The Present and Future Implications of Advanced Prosthetic Limbs in Sports

In this podcast, my guests and I get into detailed discussion and debate on prosthetic limb use in modern-day, and future Paralympic and Olympic sport. We discuss the intricacies of the biomechanics of these devices, and we have ethical discussions as to what should and should not be allowed in sport. Furthermore, we expand our discussion to neurological implants, and their connection to advanced prosthetic limbs, finishing with a discussion of the implications of these devices to the future of society.

Show Notes

In my Show Notes I will be giving a brief summary of each of the topics covered in this
podcast. I will also be providing a list of sources that were used to create this podcast and the
studies that the information was found in. In addition to this, I have added a section of
corrections at the bottom of the notes, where I will list corrections to any incorrect information
that was discussed in the podcast, so that the listener can be fully informed with correct and
factually based information.
Topic summaries:
The podcast begins with a short introduction of the topics and of the guests participating in the
discussion. My guests were three of my peers, all of which are current computer science majors
at the University of Notre Dame. In order of introductions, my guests were Walter Robson, Notre
Dame Junior, Maclin Freitag, Notre Dame Sophomore, and Michael Bsales, Notre Dame

The Case of Oscar Pistorius:
A large portion of the beginning of the podcast discusses the case of Oscar Pistorius, as he is a
very relevant figure in Paralympic and Olympic competition. We discuss advantages and
disadvantages of Oscar’s prostetic limbs, and how the forces on Oscar’s prosthetics differ from
those on the legs of an able-bodied athlete.

Survey of Prosthetics in sport:
After discussing Oscar in length, we moved into a discussion of prostetic limbs in Paralympic
and Olympic competition in general. We touch on several different sports, such as swimming,
cycling, jumping, and throwing events in sport. In these discussions we lay out the advantages
and disadvantages in each of these areas that prosthetic limbs supply. We also discuss the forces
on disabled athletes that prostetic limbs cause, as compared to the forces on an able-bodied

Ethical Debate of Prosthetics in Sports:
We eventually move our discussion beyond the forces within the prostetic limbs, and into the
actual ethics of using advanced prosthetic limbs in sport. We get into a debate over whether or
not athletes should be able to use any sort of aiding device within the Olympics, and whether or
not it makes sense to have a separation of Paralympic and Olympic athletes.

Future of Prosthetics and Neurological Implants:
After getting into a discussion of ethics, we began to discuss how advanced limbs may be used
and whether or not these advanced limbs will be helpful and ethical for society. This naturally
led us to a discussion of advancing prostetic limbs and their connection to Neurological implants.
We briefly discussed the known biomechanical forces of these implants and how they effect
tissue in the brain. After this we moved on to the possibilities that devices like this can create and
how they will affect society as they continue to develop and advance.

Transcript Corrections:
At this point the assertion was made that Oscar Pistorius was the only disabled athlete to ever
compete in both Olympic and Paralympic games. This assertion is untrue. In fact, there are
several athletes who have done this. Oscar, however, is the only athlete who competed as a
running athlete, in the Paralympic and Olympic games within the same year.
At this point there was a discussion of how Oscar Pistorius lost his limbs. I stated that I thought
he had been in an accident when he was young. This is actually incorrect. Oscar was born
without calf-bones, and the decision was made to amputate his legs below the knee when he was
eleven months old.


Thomas Crooks: Hello everyone and welcome to the Crooks biomechanics podcast. Today we have a very exciting and engaging topic. We’re gonna be talking about the biomechanics of prosthetic limbs
in sports. More specifically, our question for the day is, as advanced prosthetic limbs and
neurological implants become more advanced and are integrated into the sports world. How can
athletes use biomechanics to increase performance within their sports? And what are the
implications of the future of biomechanics? And it’s advancing technology in sport? and building
off of this question, we’re going to discuss some things about neurological implants and what
these neurological implants mean for the future of prosthetic limbs, and for society in general.
And before we get into all of that, I want to introduce my guests. I’ve got three guests here today.
They’re all peers of mine that go to Notre Dame. First, we have Walter Robson, Walter Say hi.

Walter: Sup Guys, I’m Walter. I’m currently a junior computer science major here,

Thomas Crooks: Walter is going to be giving us a lot of information from the computer science aspect of
Nueralink. He’s also a sports fan, all three of my guests. They are sports fans, which is very
important for our topic. My second guest is Macklin Freitag. Macklin, would you like to
introduce yourself?

Mac: Hi I’m Mac. I’m also a compsci major and I am a sophomore

Thomas Crooks: And then my final guest is Michael Bsales. Michael, would you introduce yourself?

Michael: What’s up, I’m Michael. I’m a freshman. And I’m also a computer science major. But I’m also an
economics major, double major.

