BERTOLT MEYER PULLS OFF HIS LEFT FOREARM and gives it to me Its smooth and black and the hand has a clear silicone cover like an iPhone case Beneath the rubbery skin are skeletal robotic fingers of the sort you might see in a sci-fi movie-the cool factor Meyer calls it bull I hold the arm in my hand Its pretty light I say Yes only a couple of pounds he responds bull I try not to stare at the stump where his arm should be Meyer explains how his prosthetic limb works The device is held on by suction A silicone sheath on the stump helps create a tight seal around the limb It needs to be comfortable and snug at the same time he says bull Can I touch it I ask REPLACEABLEGo ahead he says I run my hand along the sticky silicone YOU and it helps dispel my uneaseshy The same technologies dri ving the revolut ion

in personal electronics are ushering in a new the stump may look strange era in bionic limbs and organs

but the arm feels strong and by GEOFF BRUMFIEL

healthy bull Meyer 33 is slightly built and has dark features and a friendly face A native of

photograph by JAMES CHEADLE

Hamburg Germany currently --- - - -shyliving in Switzerland he was born with only an inch or so ofarm below the left elbow He has worn a prosthetic limb on and off since he was 3 months old The first one was passive just to get his young mind accustomed to having something foreign attached to his body When he was 5 years old he got a hook which he controlled with a harness across his shoulders He didnt wear it

much until he joined the Boy Scouts when he was Right Enginee r created a robor- called the Bionic 12 The downside is that it is extremely uncomfortshyMan-uelng prosthetic limbs and artificial organs able because youre always wearing the harness he worth $1 million-to showcase how much of says bull This latest iteration is a bionic hand withthe human body oan now be rebuilt with metal plutio and oircutlry each finger driven by its own motor Inside ofthe

68 SMITHSONIA NOOM I September 2013

molded forearm are two electrodes that respond to muscular signals in the residual limb Sending a signal to one electrode opens the hand and to the other closes it Activating both alshylows Meyer to rotate the wrist an unshynerving 360 degrees The metaphor that I use for this is learning how to parallel park your car he says as he opens his hand with a whir At first its a little tricky but you get the hang ofit

Touch Bionics the maker of this mechanical wonder calis it the i-limb The name represents more than marketing Improved software longer-lasting batteries and smaller more power-efficient microprocesshysors-the technologies driving the revolution in personal electronicsshyhave ushered in a new era in bionics In addition to prosthetic limbs which are more versatile and user-friendly than ever before researchers have deshyveloped functioning prototypes of ar~ tificial organs that can take the place ofones spleen pancreas or lungs And an experimental implant that wires the brain to a computer holds the promise of giving quadriplegics conshytrol over artificial limbs Such biOluc marvels will increasingly find their way into oWlives and our bodies We have never been so replaceable

I met Meyer on a summer day in London in the courtyard of a 19thshycentury cookie factoryMeyer is a soshycial psychologist at the University of Zurich but his personal experiences with prosthetics have instilled in him a fascination with bionic techshynology He says the past five years in particular have seen an explosion of innovation As we chatted over coffee engineers worked on a novel demonshystration in a nearby building During the past few months they had been gathering prosthetic limbs and artifishycial organs fro m around the world to be assembled into a single artificial ~tnlCture named the Bionic Man You can see the startling results in a docshyurnentary airing October 20 on the Smithsonian Channel

Engineers designed the Bionic Man to enable several ofits hUlllan-depenshydent Parts to operate without a body For instance although the robot is

70 SMITHSONIANOOM I Se p [ember 2013

Prosthetics

are Improving so quickly that one inventor boldly predicts that disabilities will be largely eliminated by the end of the 21st century

fitted with i-limbs it doesnt posshysess the nervous system or brain to make them work Instead the Bionic Man can be controlled remotely via a compute r and specially designed inshyterlacing hardware while a Bluetooth connection can be used to operate the i-limbs Nonetheless the robo t vividly showcases how much of our bodies can be replaced by circuits plastic and metal Adding to the drashymatic effect the Bionic Mans face is a silicone replica of Meyers

Rich Walke r the managing direcshytor of the project says his team was able to rebuild more than 50 percent of the human body The level ofprogshyress in bionics surprised not only him but even the researchers who

had worked on the artificial organs he says Although multiple artificial organs cant yet function together in a single human body the scenario has become realistic enollgh that bioethicists theologians and others are contending with the question How much of a human being can be replaced and still be considered human For many the c riterion is whether a device enhances or inshyterferes with a patients ability t o relate to other people Theres broad agreement for instance that tech shyllology that restores motor functions to a s troke victim or provides sight to the blind does not make a person less human But what about technolshyogy that could one day transform the brain into a semi-organic supercomshyputer Or endow people with senses that perceive wavelengths of light frequencies of sounds and even types of energy that are normally beyond our reach Such people might no lonshyger be described as strictly human regardless of whether such enhanceshyments represent an improvement over the original model

These big questions seem far away when I firs t see engineers working on the Bionic Man It is still a face shyless collection ofunassembled parts Yet the arms and legs laid out on a long black table clearly evoke the hushyman form

Meyer himself speaks to that qualshyity describing his i-limb as the fir st prosthetic he has used in which the aesthetics match the engineering It truly feels like part of him he says

