On October 22, 1985, medical engineer Van Phillips was granted U.S. Patent No. 4547913, for the “composite prosthetic foot and leg,” under the newly founded Flex-Foot, Inc.
In 1976, when Phillips was 21, his left leg was severed below the knee in a water-skiing accident. At the hospital, he was measured for a pink wood-and-rubber leg and sent home. As a young and active individual, Phillips became frustrated by the stiff and uncomfortable prosthetic options at the time.
Phillips was determined not only to create a better prosthetic for others but to also return to his athletic lifestyle. When he was a student at the Northwestern University Medical School Prosthetic-Orthotic Center, professors often discouraged him from challenging the status quo where prosthetics were designed to resemble human attributes.
Borrowing concepts from pole vaulting, the spring of a diving board and the C shape of a Chinese sword his father owned, Phillips imagined a prosthetic that would let him jump and land. Between 1976 and 1984, Phillips tested his own models until he came to the final design, which allowed him to run again and brought upon the birth of Flex-Foot, Inc.
In 1996, the Flex-Foot Cheetah or Flex-Foot Sprint III was created. The Cheetah was constructed from 100 percent carbon fiber, a material used extensively in the aerospace industry for its superior strength and flexibility.
The unique shape of the Cheetah allows the prosthetic to flex and bend to impersonate foot ligaments and musculature. Because of the C-shaped segment, the kinetic energy from the wearer’s steps distributes and provides for a vertical forward movement when the toe leaves the ground and propels the runner forward, simulating normal human gait. Every Cheetah prosthetic foot lacks a heel component and can be “tuned” for each athlete’s individual running needs.
Since the “composite prosthetic foot and leg” patent was granted, Phillip has attained approximately 100 U.S. and international patents. Phillips has made it possible for amputees to live more prosperous, active lifestyles and participate in sports such as running, skiing, hiking, and climbing.
According to an article from the New York Times, many users of the Flex-Foot Cheetah prosthetic have gone on to compete in high school and collegiate athletics, Ironman triathlons, the Paralympic Games, and even the Olympic Games. Paddy Rossbach, president and chief executive of the Amputee Coalition of America, said: “Van Phillips’s foot changed the whole field of prosthetics. It was an extraordinary change.”
In 2000, Phillips sold Flex-Foot, Inc. to Ossur, a prosthetic and orthotic company based in Iceland, which continues to sell the Cheetah and other Phillips designs.
Today, Phillip still designs for himself at his home in Mendocino, CA and is dedicated to creating prosthetic legs for land mine victims in developing countries, along with prosthetics for other various activities like snorkeling, skiing, surfing, etc.