Thomas Crooks: That’ll help and also our discussion on the sports a little bit. But like I said, most importantly, they’re all big sports fans. And, and that’s a lot of what we’re going to be talking about today. Alright, so let’s get into it. I want to start by talking about less advanced prostheses, ones that
could actually be used in the Olympics. And so our big question on that line is, you know, where
your prosthetic limbs cross the line of being helpful and fair, and aiding an otherwise disabled
participant and when did they cross into the region of providing a mechanical advantage to
somebody who was, you know, previously disabled, and then has these prosthetic limbs and it
actually makes them better than a normal athlete, which is something that hasn’t quite happened
yet in sports, but prosthetic limbs are advancing so quickly, that it very much could be a problem
in the future. The place that I want to start, this discussion is with Oscar Pistorius. And Oscar
Pistorius is very relevant to this discussion because he is the only athlete to ever have competed
in both the Paralympic Games and the Olympic Games. Oscar Pistorius is a sprinter from South
Africa, and he’s a double trans tibial amputee, which means he’s amputated both legs below the knee. And Oscar Pistorius was the 2008 champion at the Paralympic 100 meter dash and 400
meter dash. And he also participated in the qualifiers for the 2008 Beijing Olympics. And he also
competed in the 2012 London Olympics. He actually made it past qualify and participated being
the only double amputee or amputee in general to compete in an Olympic Games. So we’re
gonna start with him. And we’re gonna, we’re gonna do a little discussion on the biomechanics of
Oscar Pistorius, specifically, because there’s been a lot of research done on him, considering he
was the only athlete to ever have competed at both of those levels. And so, to start, I want to lay
out a rule. This is rule 144.2 of the International Association of Athletics Federation, this is the,
you know, overseeing board of the Olympics. And the main rule that they have, when it comes to
prosthetic limbs and implants and devices that aid athletes is as follows: the use of any technical
device incorporating springs, wheels, or any other element that provide the user with an
advantage over another athlete, not using such a device, not using such a device. So basically,
anything is allowed within the scope of the Olympics, as long as it’s deemed by the board to not
give an advantage over an athlete not using that device. So an able bodied athlete would not be
allowed to use any sort of implant or, you know, aiding device but a disabled athlete is allowed
to use any sort of device that would bring them to the level equal that of another athlete right. So
if you’re disabled, you’re allowed to use prostheses. And if you’re not, you’re not

Walter: how do they How do they define normal? Because like compared to Usain Bolt, I would love to
have another six inches I could run so much faster. So like, what are they saying is normal?

Thomas Crooks: Able-Bodied

Walter: Well, yeah, able-bodied, but like, I was like looking at the video of Oscar, right? He’s a
significant. He’s like three inches taller than he would have normally been, like, his blades are
much longer than his like, Shin would be normally.

Thomas Crooks: Right?

Walter: Is that an advantage? Like he has to take less steps in the 400 meter?

Thomas Crooks: Yeah. So that’s, that’s one of the things I’m going to talk about whether gate would be an advantage or not. But they deemed that to not be like the reason? Yes. So in general, having
longer legs, and having a longer gate when running would be an advantage. But when you’re
looking at an athlete who’s disabled, you start from an area that is disabled, right from an area
that’s already behind, what they would say is fair. And so that is an advantage in general, but it’s
not an advantage for him, because it’s bringing him up to a level of equality

Walter: Yeah, but like, what is that level of equality compared to Olympian? Everyone is disabled. Those
guys are freaks of genetic nature.

Thomas Crooks: Yeah. Well, that’s that’s obviously the question that we need to debate. That’s, this is such a new area, in science and in sports, that it’s why I want to talk about it because it’s so interesting. And it’s such a hard ethical debate, like you don’t know where the line is. And that’s what we’re trying
to figure out.

Michael: I’m also wondering, do the to the blades provide, Like I know, I’ve seen things about like
Giannis Antetokounmpo, has ridiculously long Achilles tendon and it makes him way, springier.
And way, jumpier. Does, do the springs provide any more of a boost in that way?

Thomas Crooks: Yeah. So that’s something that I want to talk about right now. So there’s been several studies done on Oscar Pistorius, and the one that we’re going to be talking about on drawing from mostly
is a 2011 study in the Journal of disability and society, done by Burkett and his colleagues. There
was a lot of people that were involved in it but Burkett is the head name. And so here, here’s
some mechanical advantages that were found in this study. In the study, it was found that the
amputee had less knee joint flex in force on it throughout the sprints than able body runner. But
the opposite was true for the ankle, there was much more force on the prosthetic ankle than there
was on a normal able-bodied ankle. In addition to that, there was a study done by the IAAF,
specifically on Oscar to see if you would be allowed to compete. And in their assessment, they
noted that the striking biomechanical factors of the prosthetic limb developed an energy loss of
around 9% during the stance phase, compared to 41%, of the human ankle joint. So basically,
Oscar’s limb allow him to store energy in the ankle joint as he was running, it acts as a spring
essentially. And he was able to, that allowed his gait to be quicker, because it was, you know,
springing off the ground like aa spring, but the IAAF deemed that it didn’t give an overall
advantage, because there was so much more force that he had to generate from his knee joint
than a normal runner was because a normal runner was able to generate force from the ankle
joint, and from his feet and from the calf muscles. Whereas all of Oscar’s force, when he was
running was coming from his thighs, and from his ankle joints, or from his knee joints rather.
And so the reason that they deemed it not a mechanical advantage over other runners was not the
fact that the limb didn’t give him an advantage, it in fact, did give him an advantage in the region
of his ankles, right?

