Surgical breakthrough restores normal gait to amputees

the prostheticsprosthetics Legs have evolved significantly in recent years, providing the wearer with greater mobility. However, to achieve a more natural-looking process, more complex algorithms are integrated with them. SensorsSensors And the engines, which is a system far from perfect.

In an article published in the magazine natureResearchers from Massachusetts Institute of Technology (Massachusetts Institute of Technology) and Brigham and Women's Hospital From Boston they describe a new surgical procedure developed to compensate for this defect. It's called the neuromuscular interface. RisingRising-Anti-AMI, it allows patients to have better control of their prostheses and a more natural gait, without having to resort to a specific algorithm.

The surgical procedure allows this patient to use his prosthetic limb in a more natural way to climb stairs. © MIT

Restore awareness of the position of the limb in space

the a movementa movement The limbs rely on pairs of agonist/antagonist muscles, where one muscle contracts while the other extends, and vice versa. During a below-knee amputation, these pairs are no longer connected, preventing the nervous system from knowing position and movement. SpeedSpeed Muscle contraction. Consequently, patients have great difficulty in feeling the position of the prosthesis in space.

The surgical procedure the researchers performed involves reattaching pairs of muscles in the limb, a technique that could be used duringAmputationAmputation Initial or during subsequent intervention. It is also suitable for arm amputations. This restores ProprioceptionProprioceptionThat is, the sensation that indicates to the brain where the limb is in space, giving the patient the impression that he has found his leg.

And it works. Patients who have the procedure can walk faster and at the same speed as a non-amputee, and avoid obstacles more easily. Movements are more natural, such as raising the “toes” of the prosthetic limb when climbing stairs, or pressing down on the ground with the same force as a non-amputee. A total of 60 patients have already undergone the AMI procedure, but the prosthesis used in the study is not yet commercially available.