Plastic Foams in Prosthetics

In prosthetics, as in many other fields, plastic materials were quickly adopted as soon as their usefulness was recognized, not just as a substitute for other materials, but also as a supplement in places where no other material would function as well. The plastics industry is comparatively young; not much headway was made until the start of World War II. Since then giant strides were made with the discovery of new polymers in chemical laboratories a n d the improvement of fabrication processes. Everybody knows of the revolution the plastic fibers have produced in the textile in­ dustry. At first they were a poor substitute for natural fibers, but now they are in many cases superior in a number of physical properties. Plastic foam has built a niche of its own in its short rise to prominence. Its many uses in industry would require pages to enumerate. In prosthetics the use of foam got a start about four years ago, when it was first utilized as a convenient substitute for wood. With the continued improvement of the material and perfection of better manufacturing techniques, foam is sure to find ever wider application in the artificial limb program. It might be well now to pause for some technical explanations, lest some readers get confused by the term "plastic foam." Foam brings to mind to many people the soft, spongy material such as is used in upholstery and mattresses. That it is, but this is only one kind of foam. As manufac­ tured today, foam comes in many different varieties and densities, running the entire gamut from very soft and flexible to quite rigid.