Prosthetic Hand Delivers A Highly Functional Sense of Touch


Researchers in Italy and Switzerland are testing a remarkable new prosthetic hand that they claim will allow recipients to not only control the hands movement with their mind, but also regain a working sense of touch. Surgeons accomplished this by implanting electrodes into the remaining nerve endings in the upper arm, and then using the nervous system to transmit and receive information from the brain.

Researchers implanted the device on a volunteer amputee named Denis Sørensen, and the difference was felt immediately. "The sensory feedback was incredible. When I held an object, I could feel if it was soft or hard, round or square. I could feel things that I hadn’t been able to feel in over nine years," he said.

Researches blindfolded Sørensen and put headphones on him, then proceeded to measure his ability to perform over 700 unique tests designed to quantify both the extent of motor control he had over the new hand, and the accuracy of his new sense of touch. During that time, he was able to distinguish a between a baseball and an orange based only on the resistance he felt when he squeezed it. Even more promising, as he got familiar with the hand, he was able to use the sense of touch to help him accomplish everyday tasks that current robotic prosthetics users struggle with, like picking up a coffee cup by the handle gently enough to not break it, but tightly enough to keep from dropping it.

By systematically cataloging hundreds of touch-based tasks, researchers are establishing a legitimate functional value to developing prosthetics that can transmit sensory information back to the brain. "They really showed the value of having this feedback to the user and, in some ways, justified, in an actual use setting, an implanted interface with the nerve." – Dustin Tyler, biomedical engineer at Case Western Reserve University.

The hand is still far from ready for everyday use, and as per European law, the implant had to be removed from Sørensen after one month. Currently, there is so much computer processing required to convert what the hands sensors felt into a signal that the nervous system and brain could transmit and process, that the hand had to be connected to a laptop at all times. Researchers are hoping to miniaturize a computer that could be housed within the hand so that it was a self contained unit. An additional concern is that researchers do not know how long the electrode implants that connect the hand to the remaining nerve endings will last.

While researchers have a long road ahead before a functional and feature rich prosthetic hand is available that can take commands in the form of thought and deliver a useful sense of touch, much of the seemingly impossible has been proven possible, which leaves amputees like Sørensen hopeful that soon there will be viable alternatives to the devices that are currently available.

Enjoy HIStalk Connect? Sign up for update alerts, or follow us at @HIStalkConnect.

↑ Back to top

Founding Sponsors

Platinum Sponsors