Walter: Because he didn’t have ankles.

Thomas Crooks: But the drawback is that he had to create so much more force from the knee area, that that was a disadvantage compared to other runners. So what most of the discussion we’re going to have is and what what a lot of this draws on is the fact that yes, these prosthetic limbs do provide
mechanical advantages in some ways, but they also have huge disadvantages and other ways. Like I just said, I mean, it and this was another thing that was found about Oscar Pistorius was, it
can be out of the study, this quote came it can be stated that related to lower extremity and
related to the center of gravity, the sprinting mechanics of the double amputee sprinter is entirely
different from that of the able bodied sprinters. So Oscar had to completely redevelop a way to
run in a way to center himself over his legs in order to create a similar motion and a motion that
was, you know, good enough to get him to a competitive level. So that’s where most of the
studies have shown is that there are advantages to these, there are force advantages and there’s
speed advantages to these limbs. But there’s also a lot of drawback in the fact that they can’t
move naturally. And they have to create force in a unique way. And creating force in that unique
way, in almost every single case, puts them at a metabolic disadvantage, like incredibly, because
they have to use so much more energy to create force in one spot. Versus athletes were able to
create force with multiple muscles and multiple different areas of their legs. And that’s also I’ll
touch on the few other Olympic sports later on, but most research is done in the area of running
just because it’s it’s the only area where athletes have been able to be, you know, on a
comparable level with able bodied athletes. You look like you have something to say Mac.

Mac: I guess like, when you’re looking at Olympic athletes, these are like, the greatest athletes in the
world. Yeah. And so like, I guess, how do you find what’s fair and what’s not fair? When like, if
you’re, like, for example, with like, Caster Semenya or whatever, the the South African runner,
they want her to take estrogen to make it more fair. Like, I guess, how do you create lines of
what’s fair, what’s not fair, when you’re looking at someone that has a severe disadvantage? And
then I guess, like, where, who gets to make that kind of judgment, like, isn’t providing, like the…

Walter: I think that objectively the only fair way, so for in the case of like a sprinter, right, they need to
have a sprinter that understands and is probably like a trainer or someone, perhaps, like, give
themselves the disability so that they can try out the prosthetic themself. Because like otherwise,
like I don’t know, I feel like you just have to train your legs like win Oscars case, and you can
just focus on that. One muscle that gives inherently him a training advantage because other
runners have to worry about like the whole power chain of his leg and like using the calf and like
you know, pushing off with your legs like. They have to work out more muscles,

Thomas Crooks: But able bodied, runners are at such a, like I said such a higher advantage in terms of creating force, like you’re saying, yes, this guy on the has to focus on this one motion, but this one motion is like so much more difficult and creates, you have to create so much more force in one area of
joints, then on able bodied runner, like they’re already at such a disadvantage,

Walter: But you can just focus on that.

Thomas Crooks: Well ok, you could just say a normal athlete just has to focus on his running.

Walter: No they have to focus on so much more like did the mechanics of running are so much more
complex for someone with feet than someone without feet?

Thomas Crooks: That’s actually incorrect. There’s been a lot of studies done on this and that’s why it’s so like, how?

Walter: So how does it work? How is it more complex to have no feet than it is to have feet?

Thomas Crooks: Did you, ok Walt. Okay, the the intricacies of the muscles are obviously much greater for

Walter: Is it more complex knee motion not having feet and if you do have feet?

Thomas Crooks: That’s that’s what I was saying.

Walter: Oh, okay. Yeah, okay, that makes sense.

Thomas Crooks: That’s that’s where this quote came into play was that related to the lower extremity and related to the center of gravity, the sprinting mechanics of the double amputee is entirely different than the able bodied.

Michael: The thing is like, naturally, you know how to run just they’ve been done for however many 1000s
of yours. And versus, like, he has to create a whole new way to run.

Walter: Did he lose his feet? Or was he born without feet?