David Gow a Scottish engineer who created the i-limbsays one ofthe most significant accomplishments in the field of prosthetics has been making amputees feel whole again and no longer embarrassed to be seen wearing an artificial limb Patients actually want to shake peoples hands with it he says

Gow 56 has long been fascinated by the challenge of deSigning prosshythetics After briefly working in the defense industry he became an engishyneer at a government research hospishytal attempting to develop electrically powered prosthetics He had one of

bull

his first breakthroughs while trying to figure out how t o design a hand small enough for children Instead of employing one central motor the standard approach he incorporated smaller motors into the thumb and fingers The innovation both reduced the size of the hand and paved the way for articulated digits

That modular design later became the basis for the i-limb Each finger is powered by a O4middotinch motor that autoshymatically shuts down when sensors inshydicate sufficient pressure is applied to whatever is being held Not only does that prevent the hand from crushing

To Hugh Herr a biophysicist and engineer who is the director of the biomechatronics group at the Masshysachusetts Institute of Technologys Media Lab prosthetics are improving so quickly that he predicts disabilities will be largely eliminated by the end of the 21st century If so it will be in no small part thanks to Herr himself He was 17 years old when he was caught in a blizzard while climbing New Hampshires Mount Washington in 1982 He was rescued after three-andshya-half days but by then frostbite had taken its toll and surgeons had to amyen putate both his legs below the knees

many tasks as well as the human body But he believes that a prosthesis capayen ble of both walking and numingthat perfonns at the level of the human leg is just one or two decades away

The oldest known prosthetics were used some 3000 years ago in Egypt where archaeologists have unearthed a carved wooden toe attached to a piece of leather that could be fitted onto a foot Functional mechanical limbs didnt come along until the 16th century when a French battlefield surgeon named Ambroise Pare inshyvented a hand with flexible fingers op-

Below from left The earliest known artlficlaJ limba were uaed in Egypt some 3000 years 8amp0 Only recently have we begun to see exponential advances In pro6theUca auch u the I-11mb hand wom by aociaJ psychologist Bertolt Meyer which can translate hie muscle signals Into multiple grips

say a foam cup it allows for a variety of grips When the fingers and thmnb are lowered together they create a power grip for carrying large objects Another grip is formed by closing the thumb on the side of the index finger allowing the user to hold a plate or (roshytating the wrist) turn a key in a lock A technician Or user can program the iyenlimbs small computer with a menu of preset grip configurations each of which is t riggered by a specific musshycle movement that requires extensive training and practice to learn The latest iteration of the i-limb released this past April goes a step farther An app loaded onto an iPhone gives users access to a menu of 24 diffe rent preshyset grips with the touch of a button

He was determined to go mountain climbing again but the rudimentary prosthetic legs he had been fitted with were only capable of slow walking So Herr designed his own legs optiyen mizing them to maintain balance on mOlll1tain ledges as narrow as a dime More than 30 years later he holds or co-holds more than a dozen patents related to prosthetic technologies inshy

cluding a computer-controlled artifishycial knee that automatically adapts to different walking speeds

Herr personaliyuses eight different kinds of specialized prosthetic legs designed for activities that include running ice climbing and swimming Its extremely difficult he says to deshysign a single prosthetic limb to do

erated by catches and springs He also built a leg with a mechanical knee that the user could lock into place while standing But such advances were the exception Throughout most of hushyman history a person who lost a limb was likely to succumb to infection and die A person born without a limb was typically shunned

In the United States it was the Civil War that flrst put prosthetics into widespread use Amputating a shatshytered arm or leg was the best way to prevent gangrene and it took a pracshyticed surgeon just minutes to adminshyister chloroform lop off the limb and sew the flap shut Around 60000 amshyputations were pelformed by both North and South with a 75 percent

SepHlmber 20 13 SMITHSONIAN COM 11

Sluv1val rate After the war when the demand for prosthetics skyrocketed the government stepped in providing veterans with money to pay for new limbs Subsequent wars led to more advances In World War I 67000 amshyputations tookplace in Germany alone and doctors there developed new anns that could enable veterans to return to manual labor and factory work Folshylowing World War II new materials such as plastics and titanium made their way into artificial limbs You can find major innovations after every period of war and conflict says Herr

The wars in Iraq and Mghanistan are no exception Since 2006 the Deshyfense Advanced Research Project s Agency h as put some $144 million into prosthetic research to help the estimated 1800 US soldiers who have suffered traumatic limb loss

Some of th at investment went t o Herrs m ost prominent invention a bionic ankle designed for people who have lost one or both legs below the knees Known as the BiOM and sold by Herrs company iWalk (there are a lot of lowercase js floating around the prosthetics industry these days) the device-fitted with se nsors mulshytiple microprocessors and a batteryshypropels users forward with each step helping amputees regain lost energy as they walle Roy Aaron a professor of orthopedic surgery at Brown Unishyversity and the director ofthe Brown VA Center for Restorative and Regenshyerative Medici~e says people who use a BiOM compare it to striding on a moving walkway at an airport

Herr e nvisions a future where prosthetics such as the BiOM can be merged with the human body Ampushytees who sometimes have to endure chafing and sores while wearing their devices might one day be able to atshytach their artificial limbs directly to their bones wi th a titanium rod

