In the grand scheme of history our medical devices will (hopefully) seem quite primitive to people of the future. And if we make as many advances in the future as we have since the 1920s, we'll all be cybernetic demigods in no time.
We can do incredible things to extend life here in the early 21st century. Organ transplants are old hat, pacemakers are ubiquitous, we're 3D printing windpipes, and mind-control over robotic limbs is showing tremendous promise in the laboratory. Today we have an incredible amount of ways to help people live longer, healthier, more productive lives — provided you can afford it. But back in the 1920s, augmenting the human body with anything more than eyeglasses and a set of false teeth was seen as wild science fiction.