Thomas Crooks: He used to he was in I believe, like an accident where he lost both? When he was young

Walter: Has he had to totally relearn how to run. Yeah, that makes a totally different because like, if
you’re using the prosthetic from birth, and your body is like, ingrained with that, I think that their
prosthetics should be under much more scrutiny because they’re they’ve had more time to adapt

Thomas Crooks: Paralympic sports has an entire committee that is devoted to assessing whether or not a prosthetic limb or like a wheelchair

Walter: They actually use, or did they just study like the physics behind it?

Thomas Crooks: Well, they study the physics behind it and the forces involved but they also Like try out
everything like they have people who are

Walter: cut their feet off or like

Thomas Crooks: No, no, no, people who already are disabled. Yeah, yeah. And so they they have an entire committee devoted to what’s fair and what’s not fair in Paralympic sport. But that really hasn’t
come into play in normal Olympic sport, just due to the fact that there hasn’t been enough
athletes who have gotten to the level of success where they’ve needed to do that,

Walter: you know, it would be cool. If there was a similar sports league where they said you can have
any advantage with the prosthetic. Like if you lost your legs make the springiest, fastest blades to
run on. I would love to see some Paralympic athletes running 10 times faster than Usain Bolt just
because they’ve got springs in their shoes, that would be crazy.

Thomas Crooks: We’ll get to that. We’ll get into that when we talk about Nueralink and, and stuff like that. But right now, I just want to touch on some other biomechanics, specific stuff about other athletes,
beyond Oscar Pistorius. Because we’ve talked a lot about running and the forces involved with
that. But I want to talk about specifically jumping, swimming, cycling and throwing.
Unfortunately, there’s not been a lot of research done on this area, just because there aren’t many
athletes who like there’s just not as many athletes who compete in these ways.

Walter: And I imagine that’s a lot more complex than running. Yeah, there’s a lot more that goes into the
power transfers of all those. like running…

Michael: In high school, I threw Javelin discus, I did a lot of different sports. It’s very, um, the power to
change compared to running, it’s much more sudden movements, and it’s much more there’s a lot
more stress on on your joints.

Walter: Yeah, there’s more stresses at play. Like you have all the torque from your torso and a lot of
those motions. It’s all about like core strength, whereas, you know, running has core strength
aspect, but mostly it’s leg mechanics.

Thomas Crooks So I’m just gonna go through these real quick. I’m gonna start with jumping in. So everything that I’m about to talk about came from an article written by Justin Keogh in the Journal of sports biomechanics in 2011. And it’s an emerging area of research and consultancy in sports
biomechanics is the title. And so, throughout this, he discussed these different areas. And when it
comes to jumping, he found that studies have been done on speed and force created in double
transtibial amputees which is the same type of amputee that Oscar Pistorius was, below the knee.
And the study found that they had very similar horizontal speed upon take off, but the full limb
able bodied athletes had a distinct advantage in vertical speed and force creation, there was much
greater knee flex for non amputee athlete, allowing them to create much higher forces and have
better performance. So when it comes to jumping, as of right now, it’s pretty clear that able
bodied athletes are at a much. You know, they had they have a much higher advantage over
anyone with prosthetic limbs, it’s very difficult to create prosthetic limbs specifically for
jumping. Yeah, it’s very hard to make

Michael: That kind of reminds me like I said before with Giannis, where there were like, when the Bucks
were scouting him in Greece, They were saying, it’s ridiculous how long his Achilles tendon is,
because so much of the vertical force comes from that ankle joint, right, and comes from being
able to push off like that.

Thomas Crooks: Yeah, and that’s one of the things that they found in this area, both for cycling and for jumping, it was found that the lack of ankle torque means that there is much, much higher hip and knee flex, and that your hip and your knee have to work a lot harder, not only during the recovery phase,
but also during the power phase of energy creation. So it’s, it’s surprising, but it’s also not that
you need, like there’s so much force created within the ankle, and the ankle is so important to
how athletes compete. So, swimming, I’m going to talk about swimming real quick. It’s very
difficult to look at kicking and how kicking affects Paralympic athletes because it’s. kick rate
underwater is almost impossible to track even with high speed cameras. But in addition to that,
there haven’t been any prosthetic limbs for athletes in Paralympic sports that directly relate to
kicking. They’ve pretty much been disallowed. Like you can’t use flippers, or anything like that,
because that’s

Mac: Can’t be like a mermaid tail type deal. That would be hype.

Thomas Crooks: That but that’s clearly an advantage.

Mac: I mean, yes. But like what if you let the normal people or normal as in… I’m sorry

Thomas Crooks: Yes. Let’s Let’s avoid the word normal. able-bodied.

Mac: If you let able bodied people have flippers that are designed to set an equal even playing field.
They’re like…

Walter: It’s jockeys. In horse racing, they all have to be the same weight.

Thomas Crooks: Yeah, but that’s that’s…

Walter: We could use prosthetics to normalize the competition if you want.