Michael McLoughlin the engineer leading development of advanced prosthetics at the J ohn s Hopkins University Applied Physics Laborashytory also wants to see bionic limbs

fel1cliprddaSmithronlwt ChatUl~ljUJU (ttl bionicsQtO I SruitluonLancombiunw

74 SMITHSONIANCOM I Septemb er 20 13

Each finger is powered by a O4-inch motor that senses when sufficient pressure IS

being applied_ AniPhone appglves users access to a menu of 24 different grips

that are more integrated with the hushyman body The Modular Prosthetic Limb (MPL) an artificial arm-andshyhand mechanism that was built by the Johns Hopkins lab has 26 joints controlled by 17 separate motors and can do just about everything a norshymal limb can do says McLoughlin But the MPLs sophisticated moveshyments are limited by the level of technology available for interfacing with the bodys nervous system (Its comparable to ow ning a top-of-theshyline personal computerthats h ooked up to a slow Internet connection) Whats needed is a way to increase the data flow-possibly by establishing a direct uplink to the brain itself

in April 2011 researchers at Brown

achieved just that w hen they conshynecte d a robotic arm directly into the mind ofCathy Hutchinson a 58-yearshyold quadriplegic who is unable to move her arms and legs The results captured on video are astounding Cathy can pick up a bottle and lift it to her mouth to drink

This feat was made possible when neurosurgeons c reated a small hole in Cathys skull and implanted a sensor the size of a baby ltlSpirin into her moshytOr cortex which controls body moveshyments On the outsid e of the sensor are 96 hair-thin electrodes that can detect electrical signals emitted by neurons When a person thinks about penormshying a specific phYSical task-such as lifting her left arm or grabbing a botshytle with her right h and - the neurons emit a distinct pattern of electrical pulses associated with that m otion In Hutchinsons case neuroscientists first asked her to imagine a series of body movements with each mental effort the electrodes implanted in her brain picked up the electrical pattern generated by the neurons and transshymitted it through a cable to an extershynal computer near her wheelchair Next the researchers translated each pattern into a command code for a roshybotic arm mounted on the computer allowing her to control the mechanshyical hand mth her mind The whole study is embodied in one frame ofthe video and that is Cathys smile when she puts the bottle down says Brown neuroscientist J ohn Donoghue who co-clirects the research program

Donoghue hopes this study will eventually make it possible for the brain to fonn a direct interlace with bionic limbs Another goal is to develop an implant that can record and transshymit data wirelessly Doing so would eliminate the cord that presently conshynects the brain to the computer allowshying mobility for the user and lowering t he risk of infection that results from mres passmgthrough the skin

Perhaps the toughest challenge faced by inventors of artificial organs is the bodys defense system If you put something in the whole bodys immune system will try to isolate it says Joan Taylor a professor ofpharshy

molded forearm are two electrodes that respond to muscular signals in the residual limb Sending a signal to one electrode opens the hand and to the other closes it Activating both alshylows Meyer to rotate the wrist an unshynerving 360 degrees The metaphor that I use for this is learning how to parallel park your car he says as he opens his hand with a whir At first its a little tricky but you get the hang ofit

Touch Bionics the maker of this mechanical wonder calis it the i-limb The name represents more than marketing Improved software longer-lasting batteries and smaller more power-efficient microprocesshysors-the technologies driving the revolution in personal electronicsshyhave ushered in a new era in bionics In addition to prosthetic limbs which are more versatile and user-friendly than ever before researchers have deshyveloped functioning prototypes of ar~ tificial organs that can take the place ofones spleen pancreas or lungs And an experimental implant that wires the brain to a computer holds the promise of giving quadriplegics conshytrol over artificial limbs Such biOluc marvels will increasingly find their way into oWlives and our bodies We have never been so replaceable

I met Meyer on a summer day in London in the courtyard of a 19thshycentury cookie factoryMeyer is a soshycial psychologist at the University of Zurich but his personal experiences with prosthetics have instilled in him a fascination with bionic techshynology He says the past five years in particular have seen an explosion of innovation As we chatted over coffee engineers worked on a novel demonshystration in a nearby building During the past few months they had been gathering prosthetic limbs and artifishycial organs fro m around the world to be assembled into a single artificial ~tnlCture named the Bionic Man You can see the startling results in a docshyurnentary airing October 20 on the Smithsonian Channel

Engineers designed the Bionic Man to enable several ofits hUlllan-depenshydent Parts to operate without a body For instance although the robot is

70 SMITHSONIANOOM I Se p [ember 2013

Prosthetics

are Improving so quickly that one inventor boldly predicts that disabilities will be largely eliminated by the end of the 21st century

fitted with i-limbs it doesnt posshysess the nervous system or brain to make them work Instead the Bionic Man can be controlled remotely via a compute r and specially designed inshyterlacing hardware while a Bluetooth connection can be used to operate the i-limbs Nonetheless the robo t vividly showcases how much of our bodies can be replaced by circuits plastic and metal Adding to the drashymatic effect the Bionic Mans face is a silicone replica of Meyers

Rich Walke r the managing direcshytor of the project says his team was able to rebuild more than 50 percent of the human body The level ofprogshyress in bionics surprised not only him but even the researchers who

had worked on the artificial organs he says Although multiple artificial organs cant yet function together in a single human body the scenario has become realistic enollgh that bioethicists theologians and others are contending with the question How much of a human being can be replaced and still be considered human For many the c riterion is whether a device enhances or inshyterferes with a patients ability t o relate to other people Theres broad agreement for instance that tech shyllology that restores motor functions to a s troke victim or provides sight to the blind does not make a person less human But what about technolshyogy that could one day transform the brain into a semi-organic supercomshyputer Or endow people with senses that perceive wavelengths of light frequencies of sounds and even types of energy that are normally beyond our reach Such people might no lonshyger be described as strictly human regardless of whether such enhanceshyments represent an improvement over the original model

