Dr. Sethi and the Jaipur Foot

The New York Times has a nice obituary on Dr. Jaipur who changed the lives of countless amputees with his advanced, affordable prosthetics.
From the Times…

The Jaipur foot, which has never been patented, is available in more than 25 countries, most of them poor, many of them with great numbers of land-mine victims. Unlike many high-priced prostheses in developed countries, it can be made by traditional craftsmen, lasts more than five years and costs about $30, making it affordable for mass distribution…
Dr. Sethi came up with his invention after years of extensive research. He was helped by Ramachandra Sharma, a semiliterate craftsman who had been teaching lepers to make handicrafts and who became his assistant.
The two made a foot of vulcanized rubber but found it too heavy and stiff. So they filled the shell with sponge rubber and modified the design. They used a stiff piece for the metatarsals and added microcellular rubber for the heel, cutting wedges at its upper end to make a universal joint.
Since 1971, when Dr. Sethi presented the foot to British orthopedic surgeons at Oxford, the Jaipur foot has revolutionized lives in war-torn countries. It is very flexible, allowing the wearer to run, climb trees or pedal bicycles. It is well suited to the needs of many Asian countries in which most people sit, eat, sleep and pray on the floor. Using the Jaipur foot, a Bollywood actor and dancer, Sudha Chandra, was even able to perform a demanding dance sequence in the movie musical “Nache Mayuri.”

Technology notes from JaipurFoot.org:

1) The limbs made with this technology are closest to a normal human limb. The Jaipur Foot has virtually got the same range of movements which a normal human foot has. It has dorsi-flexion, inversion, eversion, supination, pronation and axial rotation allowing a amputee not only to walk comfortably, but also squat (sitting on hunches), kneeling, crouching, sitting cross legged, walking also on undulated terrain, running, climbing a tree and driving an automobile. In other words, it is an all-functional, all-terrain limb. The other limbs with SACH foot cannot have these flexions and functions. There are some Multi Axial Feet but these allow specific limited flexions and functions.
2) Jaipur Foot is cosmetically also closest to the human foot with toes etc. Once Jaipur Foot was developed many other companies in the world added these cosmetic feature to their limb products to look like normal Foot or Jaipur Foot.
3) Jaipur Foot is water proof as many other artificial limbs in the world are.
4) Jaipur Foot is a dual purpose foot. It may be worn with shoes or without shoes depending on the desire and the need of the patients. This feature is crucial for meeting the cultural needs of many regions of the world. For example most of the modern limbs can be used only with the shoes on with the result that such amputees cannot enter the temples, mosques etc and cannot pray or perform NAMAZ.
5) The normal life of Jaipur Foot piece is around 3 years.

Read on at NYT…
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