Thomas Crooks: Yeah, we’ll get to that as as we talk about Nueralink and more advanced stuff, I just want to get through the the biomechanics of what’s going on right now what is actually happening. So for swimming, studies have been done on lag and coordination of arm speed for double arm
amputees. That’s below the elbow, only though, there has not been any above elbow amputees
who have been participating at a high level [With prosthetics], but so below the elbow and lower.
And these studies have shown that like jumping amputees, the disabled athletes had very similar
motions and strategies in the pool, but they’re at a significant disadvantage in terms of force
creation and time between strokes. Just because prosthetic limbs are so much more difficult to
navigate in the water. And so when it comes to swimming, just like jumping, it’s pretty clear that
prosthetic limbs have not created any sort of advantage for athletes.

Michael: Do you think it’s possible that if they change their biomechanics in the water, swam in a different way, they would then end up being faster?

Thomas Crooks: So that’s a that’s a question. That has been heavily debated. It there’s been a lot of studies done on optimization of motion, and what is the most optimal way to move. And it seems that no matter the way a disabled athlete moves, it never can really equal the movement of a natural human
swimming in water, like we’ve optimized how you should swim, and anything outside of that
creates too much drag force when moving through the water. And so it significantly slows an
athlete down.

Michael: And now what I’m about to probably discuss a little bit later, but, um, wow, um, do you think
there are if there was a future where prosthetics are not designed in the in the same way as
human, normal limbs? And in that case, like completely designed differently to to optimize
motion in a different way?

Thomas Crooks: Yeah. Yeah, I think that’s definitely an area that we’re moving in right now. And that’s definitely something that is going to happen in the future

Walter: We should make the bionic games.

Thomas Crooks: Well. Yeah. So that’s, that’s something else that that could happen. But as it stands right now, technology like that can’t be used in Paralympic or Olympic sport due to the rule that I read at the beginning, because it gives you a distinct mechanical advantage.

Mac: There’s athletes like, what’s his name, this swimmer has like, Michael Phelps, like he has been
proven to have bigger webs in between his fingers and bigger lungs, bigger lungs, dislocating or
shoulders that can dislocate in a way that pleases swimming potential. And that’s why he’s the

Michael: I think maybe part of the idea of sports, the Olympics, and and all that is a lot is just kind of
pushing the human form and pushing the human experience as far as the as, as far as the limits
can go. And I think that in a way, that prosthetics, and adjusting the form in that way to having
different shapes on the arms having slippers at the end of your feet might almost be against the
spirit of the game in that way.

Mac: But if someone’s biologically given a mechanical advantage, how is it less fair?

Walter: Yes, they are hyper enabled.

Thomas Crooks: I see what you’re saying. But, um, as it stands right now, that’s kind of the point of Olympic Games is, you know, who are the best athletes based on just training and their own biological

Michael: pushing the human form?

Thomas Crooks: Right. And so any addition to the, you know, human form, beyond what’s naturally given to an athlete is where the line is drawn?

Mac: Why, I guess is it I guess, fair at all include any paraplegic athletes in the Olympic Games,
especially when you’re offered the Paralympics, which gives them an arbitrary distinction
between the two.

Thomas Crooks: I think that where that comes into play is, that’s a reason equality, right? If you’re denying the disabled person from competing in the games, when they’re not at a distinct mechanical
advantage, which in the case of Oscar Pistorius, it was proven that he was not. That’s where it
becomes a reason of equality in the case that just because a person is disabled should not mean
that they’re disallowed to compete in the Olympic Games,

Mac: I guess then back to the point of like a mechanical advantage of someone’s physical body? Or for
example, what’s her name? Caster Semenya, here they’re trying to use hormones to change the
physical body she has, in order to make it more quote unquote fair. Like what? How do you draw
those lines? How do you create separation between someone’s physical body and putting
restrictions on that versus someone’s physical body that you are? And then how does that I guess
relate too…

Thomas Crooks: That’s that’s the debate this entire podcast is based on. Is it not? I mean, that that’s there’s the reason that we’re having this discussion is because that line is so blurred, we don’t know. And
clearly it is a slippery slope. It’s very obvious that it could go down a path that could result in
unfairness. And that’s what we’re trying to avoid. That’s what we’re trying to draw the line there,

Mac: But isn’t in creating the paralympic games creating, removing that separation of inequality
between paraplegic athletes and normal athletes.

Thomas Crooks: I mean, that’s, that’s part of the reason why the Olympic Games in the Paralympic Games were created. Right? But when it comes to prostheses that can be used, there is a line in the
Paralympic Games like it’s not like anything goes, you know, they review everything that is
used, and it has to be within a certain boundary

Walter: Do Paralympic Games when they’re evaluating the prosthetics account? Like do they
differentiate between people born with the disability?