These big questions seem far away when I firs t see engineers working on the Bionic Man It is still a face shyless collection ofunassembled parts Yet the arms and legs laid out on a long black table clearly evoke the hushyman form

Meyer himself speaks to that qualshyity describing his i-limb as the fir st prosthetic he has used in which the aesthetics match the engineering It truly feels like part of him he says

David Gow a Scottish engineer who created the i-limbsays one ofthe most significant accomplishments in the field of prosthetics has been making amputees feel whole again and no longer embarrassed to be seen wearing an artificial limb Patients actually want to shake peoples hands with it he says

Gow 56 has long been fascinated by the challenge of deSigning prosshythetics After briefly working in the defense industry he became an engishyneer at a government research hospishytal attempting to develop electrically powered prosthetics He had one of

bull

his first breakthroughs while trying to figure out how t o design a hand small enough for children Instead of employing one central motor the standard approach he incorporated smaller motors into the thumb and fingers The innovation both reduced the size of the hand and paved the way for articulated digits

That modular design later became the basis for the i-limb Each finger is powered by a O4middotinch motor that autoshymatically shuts down when sensors inshydicate sufficient pressure is applied to whatever is being held Not only does that prevent the hand from crushing

To Hugh Herr a biophysicist and engineer who is the director of the biomechatronics group at the Masshysachusetts Institute of Technologys Media Lab prosthetics are improving so quickly that he predicts disabilities will be largely eliminated by the end of the 21st century If so it will be in no small part thanks to Herr himself He was 17 years old when he was caught in a blizzard while climbing New Hampshires Mount Washington in 1982 He was rescued after three-andshya-half days but by then frostbite had taken its toll and surgeons had to amyen putate both his legs below the knees

many tasks as well as the human body But he believes that a prosthesis capayen ble of both walking and numingthat perfonns at the level of the human leg is just one or two decades away

The oldest known prosthetics were used some 3000 years ago in Egypt where archaeologists have unearthed a carved wooden toe attached to a piece of leather that could be fitted onto a foot Functional mechanical limbs didnt come along until the 16th century when a French battlefield surgeon named Ambroise Pare inshyvented a hand with flexible fingers op-

Below from left The earliest known artlficlaJ limba were uaed in Egypt some 3000 years 8amp0 Only recently have we begun to see exponential advances In pro6theUca auch u the I-11mb hand wom by aociaJ psychologist Bertolt Meyer which can translate hie muscle signals Into multiple grips

say a foam cup it allows for a variety of grips When the fingers and thmnb are lowered together they create a power grip for carrying large objects Another grip is formed by closing the thumb on the side of the index finger allowing the user to hold a plate or (roshytating the wrist) turn a key in a lock A technician Or user can program the iyenlimbs small computer with a menu of preset grip configurations each of which is t riggered by a specific musshycle movement that requires extensive training and practice to learn The latest iteration of the i-limb released this past April goes a step farther An app loaded onto an iPhone gives users access to a menu of 24 diffe rent preshyset grips with the touch of a button

He was determined to go mountain climbing again but the rudimentary prosthetic legs he had been fitted with were only capable of slow walking So Herr designed his own legs optiyen mizing them to maintain balance on mOlll1tain ledges as narrow as a dime More than 30 years later he holds or co-holds more than a dozen patents related to prosthetic technologies inshy

cluding a computer-controlled artifishycial knee that automatically adapts to different walking speeds

Herr personaliyuses eight different kinds of specialized prosthetic legs designed for activities that include running ice climbing and swimming Its extremely difficult he says to deshysign a single prosthetic limb to do

erated by catches and springs He also built a leg with a mechanical knee that the user could lock into place while standing But such advances were the exception Throughout most of hushyman history a person who lost a limb was likely to succumb to infection and die A person born without a limb was typically shunned

In the United States it was the Civil War that flrst put prosthetics into widespread use Amputating a shatshytered arm or leg was the best way to prevent gangrene and it took a pracshyticed surgeon just minutes to adminshyister chloroform lop off the limb and sew the flap shut Around 60000 amshyputations were pelformed by both North and South with a 75 percent

SepHlmber 20 13 SMITHSONIAN COM 11

Sluv1val rate After the war when the demand for prosthetics skyrocketed the government stepped in providing veterans with money to pay for new limbs Subsequent wars led to more advances In World War I 67000 amshyputations tookplace in Germany alone and doctors there developed new anns that could enable veterans to return to manual labor and factory work Folshylowing World War II new materials such as plastics and titanium made their way into artificial limbs You can find major innovations after every period of war and conflict says Herr

The wars in Iraq and Mghanistan are no exception Since 2006 the Deshyfense Advanced Research Project s Agency h as put some $144 million into prosthetic research to help the estimated 1800 US soldiers who have suffered traumatic limb loss

