functioning to keep them

00:52:43: warm.".

00:52:44: What do you think?

00:52:46: Aside from the fact that it's rather crazy idea in first place...I do realise that!

00:52:51: But i'm quite excited about discovering how my body reacts to this as an MPT.

00:52:58: So am not expert physiologist but my understanding The body normally does the opposite.

00:53:05: So it will try to bring blood in, preserve core functions and keep you alive.

00:53:12: That's why amputations by frostbite can happen.

00:53:21: It is smart from a viewpoint that it evolved trying to preserve what more important.

00:53:28: I'm not entirely sure how are going experience?

00:53:33: Good luck, sounds exciting though.

00:53:37: It is definitely something that's a little bit out of the ordinary but reality.

00:53:43: it like you can only improve technology and medical devices if individuals are testing different types of environments, right?

00:53:56: So the whole plan for this expedition is our mission to collect data as how bodies react in that harsh environment.

00:54:05: I'm not going on my own obviously with a crew and whereas i am only one who has twenty percent body missing we have a variety of different crew members.

00:54:24: extremely cold environment.

00:54:26: And I would be quite interested to see as an amputee what happens to my biometrics, you know?

00:54:32: I would track them a month before leaving Huawei out on the expedition it's about seven days and then a month after to see if there are any variations.

00:54:41: that will be obviously i guess but whether your body goes back to normal afterwards or whether it has like irreversible changes hopefully not frostbite, you kind of make me worry about that now.

00:54:54: No

00:54:54: no just give your extremities warm.

00:54:57: there is a side note.

00:55:01: I don't know if you ever hear about Wim Hof.

00:55:03: he's uh a Dutch guy who became famous for doing like a breathing technique and call exposures and i've done a lot of his stuff.

00:55:11: so i climb um a mountain just on shorts eleven degrees for three hours.

00:55:21: So, it's amazing what your body can do but you know... It is good if you are so please be safe.

00:55:27: I'm sure you're going to have people that are experts in what it is there.

00:55:31: But you might want to consider some of these breathing techniques on the side That help keep oxygenated and things like that.

00:55:40: Yeah And maybe I need to put a few hand warmers inside my socket as well.

00:55:45: You know the ones that you crack and then,

00:55:47: yeah... Yeah!

00:55:50: I think it might consider to put that in side but yeah.

00:55:53: so i've got about eighteen months to prepare for this expedition.

00:55:58: So um But the mission of this is to collect biometric data and see what can we learn from this?

00:56:07: The headline question is really, if technology can help a diverse team reach the South Pole what might that tell us about the future of healthcare back home?

00:56:16: Like hopefully there's some valuable insights we could bring to see.

00:56:21: Right

00:56:21: yes!

00:56:22: There are different ways to advance technology.

00:56:24: right one thing you're doing is taking things to the extreme.

00:56:29: I'm sort-of looking at different approaches and expanding access being in place like Ukraine, where I spend most of my time.

00:56:39: So how can we do these technologies cost efficient while maintaining the therapeutic effect?

00:56:48: And that's something that unfortunately with prosthetics you know it's... Most people with amputations in the world don't have a prosthesis and there've been several efforts to try to improve that but this is just like big challenge on bringing technologies to everybody who needs them around the world.

00:57:06: So there are different ways to push, you know?

00:57:09: The frontier of what we're using...

00:57:11: Yeah but the one thing that I've realized is that certainly for myself it's that i was surprised by how strong i am!

00:57:22: We underestimate our ability to overcome some incredibly physical and psychological challenges, like I surprised myself.

00:57:32: And i'm sure that you've seen that in your day job.

00:57:34: where are at the moment into Ukraine?

00:57:36: You must have seen quite some incredible resilience... human resilience!

00:57:41: That gives me a lot of hope to be honest..to see that ability.

00:57:46: It does not stop to impress my resilience with many people with circumstances that you will think people just give up on life, but they still push in and then have a great attitude.

00:58:04: And it's just... It is just an example of what can be achieved if put your mind into things.

00:58:15: That for sure one the most rewarding parts about working in areas like this where all these are not only It's not only the injury, but also you get attack every night and there is explosions.

00:58:30: Like last night it was pretty much a whole night.

00:58:32: And this all challenges.

00:58:39: The amputation isn't at end of path you know, unrecovering is of course more challenging under the circumstances but even then their resilience of people it's truly amazing and as well they're medics looking after them.

