- [Narrator] You're looking at a game changer
in prosthetics.
- [Dr. Catalan] The only one today
using electrodes implanted in the nerve
and to have sensation.
- [Narrator] The developer of this bionic system
is speaking to us from Ukraine,
where war has led to a crisis.
- There is more than 15,000 people with amputations
in the country.
- [Narrator] Let's walk through every step needed
to implant his bionic arm into a patient.
- Bionic basically means
that it is a combination between biology and electronics.
- [Narrator] But traditionally,
prosthetic arms are pretty low-fi.
Some are purely aesthetic,
made in silicone, but not functional.
Then there are functional mechanical ones
powered by a wire and a patient's own movements.
- You can think about a claw or a hook
that can open and close,
and it has a system of gears like breaks for your bicycle.
- [Narrator] Then you have fancy electric prosthesis,
where a patient can control the fingers independently
via electrodes placed on the surface of the skin.
But, how do you keep the arm in place?
- [Dr. Catalan] This is normally done with a socket,
something that is on your skin, putting a lot of pressure.
- [Narrator] It's uncomfortable and heavy,
so that's why the first step
in installing Dr. Ortiz's Catalan's bionic arm
is osseointegration,
or implanting a titanium structure directly to the skeleton.
- Osseointegration made a a big splash in the medical field.
The first application were dental implants.
- [Narrator] Eventually scientists
applied this to prosthetics
after discovering in the '50s
that if you attach titanium inside bone,
the bone cells can grow directly on the titanium,
making a very strong attachment to the residual limb.
- Say you have a transhumeral amputation above the elbow.
The surgeon will place
a titanium implant that looks like a screw
inside the center of the bone.
And you leave it there for a few months.
In that period,
the bone cells grow around the titanium implant,
and then you place a portion of the implant
that comes out through the skin,
and that's where you're gonna connect your prosthesis.
- [Narrator] Implanting into a residual limb
that has been amputated below the elbow
has its own challenges,
because there are two smaller bones,
the radius and the ulna,
and they move independently from each other.
- So they will move like this. They will move like this.
And they will also move in their own axis.
So we developed an artificial joint
that allows for those movements to take place
while preserving a natural orbit for the movement.
- [Narrator] Now, the next step
is to surgically implant the electrodes inside the body.
- We will place electrodes
in the muscles and the nerves around the residual limb.
Electrodes on the surface of the skin
are susceptible to electromagnetic interference.
- [Narrator] Stuff all around us like tools or computers
can create noise interference radiating to the electrodes
if they're merely sitting on the surface of the skin.
This will cause the prosthetic to become uncontrollable.
Even just moving your arm around
can throw off a conventional sensor.
- If it lifts a little bit,
it generates what's called a motion artifact.
If you move too fast, if you sweat,
the prosthesis become less controllable.
- [Narrator] With electrodes implanted
directly inside muscles on nerves,
you don't have any of those problems.
- If you have an amputation where the hand is gone,
you have many muscles here
that help you to control the fingers of the hand.
So there's a lot of sources that you can use
to drive the prosthesis.
- [Narrator] But in the case of an amputation
above the elbow,
you don't have as much to work with.
So the team has to get creative
and rejigger the body's original biological wiring.
- You have the biceps, and the biceps has two heads.
So it's not enough information
that we can extract from the muscles
to drive all the missing joints.
So a solution for that is
you can take a nerve that used to go to the hand
and then you transfer it into one head of the biceps.
So then when the patient thinks about closing the hand,
this part of the muscle will contract the short head.
- [Narrator] There are three big nerves in the arm,
the radial, the ulnar, and the median,
which allows you to control these three fingers.
Basically, a nerve is a collection of axons
which are bundled into fascicles.
- So if you think about my fingers
as the bundles of the nerve, what you can do is split them.
You take one of those bundles
to connect with that muscle that is available there.
And then for the other ones,
we can borrow a piece of muscle from the legs.
It's called a free muscle graft.
And then we transfer that to the arm
to connect to one of these fascicles.
- [Narrator] Next, you insert a metal electrode
into the muscle,
and connect that to the connector
inside the titanium implants.
- [Dr. Catalan] So it has a wire,
and that wire is covered
by materials that are biocompatible,
meaning that they're well taken by the body.
- [Narrator] The signals that come from your brain
to control your limbs
travel through nerves,
but these organic signals are relatively weak,
about 10,000 times smaller
than the strength of the signals
generated by these new electric plugs.
So in a way, the implanted electrodes
use the muscle like a loudspeaker,
amplifying the signals from the brain to the muscles,
and to the prosthesis.
- [Dr. Catalan] The implantable part has no batteries.
All the power happens in the prosthesis.
You can think about it as a USB port
into the nervous system.
- [Narrator] The next step involves
training the AI in the bionic hand's CPU
to understand what the signals from the brain mean.