Some of th at investment went t o Herrs m ost prominent invention a bionic ankle designed for people who have lost one or both legs below the knees Known as the BiOM and sold by Herrs company iWalk (there are a lot of lowercase js floating around the prosthetics industry these days) the device-fitted with se nsors mulshytiple microprocessors and a batteryshypropels users forward with each step helping amputees regain lost energy as they walle Roy Aaron a professor of orthopedic surgery at Brown Unishyversity and the director ofthe Brown VA Center for Restorative and Regenshyerative Medici~e says people who use a BiOM compare it to striding on a moving walkway at an airport

Herr e nvisions a future where prosthetics such as the BiOM can be merged with the human body Ampushytees who sometimes have to endure chafing and sores while wearing their devices might one day be able to atshytach their artificial limbs directly to their bones wi th a titanium rod

Michael McLoughlin the engineer leading development of advanced prosthetics at the J ohn s Hopkins University Applied Physics Laborashytory also wants to see bionic limbs

fel1cliprddaSmithronlwt ChatUl~ljUJU (ttl bionicsQtO I SruitluonLancombiunw

74 SMITHSONIANCOM I Septemb er 20 13

Each finger is powered by a O4-inch motor that senses when sufficient pressure IS

being applied_ AniPhone appglves users access to a menu of 24 different grips

that are more integrated with the hushyman body The Modular Prosthetic Limb (MPL) an artificial arm-andshyhand mechanism that was built by the Johns Hopkins lab has 26 joints controlled by 17 separate motors and can do just about everything a norshymal limb can do says McLoughlin But the MPLs sophisticated moveshyments are limited by the level of technology available for interfacing with the bodys nervous system (Its comparable to ow ning a top-of-theshyline personal computerthats h ooked up to a slow Internet connection) Whats needed is a way to increase the data flow-possibly by establishing a direct uplink to the brain itself

in April 2011 researchers at Brown

achieved just that w hen they conshynecte d a robotic arm directly into the mind ofCathy Hutchinson a 58-yearshyold quadriplegic who is unable to move her arms and legs The results captured on video are astounding Cathy can pick up a bottle and lift it to her mouth to drink

This feat was made possible when neurosurgeons c reated a small hole in Cathys skull and implanted a sensor the size of a baby ltlSpirin into her moshytOr cortex which controls body moveshyments On the outsid e of the sensor are 96 hair-thin electrodes that can detect electrical signals emitted by neurons When a person thinks about penormshying a specific phYSical task-such as lifting her left arm or grabbing a botshytle with her right h and - the neurons emit a distinct pattern of electrical pulses associated with that m otion In Hutchinsons case neuroscientists first asked her to imagine a series of body movements with each mental effort the electrodes implanted in her brain picked up the electrical pattern generated by the neurons and transshymitted it through a cable to an extershynal computer near her wheelchair Next the researchers translated each pattern into a command code for a roshybotic arm mounted on the computer allowing her to control the mechanshyical hand mth her mind The whole study is embodied in one frame ofthe video and that is Cathys smile when she puts the bottle down says Brown neuroscientist J ohn Donoghue who co-clirects the research program

Donoghue hopes this study will eventually make it possible for the brain to fonn a direct interlace with bionic limbs Another goal is to develop an implant that can record and transshymit data wirelessly Doing so would eliminate the cord that presently conshynects the brain to the computer allowshying mobility for the user and lowering t he risk of infection that results from mres passmgthrough the skin

Perhaps the toughest challenge faced by inventors of artificial organs is the bodys defense system If you put something in the whole bodys immune system will try to isolate it says Joan Taylor a professor ofpharshy

bull

his first breakthroughs while trying to figure out how t o design a hand small enough for children Instead of employing one central motor the standard approach he incorporated smaller motors into the thumb and fingers The innovation both reduced the size of the hand and paved the way for articulated digits

That modular design later became the basis for the i-limb Each finger is powered by a O4middotinch motor that autoshymatically shuts down when sensors inshydicate sufficient pressure is applied to whatever is being held Not only does that prevent the hand from crushing

To Hugh Herr a biophysicist and engineer who is the director of the biomechatronics group at the Masshysachusetts Institute of Technologys Media Lab prosthetics are improving so quickly that he predicts disabilities will be largely eliminated by the end of the 21st century If so it will be in no small part thanks to Herr himself He was 17 years old when he was caught in a blizzard while climbing New Hampshires Mount Washington in 1982 He was rescued after three-andshya-half days but by then frostbite had taken its toll and surgeons had to amyen putate both his legs below the knees

many tasks as well as the human body But he believes that a prosthesis capayen ble of both walking and numingthat perfonns at the level of the human leg is just one or two decades away

The oldest known prosthetics were used some 3000 years ago in Egypt where archaeologists have unearthed a carved wooden toe attached to a piece of leather that could be fitted onto a foot Functional mechanical limbs didnt come along until the 16th century when a French battlefield surgeon named Ambroise Pare inshyvented a hand with flexible fingers op-

Below from left The earliest known artlficlaJ limba were uaed in Egypt some 3000 years 8amp0 Only recently have we begun to see exponential advances In pro6theUca auch u the I-11mb hand wom by aociaJ psychologist Bertolt Meyer which can translate hie muscle signals Into multiple grips

say a foam cup it allows for a variety of grips When the fingers and thmnb are lowered together they create a power grip for carrying large objects Another grip is formed by closing the thumb on the side of the index finger allowing the user to hold a plate or (roshytating the wrist) turn a key in a lock A technician Or user can program the iyenlimbs small computer with a menu of preset grip configurations each of which is t riggered by a specific musshycle movement that requires extensive training and practice to learn The latest iteration of the i-limb released this past April goes a step farther An app loaded onto an iPhone gives users access to a menu of 24 diffe rent preshyset grips with the touch of a button

