Scientists from Imperial College London have developed a unique system that interprets the signals from the nerve endings of the spinal cord and turns them into movements of the prosthetic hand. To lead hand in motion, a person only need to think about the desired action, and then the electrical impulses will be read with the motor nerves and actuate the mechanical part of the prosthesis.
The problem with the previous generation prostheses was the fact that their sensors were attached to the remaining muscles at the site of an amputated limb of the patient. Twitching of these muscles resulted in the prosthesis in motion. But often happened so that the muscles have been damaged too much, from-for what movement of the denture was highly limited. About 50% of patients simply refused prosthesis due to incorrect detection. That is why many experts have long been trying to shift its focus from the muscular to the nervous system.
British researchers went another way. They identified motor nerves which previously ran from the spinal cord to the amputated limb, and tied them with intact pectoral muscles. Then on top of the skin over these muscles was assigned to special sensors that reads muscle activity. This allowed the experimental group of amputees to give prosthetic in motion, just thinking about a particular action. Most of the subjects did not have problems with the rotation of the wrist, flexion and extension of the hand, moving it in space and so on.
To give the prosthesis the order, you need to visualize the movement of the phantom arm. The accuracy of reading such mental commands allows, for example, zipping together two separate finger that is a huge step forward compared to the previous generation of prostheses. So far, the researchers have to resort to surgery to redirect nerves inside shoulder of the patient, but they believe that in the future they will create a prosthesis that does not require invasive surgeries. Current prosthetic model should go on sale within the next three years.
