20 Years Ago, This Woman Lost a Hand. Now, Her Bionic Arm Is Defying Doctors’ Expectations

A Dutch woman's experimental prosthetic is upending clinicians' expectations of what robotic technology can offer to amputees — and it has changed her life.

Identified only as Karin, her experience is detailed in a new article published in the journal Science Robotics.

"For me, this research has meant a lot, as it has given me a better life," she said. 

Karin lost her right hand in a farming accident more than twenty years ago. In the years since, she experienced excruciating phantom limb pain that she compared to sticking her hand "in a meat grinder." But Karin also found that the prosthetic hands available to her were both uncomfortable and unreliable.

So when Karin volunteered for this study and got fitted with her experimental bionic hand, she didn’t have much to lose. Instead, she gained a functionality with the hand beyond the researchers' expectations, enabling her to do everyday tasks, like chop vegetables, pack a suitcase and eat chocolate.

The robotic hand was developed by Italian robotic limb company Prensilia and dubbed Mia. According to the researchers, the hand is capable of conducting 80% of the activities involved in everyday life.

"The acceptance of the prosthesis is critical for its successful use" said Francesco Clemente, Managing Director of Prensilia, in a statement announcing the trial’s results.

"Besides technical performance, Prensilia struggled to develop a hand that could be fully customizable aesthetically. Mia Hand was born to be shown and not hidden. We wanted the users to be proud of what they are, rather than ashamed of what was lost."

Integrating Human and Robot

For the trial, a surgical team led by Rickard Brånemar, an associate professor at Gothenburg University and CEO of Integrum, installed titanium implants into the bones in Karin’s arm, a process known as osseointegration that essentially melds the prosthetic onto the body.

Then, Karin had a specially developed implant put into her arm, connecting the prosthetic's electronics to her muscles and nervous system, enabling her to control her new robot hand with the same neural pathways she had controlled her original one.

"The biological integration of titanium implants into bone tissue creates opportunities to further advance amputee care," said Brånemar. “By combining osseointegration with reconstructive surgery, implanted electrodes, and AI, we can restore human function in an unprecedented way."

As part of the procedure, the muscles and nerves in remaining part of Karin’s arm were also moved around so they could feed more information into the prosthetic. Since the procedure, Karin's phantom limb pain has dissipated.

"Our integrated surgical and engineering approach also explains the reduction in pain, as Karin is now using somewhat the same neural resources to control the prosthesis as she did for her missing biological hand," explained Max Ortiz Catalan, head of neural prosthetics research at Australia’s Bionics Institute.

Surgeon Paolo Sassu, who conducted the first hand transplant in Scandinavia, performed the surgery on Karin. He said that Karin's operation tested new procedures that can help other patients who need prosthetics. 

"Karin was the first person with below-elbow amputation who received this new concept of a highly integrated bionic hand that can be used independently and reliably in daily life," said Catalan.

"The fact that she has been able to use her prosthesis comfortably and effectively in daily activities for years is a promising testament to the potential life-changing capabilities of this novel technology for individuals facing limb loss."