Thomas Crooks: no, they don’t I don’t believe so

Michael: The thing is, really your body still knows how to use the limbs like they use, like mio-electronics
can can use like the your muscle and your nervous movements in

Walter: It gets the electrical signals and operates that way yeah

Michael: Yeah so imply, your body still knows how to use it, no matter whether you were born with it or
without it. Interesting.

Thomas Crooks: Only they do differentiate. In the Paralympic Games, there’s different you know, areas of

Mac: So a double amputees not competing against single amputee?

Walter: There are tiers of disability. Of how disabled you are. So there’s like the heavily disabled? And
then less disabled participants.

Thomas Crooks: Yeah. So. So theoretically, yes, Mac, there’s there, a double amputee is not necessarily going to be competing against a single amputee. But they allow people to move within. Like they allow
people to move up and down within these categories based on like whether or not they want to.
And then obviously, deem, people with more disability to be at a different level than someone
who is like, like someone who has double amputated versus someone who is single amputated,
would start in different categories. But depending upon the performance of the double amputee,
he could be allowed to move up and into a different category based on it if he wants to, you
know what I mean?

Mac: So it’s, it’s more about performance than ability,

Thomas Crooks: Not necessarily, but you can move out of the categories, if that makes sense. All right. So I think we’ve talked a lot about the forces and the biomechanics involved in these, you know, less
advanced prosthetics. And now I want to move into the future of prosthetics, prosthetic limbs
and biological implants within the human body. So there’s a lot of research that’s been going on
in this area, there’s a lot of advancements that have been made, especially with brain implants
and their control of prosthetic limbs. To this point, the limbs that are being controlled by the
implants are not functioning at a very high level, they move very slowly. And they don’t always
work in the way that is intended. But we’re getting to a point where, once we figure out the kinks
in the process, the sky’s the limit, essentially. And so the first thing I want to talk about is a brain
implant called Nueralink. There’s a lot of different brain implants out there. For example, there’s
one at the university, or Johns Hopkins University that they’ve been working on over the past
several years. And this brain implant has allowed a quadriplegic to control robotic arms using
only his thoughts. So he’s thinking as if he was moving his arms and it moves The robotic limbs,
which is really, really cool, and it’s, it’s a crazy advancement, and it’s the first, the first human bilateral arm movement that’s ever occurred. So that’s crazy. I mean, that’s just a huge step in the
right direction. But this brain implant is only six electrodes. And they’re very large on both
hemispheres of his brain. And so it causes a lot of internal stress on his actual brain tissue. And
that’s an issue with a lot of a lot of biological brain implants, brain machine interfaces, as they
call them, so an advantage of Nueralink. So everything I’m about to say, comes out of an article
published this year by Elon Musk in the Journal of medical interest and medical internet
research. And Elon had this to say about his brain implant Nueralink versus most other implants.
And in this what he had to say, most devices for long term neural recording are arrays of
electrodes made from rigid metals are semiconductors, although rigid metal arrays facilitate
penetrating the brain, The size, Young’s modulus, bending stiffness, mismatches between stiff
probes and brain tissue, which can drive immune responses that limit the function and longevity
of these devices. So basically, normal, almost all brain implants right now that have been
developed, create biomechanical disadvantages within the brain. But Elon Musk’s system has
been created differently. And this is how he created his he says: our alternative approach is to use
thin flexible multi electrode polymer probes, the smaller size and increased flexibility of these
probes offer greater biocompatibility. So not only and also, Nueralink uses 256 electrodes versus,
you know, the scale of like six to about 28 that are used for most implants as of right now. So not
only does it give you way more control and way more, you know, ability to do things within the
human brain. But it also is biomechanically more sound than any other brain implant that’s been
created right now.

Walter: I have a question kind of about that, I think is kind of interesting. Um, you mentioned like, it’s
like better connection than ever before. And it allows you to use like more parts of your brain.
When I think about like moving my arm, I think, like, move my arm, or like, I guess, let’s say I
was shooting a basketball, right? I’m thinking about, you know, a couple of things in the
mechanics of my shot, but I’m not really able to independently control every single muscle with
like, the level of control I would like. Would Nuerallink potentially, like in future iterations of it
allow you to have some type of hyper control and like, super accurate firing of like muscles in
your fingers and hands? like to give you a level of control that just general movements, like, you
know, curling your finger would not?

Thomas Crooks: Right. And that’s, you know, kind of what we’re talking about in the future of prosthetic limbs and implants is what could happen. And yeah, I mean, I mean, there’s endless, endless
possibilities right now. Like, if we continue to advance in the way that we are, then yeah,
eventually that could be the case.

Walter: Because athletes have very high precision, right, you know, motions that they’re going to use.

