“Smart” prosthetic legs can help amputees achieve a naturalgait, but it's done through robotic sensors and algorithms that drive the limb forward at predetermined rates.
Seven patients who had this surgery were able to walk faster, avoid obstacles and climb stairs much more naturally than people with a traditional amputation. As a result, people with that kind of amputation struggle to control a prosthetic leg because they can't accurately sense where the leg is in space. They must rely on robotic controllers and sensors to establish a walking gait and adjust to slopes and obstacles.
A 2021 study by Herr's lab found that the muscles of a limb treated with AMI surgery produced electrical signals similar to those emitted by their intact limb. In the study, researchers compared seven AMI amputees with seven people who had traditional below-the-knee amputations. Those who'd received the AMI amputation surgery were able to walk faster, at about the same rate as people without amputations.