In the newest breakthrough in prosthetic technology, researchers in Italy have unveiled a robotic hand that is magnetically controlled. There are no wires or electrical cables to be seen here – instead, the wearer directs the movements of the fingers with just their mind and the power of magnets. 

The device has been taken for a six-week test drive by 34-year-old Daniel, who lost his left hand in September 2022: “I suddenly found myself without a hand: one moment I had it and the next moment it was gone,” he recounted in a statement. Daniel was the perfect candidate to try out the robotic hand as he still has control over the muscles that moved the fingers in his left hand and has some phantom sensation remaining.

“There are 20 muscles in the forearm and many of them control the hand movements. Many people who have lost a hand keep on feeling it as if it is still in place and the residual muscles move in response to the commands from the brain,” explained team lead Professor Christian Cipriani of the BioRobotics Institute at the Scuola Superiore Sant’Anna in Pisa.

Six magnets were implanted into Daniel’s arm in April 2023, carefully oriented within the muscles so that all the magnetic fields pointed in the same direction. The Mia Hand robotic hand, developed by Prensilia, was mounted on a carbon fiber socket containing all the electrical systems, so there are no visible wires once the prosthesis is in place.

The technology the prosthesis runs on is called myokinetic control. When the muscles in the arm contract, the magnets move, and this motion is algorithmically translated into a command for the robotic hand to perform.

For the team, the results were quite astounding. Daniel was able to perform tasks with the robotic hand that require coordination and fine motor control, such as opening a jar, closing a zip, and cutting with a knife. He was also able to adapt the force applied by the fingers, allowing him to handle delicate and breakable objects.

“This system allowed me to recover lost sensations and emotions: it feels like I’m moving my own hand,” Daniel said. As endorsements go, they don’t come much better than that. Bolstered by this success, Cipriani said, “We are ready to extend these results to a broader range of amputations.”

Improving sensation in prosthetic limbs is a major goal for scientists working in the field. We’ve come a long way from the earliest attempts at limb replacements, and today’s bionic creations can achieve a level of movement and control that would once have been deemed impossible. This magnetically controlled hand is another impressive innovation. 

“To see the work of years of research realised in this study was a great emotion,” said first author Marta Gherardini. “Working together with Daniel has given us the awareness that we can do a lot to improve his life and the lives of many other people. This is the greatest motivation that drives us to continue our work and to always do better.”

The study is published in the journal Science Robotics.