Thomas Crooks: Yeah, so so where we’re at right now, brain implants are not even close to that, like, they just can’t, it’s so the functionality is

Walter: it’s more of a mouse not like you know, control individual muscles

Thomas Crooks: Right. It’s like move. I mean, you can control individual muscles, but like not on a scale that you’re describing.

Walter: Yeah, yeah, I can’t like fire my one finger muscle or whatever. You can move single fingers but
I don’t have the control to move single fingers you know on the second joint or just that first
joint? Right, you know, because I can’t do that with my normal muscles.

Thomas Crooks: Yeah, that it’s it’s not even close to that yet. And we’re Nueralink actually, hasn’t been tested on any humans. It’s only been tested on rats and primates.

Walter: Would you want to get tested on you?

Thomas Crooks: That’s a good question. No, I don’t think I would. I don’t want it to be tested on me.

Walter: Would anyone in the room let it be tested on them?

Michael: I would not.

Thomas Crooks: But also the the creation Nueralink as it stands isn’t for everybody.

Walter: I think Elon talked a little bit about that. He’s like, eventually this is like the first step towards
like a human brain computer interface.

Thomas Crooks: Right, exactly.

Michael: If I remember correctly, I think at the 2014 World Cup, the one that was in Brazil, um, they had
something similar where they, they there was someone who was paralyzed, and they kick like
they did the first kick of the of the World Cup. It was a tiny kick. He was like attached to this
big, big machine.

Mac: But yeah, that’s like

Michael: That’s the that’s what these things are designed for

Thomas Crooks: These are all leading me to a quote from Elon from the same article that pretty much sums up what we’re talking about. And this is what he says right now. He says, As it stands, although
significant technological challenges must be addressed before a high bandwidth device is
suitable for clinical application with such a device, it is plausible to imagine that a patient with
spinal cord injury could dexterously control a digital mouse and keyboard, when combined with
rapidly improving spinal stimulation techniques. In the future, this approach could conceivably
restore motor function. So conceivably, in the future, Nueralink could replace spinal cord. it can
bring back motor functioning for a disabled.

Walter: So I know I don’t know a lot about brain chemistry, but I know that like certain parts of your
brain are responsible for motion and certain part like if it’s like left brain versus the right side of
the brain, like we can pinpoint in the brain where like motor functions like come from and if
your brain, you know, hypothetically got damaged, so that like that connection, like your brain
can still fire the motors like. So would that be like a spinal cord injury where that the signals just
not getting there?

Thomas Crooks: Yeah, that’s exactly what it is.

Walter: And so, okay, because I feel like some people get like, hit on the head, though. And they like
lose the ability to move their arm. So yeah, could Nueralink help with that.

Thomas Crooks: Yes. So the way the electrodes work, is they essentially replacing damaged Nuerons.

Walter: Oh, that’s very cool.

Thomas Crooks: They’re replacing damaged neurons in your brain?

Walter: How many? How many like of those little electrodes?

Thomas Crooks: There’s 256. Yes.

Walter: There’s 256? Aren’t there like trillions of brain neurons? Do you think like future iterations will
get closer to that number? Maybe you get like a million.

Thomas Crooks: I think that the electrode approach is supposed to replace a lot at the same time, like,

Walter: Oh, so there’s some one of them, it can be like many Yes. Oh, yeah. Yeah, many neurons all
connected to the same

Thomas Crooks: And the technicalities of how it actually works is far beyond the scope of this podcast, like it will take, you can talk about it for days.

Michael: That’s a dissertation.

Thomas Crooks: Yeah, yeah. So

Walter: imagine a neural link that gave you an additional like, 8 million brain synapses?

Thomas Crooks: Well, so here’s, here’s where I want to take this podcast as we’re approaching the end is, what is what is the implications of Neuralink on the future of prosthetic limbs? And on human body
functionality? You know what can happen?

Walter: it blows the door wide open

Michael: It is kinda scary, because if you think about it, I’ve talked about this a lot with some people
where even, its not unlike the, like changing of DNA of the genes before children are born and
changing it. So your kid is taller, or changing it. So your kid might have certain traits. You’re
changing what a person is, like, it’s scary, like we don’t know. And also the financial
implications, like, how expensive is this? Who is going to have access to Nueralink, to things
that will change your brain?

Thomas Crooks: That’s a huge issue, not only with Nueralink in advanced prosthetics, but with even basic prosthetic limb use right now is the economic implications are massive, because if you are born
in a third world country, and you are born with a disability, or you are an amputee, You don’t
have access to these prosthetic limbs and these, these, you know, things that could bring you
from a level of….

Walter: Especially when you need to literally walk like a well to get water. Or, like, you know, farm in
the field. So you can eat at night.

Thomas Crooks: And so that’s, that’s also something that I think has to be taken into consideration in the future of sports is, yeah, okay. Even if a mechanical advantage is not given, what are the economic
implications of allowing people to use these because certain people have access to them? Certain
people don’t. So that’s a complicated issue.

