Development of an electronic prosthetic leg that is completely controlled by the nervous system

American neuroscientists have developed an electronic prosthetic leg that the human nervous system can interact with in the same way it controls the movement of muscles and ligaments in real human limbs.

The operation of this neural interface was tested with the participation of seven volunteers who had amputated their legs, and the experiments showed that their walking speed increased by 41% compared to a conventional prosthesis, and as a result, the participants began to move at the same speed. In addition, this approach allows patients to adapt to movement on slopes, stairs and other difficult surfaces.

This discovery was made by a group of American neuroscientists led by MIT professor Hugh Guerra. The scientists have been working for several years to create electronic limbs that would completely replicate the functions of missing arms and legs.

As part of this project, neuroscientists developed a special type of neural interface that allows them to monitor the activity of the remaining muscles in the unamputated arm and leg and use it to control the operation of the electronic prosthesis. To do this, the scientists monitored how the electrical activity of the muscles in the healthy arms and legs changed during movement. The scientists used this data to create a program that reads signals from the muscles and forces the prosthesis to assume the desired shape during movement.

The neural interface similarly stimulates the remaining muscles after each step, allowing the patient to “feel” the missing limb, which at the same time does not differ in its properties from a real leg or arm. Professor Herr tested the operation of this system by performing surgeries on 14 people after leg amputation, connecting electrodes to the forelimb and gastrocnemius muscles.

Inserting these electrodes and connecting them to the control system of the electronic prosthetic limbs greatly accelerated the volunteers' adaptation to using the cybernetic limb and increased their speed of movement, allowing them to learn to "automatically" overcome various obstacles and walk quickly on rough terrain.

Scientists hope that later versions of the prosthetic limb will allow people to run, jump or even stand on one leg, restoring their full mobility.

The results of the initial tests were published in the scientific journal Nature Medicine.