00:58:55: Yeah I mean that leads me nicely into to the final question of our talk and its about what gives your hope?

00:59:05: What gives you most optimism in the future?

00:59:08: Is human resilience day-to-day?

00:59:12: Well, that's an interesting question.

00:59:14: I'm not very impressed by the human race where we're capable of horrible things.

00:59:24: but at the same time there is the other side and... ...I decided to relocate to Ukraine because it was a very inspired by dedication….

00:59:39: …the level of vocation that the medics here have for their patients is something I've never seen.

00:59:45: And you know, we...I work on cutting-edge research in Sweden and Australia than I visited many developed countries where you had all of resources from around the world.

00:59:57: Something that will frustrate me sometimes are people who were very much focused about what was their job.

01:00:10: you know, this is my job and I'm not going to go beyond that because... That's not my job.

01:00:14: This' my job even though You are developing.

01:00:16: things have never been done on requires certain flexibility And I couldn't understand why there was such a resistance?

01:00:24: To just help and develop things.

01:00:27: um..and i could only conclude when you had it so good for long you sort of loose the challenge for life and improvement, and so on.

01:00:41: And when I came here doctors were working overtime with very little pay in a stressful situation limited resources still.

01:00:51: they were reaching out to people like me trying find solutions their patients the level of dedication it was really inspiring.

01:01:05: In Ukraine, in my first visit I saw more people with amputations than my whole career working with prosthetics and phantom limb pain.

01:01:12: And you know that's what i've done for a living.

01:01:17: So it really felt like My time here was much more beneficial to the people then anywhere else.

01:01:25: To answer your question at the end of this It is the resilience The good will Of some people Like, if everybody would be like that we wouldn't have these problems with the war and so on.

01:01:40: but you know... That's how we are as a race.

01:01:44: And there're good and bad things.

01:01:46: But this kind of circumstances bring best to people.

01:01:53: I just prefer to hang out for the best part in humanity.

01:02:00: That's a wonderful way to finish our conversation, Max.

01:02:03: I mean...I couldn't agree more like since becoming disabled myself in very different circumstances of course but i do tend to say the same thing as you can see either the worst Of what people have to offer or the best Like..i've been so surprised in both directions, but I tend to stick with the positive here and agree that our ability to innovate.

01:02:30: To find solutions to problems that have been created...to support people..to trust ourselves to be a lot more resilient than we think we are....I think all of that is quite motivating!

01:02:43: So at this point let's take a quick break.

01:02:45: i've got an interlude called The Taste Test.

01:02:49: I'll give you two options and tell me what your instinctive answer is.

01:02:54: So let's get started.

01:02:56: Restore or enhance?

01:02:59: Restore

01:03:00: Should technology focus on restoring human capability, or enhancing it?

01:03:06: Restor

01:03:07: The brain of the body?

01:03:10: Oh that's a tricky one!

01:03:13: Well so i'm a rationalist...I guess

01:03:19: Where will the biggest breakthroughs come from over the next decade?

01:03:24: AI.

01:03:25: I mean, AI is going to do everything that we haven't been able to do, I suppose.

01:03:29: Yeah.

01:03:30: Exoskeleton or neural interface?

01:03:36: They serve different purposes.

01:03:39: so...I suppose a neural interface.

01:03:43: Okay Which technology reaches mainstream adoption first?

01:03:48: when it comes to prosthetics

01:03:50: Yeah.

01:03:50: Probably osteo-integration.

01:03:53: Science fiction or science fact?

01:03:57: Science fact,

01:03:58: nice!

01:03:59: Perfect prosthetic...or phantom pain cure?

01:04:05: Phantom pain cure?

01:04:07: well actually let me take that back.

01:04:08: if you have a perfect prosthesis You won't have phantom limb pain so the so perfect prostheses meaning dexterous and you can feel that they care about problems.

01:04:18: Thank You Max for your time, I am absolutely grateful that you've managed to find a place where you could talk with me today!

01:04:26: I loved your insights.

01:04:27: there's so much i have learned um... And perhaps we could have conversation at some point about Osir integration.

01:04:34: see what the possibility around is?

01:04:38: That's it folks.

01:04:40: That's it for this episode of Taste Of Bionics.

01:04:43: Thank you so much for listening, I really thoroughly love this conversation and if you did so too please subscribe so you never miss an episode!

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