It looks like the next generation of prosthetic limbs is upon us. Later this year, a patient living in Rome will receive an advanced prosthetic hand with sensory capacities. The hand will be wired directly to the man's nervous system with electrodes, allowing him to control its movement — and to receive touch signals from the hand's skin sensors.
Imagine being able to pick up an object, but not being able to feel its texture, temperature, or shape. It's this lack of external feedback that has frustrated prosthetic researchers for years, but with this new hand, it appears they're inching closer to something that more closely approximates a human hand.
To make it work, the hand's electrodes will be clipped onto two of the arm's main nerves, the median and the ulnar nerves. It will form a cybernetic connection allowing for the fast and bidirectional flow of information between the patient's nervous system and the artificial hand.
According to its developer, Silvestro Micera of the Ecole Polytechnique Federale de Lausanne in Switzerland, it's the first prosthetic that will provide real-time sensory feedback for grasping. Micera made the announcement at the recently concluded AAAS conference in Boston. He added that increased sensory feelings will improve acceptance of artificial limbs among patients.
The new hand is an updated version of one that was produced in 2009.
The Independent explains:
An earlier, portable model of the hand was temporarily attached to Pierpaolo Petruzziello in 2009, who lost half his arm in a car accident. He was able to move the bionic hand's fingers, clench them into a fist and hold objects. He said that he could feel the sensation of needles pricked into the hand's palm.
However, this earlier version of the hand had only two sensory zones whereas the latest prototype will send sensory signals back from all the fingertips, as well as the palm and the wrists to give a near life-like feeling in the limb, Dr Micera said.
"The idea would be that it could deliver two or more sensations. You could have a pinch and receive information from three fingers, or feel movement in the hand and wrist," Dr Micera said.
"We have refined the interface [connecting the hand to the patient], so we hope to see much more detailed movement and control of the hand," he told the meeting.
The patient will wear the new hand for a month, and then be re-assessed. Micera is hoping to develop a permanent, full-working model within two years.
Source and images: Independent.