He was determined to go mountain climbing again but the rudimentary prosthetic legs he had been fitted with were only capable of slow walking So Herr designed his own legs optiyen mizing them to maintain balance on mOlll1tain ledges as narrow as a dime More than 30 years later he holds or co-holds more than a dozen patents related to prosthetic technologies inshy

cluding a computer-controlled artifishycial knee that automatically adapts to different walking speeds

Herr personaliyuses eight different kinds of specialized prosthetic legs designed for activities that include running ice climbing and swimming Its extremely difficult he says to deshysign a single prosthetic limb to do

erated by catches and springs He also built a leg with a mechanical knee that the user could lock into place while standing But such advances were the exception Throughout most of hushyman history a person who lost a limb was likely to succumb to infection and die A person born without a limb was typically shunned

In the United States it was the Civil War that flrst put prosthetics into widespread use Amputating a shatshytered arm or leg was the best way to prevent gangrene and it took a pracshyticed surgeon just minutes to adminshyister chloroform lop off the limb and sew the flap shut Around 60000 amshyputations were pelformed by both North and South with a 75 percent

SepHlmber 20 13 SMITHSONIAN COM 11

Sluv1val rate After the war when the demand for prosthetics skyrocketed the government stepped in providing veterans with money to pay for new limbs Subsequent wars led to more advances In World War I 67000 amshyputations tookplace in Germany alone and doctors there developed new anns that could enable veterans to return to manual labor and factory work Folshylowing World War II new materials such as plastics and titanium made their way into artificial limbs You can find major innovations after every period of war and conflict says Herr

The wars in Iraq and Mghanistan are no exception Since 2006 the Deshyfense Advanced Research Project s Agency h as put some $144 million into prosthetic research to help the estimated 1800 US soldiers who have suffered traumatic limb loss

Some of th at investment went t o Herrs m ost prominent invention a bionic ankle designed for people who have lost one or both legs below the knees Known as the BiOM and sold by Herrs company iWalk (there are a lot of lowercase js floating around the prosthetics industry these days) the device-fitted with se nsors mulshytiple microprocessors and a batteryshypropels users forward with each step helping amputees regain lost energy as they walle Roy Aaron a professor of orthopedic surgery at Brown Unishyversity and the director ofthe Brown VA Center for Restorative and Regenshyerative Medici~e says people who use a BiOM compare it to striding on a moving walkway at an airport

Herr e nvisions a future where prosthetics such as the BiOM can be merged with the human body Ampushytees who sometimes have to endure chafing and sores while wearing their devices might one day be able to atshytach their artificial limbs directly to their bones wi th a titanium rod

Michael McLoughlin the engineer leading development of advanced prosthetics at the J ohn s Hopkins University Applied Physics Laborashytory also wants to see bionic limbs

fel1cliprddaSmithronlwt ChatUl~ljUJU (ttl bionicsQtO I SruitluonLancombiunw

74 SMITHSONIANCOM I Septemb er 20 13

Each finger is powered by a O4-inch motor that senses when sufficient pressure IS

being applied_ AniPhone appglves users access to a menu of 24 different grips

that are more integrated with the hushyman body The Modular Prosthetic Limb (MPL) an artificial arm-andshyhand mechanism that was built by the Johns Hopkins lab has 26 joints controlled by 17 separate motors and can do just about everything a norshymal limb can do says McLoughlin But the MPLs sophisticated moveshyments are limited by the level of technology available for interfacing with the bodys nervous system (Its comparable to ow ning a top-of-theshyline personal computerthats h ooked up to a slow Internet connection) Whats needed is a way to increase the data flow-possibly by establishing a direct uplink to the brain itself

in April 2011 researchers at Brown

achieved just that w hen they conshynecte d a robotic arm directly into the mind ofCathy Hutchinson a 58-yearshyold quadriplegic who is unable to move her arms and legs The results captured on video are astounding Cathy can pick up a bottle and lift it to her mouth to drink

This feat was made possible when neurosurgeons c reated a small hole in Cathys skull and implanted a sensor the size of a baby ltlSpirin into her moshytOr cortex which controls body moveshyments On the outsid e of the sensor are 96 hair-thin electrodes that can detect electrical signals emitted by neurons When a person thinks about penormshying a specific phYSical task-such as lifting her left arm or grabbing a botshytle with her right h and - the neurons emit a distinct pattern of electrical pulses associated with that m otion In Hutchinsons case neuroscientists first asked her to imagine a series of body movements with each mental effort the electrodes implanted in her brain picked up the electrical pattern generated by the neurons and transshymitted it through a cable to an extershynal computer near her wheelchair Next the researchers translated each pattern into a command code for a roshybotic arm mounted on the computer allowing her to control the mechanshyical hand mth her mind The whole study is embodied in one frame ofthe video and that is Cathys smile when she puts the bottle down says Brown neuroscientist J ohn Donoghue who co-clirects the research program

Donoghue hopes this study will eventually make it possible for the brain to fonn a direct interlace with bionic limbs Another goal is to develop an implant that can record and transshymit data wirelessly Doing so would eliminate the cord that presently conshynects the brain to the computer allowshying mobility for the user and lowering t he risk of infection that results from mres passmgthrough the skin

