Michael Goldfarb, professor at Vanderbilt University, has designed a prosthetic ankle that perfectly mimics the movement of a human ankle. Will new technologies, including 3D-printing, allow faster innovation in the prosthetics research ?
The key difference between Goldfarb's device and conventional prosthetics is that Goldfarb's design is robotic, which allows it to adapt to the ground it is “walking” on. ‘This device first and foremost adapts to what's around it, Goldfarb explains in a video promoting his innovation, "It's smart and intelligent.”
As explained on the University website : “Prosthetic ankles available now are static, meaning users can’t adjust their feet to different terrains.”
The new robotic ankle is very different from traditional ones, with its tiny motor and sensors working together to either conform to the walking surface or remain stationary, depending on what the user needs. Mike Sasser, who was one of the first to be implanted with the robotic ankle at the University’s mechanical engineering laboratory, explains how the robotic ankle improved his life. “[The robotic ankle] moves the foot for you, as you step it will pick it up so you don't drag it on the ground.”
“I've tried hydraulic ankles that had no sort of microprocessors, and they've been clunky, heavy and unforgiving for an active person. This isn't that,” says Sasser. “This whole idea of discomfort, of instability, they just go away with this device,” said Goldfarb.
There’s another, less obvious benefit to the robotic ankle: it allows people to wear many types of shoes that don’t play nicely with traditional prosthetics. The ankle simply adapts, Goldfarb explains on the Vanderbilt webpage. “You can walk up slopes, down slopes, up stairs and down stairs, and the device figures out what you’re doing and functions the way it should.”
Keep in mind that when it comes to prosthetics, either traditional or more innovative, robotic or bionic ankles, new wearers still have to go through a long period of rehabilitation. Indeed, patients need to be followed and regularly seen by different health professionals, who make sure that the patient's adaptation to the new prosthetic is going well.
A brighter future for amputees and patients
This innovation is expected to change many lives. Research published in 2007 by the International Society for Prosthetics and Orthotics revealed that over 35% of power-operated prosthetics and 45% of electric prosthetics are eventually abandoned by their owners, overwhelmingly because the current generation of powered-prosthetics are extremely difficult to use.
Other companies and university labs are trying to revolutionize the prosthetics field as well, like the MIT Media Lab’s Biomechatronics Group or the Open Bionics company. Indeed, recent technologies, including 3D-printing, allow them to create tailor-made prosthetics and sockets, creating higher-fidelity, cheaper limbs.
On the manufacturing front, an international NGO called Handicap International, has already begun using 3D-printing technology to make custom orthopedics. The key advantage with 3D-printing is the faster production times, which translates directly into wider outreach.
According to Future Market Insights, the orthopaedic prosthetics market is expected to be valued at more than 3 M$ by the end of 2028.