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UK startup Metacarpal has unveiled what it claims is a world-first prosthetic for upper limbs, delivering fine motor control with no electronic components.
Metacarpal GEM is a body-powered prosthetic, with users applying their own movements to enact the device’s different grips. Reactive Grasp Technology automatically shapes fingers around objects in three different grip formations: pinch for fine control, power for lifting, and lateral for holding flat items like phones or books. Feedback from the fingertips is relayed instantly via 13 aluminium bronze pulleys that transmit the force to the user’s body, allowing for precision control and grip.
“Our goal was to build a solution that performs like an extension of the body, not a machine you have to operate,” said Fergal Mackie, founder of Metacarpal.
“By eliminating electronics and going back to the fundamentals of biomechanics, we’ve created a prosthetic that delivers reliability, responsiveness and total user confidence.”
The company was founded in 2020 after Mackie suffered two broken wrists in an accident, which sparked an interest in prosthetics. From the outset, his aim was to design a practical, sturdy prosthetic that was waterproof and didn’t need to be charged, meaning it was always available to help take on everyday tasks.
The first UK user of GEM is Jim Ashworth-Beaumont, a senior orthotist at the Royal National Orthopaedic Hospital (RNOH) who lost his right arm in June 2020 in a cycling accident while training for the British Triathlon Championships.
“Hands are all about adapting and reacting to each moment in daily life, to grasp and manipulate all kinds of objects, to apply force but also be gentle and compliant when it’s needed,” said Ashworth-Beaumont.
“To do all this reliably, in a durable and attractive package, is asking a lot. The GEM hand is the perfect answer.”
It’s estimated that over six million people worldwide are living with an upper-limb amputation. While recent years have seen much innovation in the area, upper-limb prostheses still have a high rate of abandonment, with excessive weight and difficulty of control often cited as drawbacks. Backed by a range of investors including Oxford Technology, Metacarpal is aiming to address these pain points.
“Metacarpal’s human-powered prosthetic hand does exactly that. It’s a genuine breakthrough, and we believe that Metacarpal GEM will become the accessible, everyday choice for upper-limb prosthesis users globally.”