- The way we control our limbs is by electric signals
coming down through the nerves to the muscles,
and these come in the form of electric impulses.
Those signals are captured
by the electronics of the prosthesis.
So they travel down to the prosthesis
where the brain of the prosthesis
understands what those signals are.
- [Narrator] But that CPU in the prosthesis
doesn't automatically know
what those patterns of activation mean.
The AI needs to be trained.
- [Dr. Catalan] What we do is we tell the patient
try to close your hand,
and then we record signals.
And then we say try to open your hand,
and we record the signals.
- [Narrator] And then,
the team labels that action for the AI,
translating neural signals from the brain into code
that is now understood by the tiny computer
in the prosthetic arm,
which then engages its robotic motors
to move in specific ways.
The next step involves training the patient using software.
- This was actually the first time
we saw the patient after the surgery.
We connected it to a virtual reality system.
- [Narrator] Those two cables coming out of the implants
are sending signals wirelessly to the computer,
where they are interpreted
and used to control a virtual limb.
This trains the muscles
and makes the signals more distinct and reliable
in preparation for when the patient gets their bionic limb.
But, this training also addresses another challenge
that arises from amputation.
- After you have an amputation, there's pain that remains
from something called phantom limb pain.
- [Narrator] Which is caused by the brain getting confused
and imagining that the missing limb
is frozen or twisting in awkward ways.
- So I developed some technologies
to treat phantom limb pain.
We couple those with virtual augmented reality
so the patient can engage the same neural resources
that were used to control the hand.
This helps them reduce their pain.
- [Narrator] This training is useful
in fine tuning the algorithms
that will drive the robotic motors.
But working in the virtual world is one thing.
Without their bionic arm attached,
patients will do relatively well because there's no load.
So, the final step involves fitting the prosthesis
and testing in the real world.
Patients come into the lab, put on their bionic arm,
and perform daily tasks like packing a suitcase
or picking up small objects.
- [Dr. Catalan] These are tasks that can tell you
a little bit about the function
the patient has with the prosthesis.
- [Narrator] The team then makes adjustments
and runs further tests that evaluate and help improve
one of the most jaw dropping features of the prosthetic,
its ability to feel objects in its grasp.
- When the prosthesis make contact with the object,
there are sensors in the fingertips,
and then the brain of the prosthesis
has also a neuro stimulator,
which delivers electrical pulses to the nerves.
- [Narrator] And because the brain
receives this data from a nerve
that used to be connected to the biological limb,
it will interpret it as coming from the bionic hand.
- If I have a biological receptor in my index finger,
that has a nerve that goes all the way up to my brain.
If I put an electrode along that nerve,
it doesn't matter where I stimulate,
the brain will create a sensation
as coming from the fingertip,
it's an automatic sensation that rises in consciousness.
- [Narrator] The bionic hand uses sensors
in its thumb and index finger
to send an electrical signal through the prosthetic
and then along the original severed nerves
straight to the brain.
But the information from the fingertips
is not as nuanced as what a biological fingertip feels.
- For us, we have hundreds of sensors
that travel in hundreds of neurons.
Today, we don't have that resolution
at the neural interface.
- [Narrator] We're still a long way off
from the type of sensation
seen in the artificial limbs in Star Wars.
This hand only provides rough sensations,
but they're still useful,
because now a patient can feel
when there's an object in their hand
and if that object is slipping away.
But what about batteries?
They have to power the CPU and the motors
that drive the prosthesis, right?
- You can have interchangeable batteries,
and whenever the prosthesis run out of battery,
they just switch it.
A battery will normally last a full day.
It's very much like our phones.
Everything is self-contained.
- [Narrator] So the days of patients
carrying heavy backpacks
full of computers or bulky batteries are gone.
These days, Dr. Ortiz Catalan
really only sees patients a couple times a year
when something breaks or if he needs to fine tune anything.
But these high-end bionic hands
can come with a price tag of over $10,000.
- [Dr. Catalan] But hopefully, like any other technology,
more it's available, the less the cost will be.
We created a human machine interface,
which means we can connect the prosthesis
or we can connect to your steering wheel of your car
and you can drive it
by thinking about movement of the wrist.
You can integrate it to whatever your imagination wants.
- [Narrator] Cool.
So, can we make humans stronger, cyborg style?
- [Dr. Catalan] There will be companies
that think about human augmentation,
making a human jump higher, run faster, carry higher loads.
You can have one prosthesis
that's much stronger than a human hand,
but you cannot have a prosthesis
that is as dexterous as a human hand.
That's something that we haven't achieved
from the robotic side.
Personally, I got involved in prosthetic devices
because I wanted to solve problems.
And I'm in the business of bionic medicine.
There's so many problems out there
that have not been solved when it comes to disabilities
that I feel that is more important that we focus on that.
[ringing music]