Perhaps the toughest challenge faced by inventors of artificial organs is the bodys defense system If you put something in the whole bodys immune system will try to isolate it says Joan Taylor a professor ofpharshy

Sluv1val rate After the war when the demand for prosthetics skyrocketed the government stepped in providing veterans with money to pay for new limbs Subsequent wars led to more advances In World War I 67000 amshyputations tookplace in Germany alone and doctors there developed new anns that could enable veterans to return to manual labor and factory work Folshylowing World War II new materials such as plastics and titanium made their way into artificial limbs You can find major innovations after every period of war and conflict says Herr

The wars in Iraq and Mghanistan are no exception Since 2006 the Deshyfense Advanced Research Project s Agency h as put some $144 million into prosthetic research to help the estimated 1800 US soldiers who have suffered traumatic limb loss

Some of th at investment went t o Herrs m ost prominent invention a bionic ankle designed for people who have lost one or both legs below the knees Known as the BiOM and sold by Herrs company iWalk (there are a lot of lowercase js floating around the prosthetics industry these days) the device-fitted with se nsors mulshytiple microprocessors and a batteryshypropels users forward with each step helping amputees regain lost energy as they walle Roy Aaron a professor of orthopedic surgery at Brown Unishyversity and the director ofthe Brown VA Center for Restorative and Regenshyerative Medici~e says people who use a BiOM compare it to striding on a moving walkway at an airport

Herr e nvisions a future where prosthetics such as the BiOM can be merged with the human body Ampushytees who sometimes have to endure chafing and sores while wearing their devices might one day be able to atshytach their artificial limbs directly to their bones wi th a titanium rod

Michael McLoughlin the engineer leading development of advanced prosthetics at the J ohn s Hopkins University Applied Physics Laborashytory also wants to see bionic limbs

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74 SMITHSONIANCOM I Septemb er 20 13

Each finger is powered by a O4-inch motor that senses when sufficient pressure IS

being applied_ AniPhone appglves users access to a menu of 24 different grips

that are more integrated with the hushyman body The Modular Prosthetic Limb (MPL) an artificial arm-andshyhand mechanism that was built by the Johns Hopkins lab has 26 joints controlled by 17 separate motors and can do just about everything a norshymal limb can do says McLoughlin But the MPLs sophisticated moveshyments are limited by the level of technology available for interfacing with the bodys nervous system (Its comparable to ow ning a top-of-theshyline personal computerthats h ooked up to a slow Internet connection) Whats needed is a way to increase the data flow-possibly by establishing a direct uplink to the brain itself

in April 2011 researchers at Brown

achieved just that w hen they conshynecte d a robotic arm directly into the mind ofCathy Hutchinson a 58-yearshyold quadriplegic who is unable to move her arms and legs The results captured on video are astounding Cathy can pick up a bottle and lift it to her mouth to drink

This feat was made possible when neurosurgeons c reated a small hole in Cathys skull and implanted a sensor the size of a baby ltlSpirin into her moshytOr cortex which controls body moveshyments On the outsid e of the sensor are 96 hair-thin electrodes that can detect electrical signals emitted by neurons When a person thinks about penormshying a specific phYSical task-such as lifting her left arm or grabbing a botshytle with her right h and - the neurons emit a distinct pattern of electrical pulses associated with that m otion In Hutchinsons case neuroscientists first asked her to imagine a series of body movements with each mental effort the electrodes implanted in her brain picked up the electrical pattern generated by the neurons and transshymitted it through a cable to an extershynal computer near her wheelchair Next the researchers translated each pattern into a command code for a roshybotic arm mounted on the computer allowing her to control the mechanshyical hand mth her mind The whole study is embodied in one frame ofthe video and that is Cathys smile when she puts the bottle down says Brown neuroscientist J ohn Donoghue who co-clirects the research program

Donoghue hopes this study will eventually make it possible for the brain to fonn a direct interlace with bionic limbs Another goal is to develop an implant that can record and transshymit data wirelessly Doing so would eliminate the cord that presently conshynects the brain to the computer allowshying mobility for the user and lowering t he risk of infection that results from mres passmgthrough the skin

Perhaps the toughest challenge faced by inventors of artificial organs is the bodys defense system If you put something in the whole bodys immune system will try to isolate it says Joan Taylor a professor ofpharshy

maceutics at De Montfort University in England who is developing an artishyficial pancreas Her ingenious device contains no circuitry batteries or movshying parts Instead a reservoir of insushylin is regulated by a unique gel barrier that Taylor invented When glucose levels rise the excess glucose in the bodys tissues infuse the gel causing it to soften and release insulin Then as glucose levels drop the gel re-hardens reducing the release of insulin The armiddot tificial pancreas which would be unshyplanted between the lowest rib and the hip is connected by two thin catheters to a port thatlies just beneath the skins surface Every few weeks the resershyvoir ofinsulin would be refilled using a syTinge that fits into the port

The challenge is when Taylor tested the device in pigs the animals immune system responded by formshying scar tissue known as adhesions They are like glue on internal orshygans Taylor says causing constricshytions that can be painful and lead to serious problems Still diabetes is such a widespread problem-as many as 26 million Americans are afflictedshythat Taylor is testing the artificial panshycreas in animals with an eye toward solving the rejection problem before beginning clinical trials with people

