London - A bionic hand which allows the recipient to feel “lifelike” sensations is to be transplanted on to a patient’s arm for the first time.
Until now, artificial limbs have been able to pick up brain signals destined for the absent hand and translate them into movements, but they could not give sensory feedback.
The new hand, which is attached directly to the nervous system via electrodes clipped on to two of the arm’s main nerves, aims to restore a sense of touch in amputees.
The electrodes will allow the recipient to control the hand using just their thoughts – and will also send signals back to the brain. Scientists hope the breakthrough will pave the way for a new generation of artificial limbs that more closely imitate real body parts by providing feeling and increased dexterity.
Studies have shown that up to half of hand amputees do not use their artificial limb because they are not comfortable with how it appears or functions.
Dr Silvestro Micera, of the Swiss-based Ecole Polytechnique Federale de Lausanne, who helped develop the limb’s interface, said: “This is real hope for amputees. It will be the first prosthetic that will provide real-time sensory feedback for grasping.
“It is clear that the more sensory feeling an amputee has, the more likely they will get full acceptance of that limb. We hope that one day it will be embedded in the arm and the user will just forget it is there.”
In 2009 an earlier, fixed model of the hand was temporarily attached to a patient’s nervous system via electrodes. He was able to wiggle the fingers of the robotic hand, make a fist and hold objects, and said he could feel needles being jabbed into the palm.
The new model, which will be fully attached to the arm, can deliver sensory feedback from all the fingertips, as well as the thumb, palm and wrist. The team plans to transplant it into an anonymous patient later this year.
Dr Micera, who was attending the American Association for the Advancement of Science’s conference in Boston, said: “The idea would be that it could deliver two or more sensations at one time.
“You could have a pinch and receive information from three fingers, or feel movement in the hand and wrist.
“We have refined the interface, so we hope to see much more detailed movement and control of the hand. It is intended to be as lifelike as possible.” - Daily Mail