Michael: That’s one of the beautiful things about sports is that….so many people, you can have a soccer
ball, and a goal down the street, and so many people

Walter: Not so many people can have an artificial foot.

Thomas Crooks: That’s definitely a huge factor. And then we get to the question of beyond just prosthetic limb control with Nueralink. Where do we draw the line of allowing people to have brain implants?

Walter: When do we stop being human at that point, right. When you start altering what was given to you
through genetics, and you start messing with like evolution, like speeding up that process. in
Godzilla versus King Kong, great movie, highly recommend. They use a Nueralink type device
And they’re controlling a robotic Godzilla, and it comes alive and it fries the dude controlling it.
Yeah. And then it’s just like, you know, taken over that’s, What if we have Paralympic games
where like the bionic arms just come alive, bro.

Thomas Crooks: I think that that is more in the line of science fiction, rather than science, But I see what you are saying.

Walter: Lots of science is based on science fiction. We have cell phones because of Star Wars.

Thomas Crooks: I see what you are saying, But I don’t think it would ever come to that.

Mac: But there are still huge concerns with connecting your body to the internet in any capacity.

Walter: Or to a machine. It’s all about losing control.

Mac: And with current Cyber security and with how things are set up, there is extreme risk. That is
why I would be unwilling to get anything like that installed in my body.

Thomas crooks: I agree. I agree

Walter: Maybe if you like lose motion. And you are disabled, then that cost analysis becomes very
different because you will do anything to get that back.

Thomas Crooks: See that is where I would draw the line, where society will draw the line, and I think legally where they will draw the line. You will only be allowed to get these devices if you are at a
significant disadvantage or you are disabled. Whereas, an able-bodied person is not going to be
allowed to get a modification to their body that would allow them to be over the top.

Walter: But then you really need to make the distinction between born disability and gained disability.
Because when you define the line between disabled and non-disabled persons. Like certain
people are just born with genetic superiority. Like Michael Phelps does thngs that my body could
never ever ever do. But its not just black and white. Its not just you are born with it or you are
not. When it comes to leveling that playing field, it becomes very difficult to draw the line

Michael: But also you have to be careful. I know that there is a very big movement with people with
autism. And this is more towards the issue of editing genes. But like, or people with Down
syndrome will say, I do not have a disability I am just different. Especially nowadays you do not
want to start defining people as things and start pushing towards, oh you have to get this
nueralink if you are disabled. Or you should get it or whatnot.

Thomas Crooks: We are definitely going to make it a choice. I mean we are not going to be forcing anybody to get anything

Mac: Ok, But say a kid is born and they are missing their legs from the knee down. What are the ethics
of their parents saying let’s install a Nueralink into our kids brain as a newborn. SO that he’ll
have a quote unquote, Normal childhood. Like how do you deal with that.

Walter: We Just dipped our toe in this massive public discourse that needs to start, and it needs to start
now because the technology is arriving rapidly

Michael: Right you can’t not have an answer once it is here

Walter: Yeah, because if you don’t have an answer before its here, you just have to go off of precedent.
Whoever gets the first hand on it is going to set the precedent, and everyone is just going to
normalize that

Thomas Crooks: I think that this is a topic that could have its completely own podcast devoted to it. And that’s why it is just something that I wanted to touch on briefly, as we are wrapping up here. We have
been recording for 43 minutes so I think we are going to cut it off at 45

Walter: This was great, thank you for having us Crooks.

Thomas Crooks: I really appreciate you guys being here. I am happy we had this discussion; I think it was very fruitful. There was a lot of discussion not only on biomechanical aspects but also ethical aspects
and economic aspects. I think those are probably the three main aspects that need to be
discussed. And obviously in the future as brain implants become more and more advanced there
is going to have to be more and more discussion. About where the line needs to be drawn and
about what can and cannot be given to people in terms of sporting events. But right now I think it
is safe to say that there has to be a cost benefit analysis for every person, individually, when we
are saying can this person compete in the Olympic games. Does it give them a distinct
mechanical advantage, and does that distinct mechanical advantage actually give them an
advantage or were they at such a disadvantage before that it brings them to a level of equality.
That is a question that can be debated for hours, obviously. But thank you guys for joining me,
thank you everyone for listening. We will probably touch on this topic in my future podcasts,
because it is one that I love and one that I’m very interested in.

Walter: Future Podcasts?

Thomas Crooks: Yes I do many podcasts.

Walter: Wow I am excited man

Thomas Crooks: Thank you guys so much. Thank you for listening. And we will catch you next time on the Crooks Biomechanics Podcast. Peace.


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Featured image “London Marathon – Richard Whitehead MBE” by Winniepix is licensed under CC BY 2.0.