For some manufacturers of artishyficial organs the main problem is blood When it encolUlters something foreign it clots Its a particular obstashycle to crafting an effect ive artificial lung which mustpass blood through tiny synthetic tubes Taylor and other researchers are teaming up with bioshymaterial specialists and surgeons who are developing new coatings and techniques to improve the bodys acshyceptance offoreign material I think with more experience and expert help it can be done she says But beshyfore Taylor can continue her research she says she needs to find a partner to provide more funding

And private investors can be hard to come by since it may take years to achieve the technological breakshythroughs that make an invention profitable SynCardia Systems an Arizona company that makes an arshytificial heart device capableofpump-

Argument from Design

What of the watchmaker can we know from the watch That he was a careless sort for one thing losing a perfectly good timepiece in high grass or that he made it for someone equally oareless all his oookwork wasted

Dont try to wind it now Its springs like dried bird bones have lost their springiness The tiny teeth of its gears are rotted out And from the age of the watch the watohmaker too must be Similarly deteriorated

So in fact there is a great deal of correspondence between the maker and the thing he made Thats pretty surprising sinoe it seems almost never to work that way A radiant abstraot painting for example tells us nothing of the sad end of the artist or what put those dark ideas in his head

Or maybe thats all we do see when we look at those paintings or at a postcard of one tacked above the desk on a cool summer night

The oauses dont stay oauseless long and in hindsight anyway make sense we like to believe speeding on even after the watch has stopped

-David Yezzi

ing up to 25 galions ofblood per minshyute was founded in 2001 but wasnt in the black until 2011 It recently developed a portable battery-powshyered compressor weighing only 135 pounds that allows a patient to leave the confines of a hospital The FDA has approved the SynCardia Total Artific ial Heart for patients with end-stage biventricular failure who are waiting for a heart transplant

Makers ofbionic arms and legs also fight an uphill financial battle You have a high-end product with a small marke t and that does make it chalshylenging says McLoughliIL This is not like investing in a Facebook or a Google youre not going to make your billions by investing in prosthetic limbs Meanwhile government

money for advanced prosthetics could get tighte r in coming years As the wars wind down funding for this kind ofresearch is going to drop off orthoshypedic surgeon Roy Aaron predicts

Then theres the cost of purchasing a prosthetic limb or artificial organ A recent study published by the Worcesshyter Polytechnic Institute found that robotic upper limb prosthetics cost $20000 to $120000 Although some private insurance companies will cover 50 to 80 percent ofthe fee othshyers have payment caps or cover only one device in a patients lifetime Inshysurance companies are also known to question whether the most advanced prosthetics are ruedicallynecessary

Herr believes that insurance proshyviders need to radically rethink their

September 2013 I SMITHSONIANCOM 76

Above Hugh Herr who lost hleleg8 to frostbite while mountain climbing in 1982 has Invented 8everal high-tech prosthetios inoludlng the 810M artificial

ankle He personally Uges eight different prothetic leg9 specially designed for aotlvltles that include running9wlmmlng and Ice ollmblng

cost-benefit analyses Although the latest bionic prosthetics are more expensive per unit than less-complex devices he argues they reduce health care payouts across the lifetime ofthe patient When leg amputees use lowshytech prostheses they develop joint conditions knee arthritis hip arshythritis and tleyre on continual pain medication says Herr They dont walk that much because walking is difficult and that drives cardiovasshycular disease and obesity

Other trends however suggest that artificial limbs and organs may conshytinue to improve and become more afshy

fordable In the developed world people are living longer than ever and they are increasingly facing failures ofone body partoranother The nwnberonecause oflower-limbamputation in the United States is not war but diabetes which in its later stages-especially among the elderly-can hamper circulation to the extremities Moreover Donoghue believes the brain-prosthetic intershyface hes working on could be used by

78 SMITHS ONIAN COM 1 September 2013

stroke patients and people with neuroshydegenerative diseases to help restore some degree ofnormaJcy to their lives Were not there yet Donoghue adshymits adding There will come a time when a person has a stroke and if we cant repair it biologically there will be an option to get a technology that will rewire their brain

Most of those technologies are still years away but if anyone will beneshyfit it will be Patrick Kane a talkative 15-year-old with chunky glasses and wispy blond hair ShOltly after birth he was stricken by a massive infection that forced doctors to remove his left arm and part ofhis right leg below the knee Kane is one of the youngest pershysons to be fitted with an i-limb prosshythetic of the sort Meyer showed me

The thing Kane likes most is the way it makes him feel Before the looks I got were an Oh what happened to him Poor him SOlt of thing he says as we sit in a London cafe Now its Ooh Whats that Thats cool As if on cue an elderly man at the next table

chimes in 1 gotta tell you something it looks amazing Its like a Batman arm Kane does a demonstration for the man Such technology is as much about changing the way people see him as it is about changing what he can do

I ask Kane about some ofthe far-out advances that might be available to him in the coming decades Would he want a limb that was bolted to his skelshyetal system Not really I like the idea that I can take it off and be me again

he says What about a prosthetic arm that could directly interface with his brain I think that would be very inshyteresting he says But he would worry about something going wrong

Depending on what happens next Kanes future may be tilled with techshynological marvels-new hands and feet that bring him closer to or even beyond the capabilities of a so-called able-bodied person Or progress might not come so fast As I watch him dart across the road to the bus stop it occurs to me that hell be fine either way 0