The shoe-fitting fluoroscope: a little known application of the X-ray
Since its discovery in 1895, the X-ray has provided multiple uses in the fields of medicine, dentistry, security and even shopping.
Many of the greatest scientific discoveries are eventually changed and adapted for more practical and widespread use. Since its discovery by Wilhelm Roentgen in 1895, the use of the X-ray has become commonplace.
Through the fields of medicine, dentistry, security and more, people are exposed to the use of X-rays on almost a daily basis. However, one place people of recent generations are not used to seeing the X-ray is in a shoe store.
One of the most interesting, and least known, applications of the X-ray was its use as a shoe-fitting aid in shoe stores. Anyone born in the past few decades may never have heard of the shoe-fitting fluoroscope. In fact, anyone who has undergone an X-ray and worn a large lead bib may find it hard to believe that children were regularly exposed to harmful radiation. However, in the years following World War II, the shoe-fitting fluoroscope was marketed as “revolutionary” and was available in shoe stores throughout the United States and Europe.
A new application
There are multiple claims to the invention of the fluoroscope. Its use began almost simultaneously in Great Britain and in separate cities in the United States.
In Milwaukee, Clarence Karrer, who worked for his father’s X-ray equipment business, is claimed to have invented the shoe-fitting fluoroscope in 1924 as an aid to an orthopedic shoe manufacturer. Around this same time in Boston, Jacob Lowe is said to have invented the machine to help diagnose veterans with foot problems. A patent was granted to Lowe for the technology in 1927.
No matter who invented it, the machine was marketed as a great new technology that allowed the store clerk and the parent to see the fit of a shoe on the ever-growing foot of a child.
The shoe-fitting fluoroscope, as it was known, was one of the most successful marketing ventures in the shoe industry. The machines, which were large wooden cabinets with two or three viewing “scopes,” sold for approximately $2,000. The investment was deemed well worth it. Manufacturing companies such as Adrian X-ray Shoe Fitter Inc. began producing the machines. Eventually, more than 10,000 shoe-fitting fluoroscopes could be found in shoe stores across the country.
The shoe-fitting fluoroscope was marketed as a great new technology that allowed the store clerk and the parent to see the fit of a shoe on the ever-growing foot of a child.
Source: Oak Ridge Associated Universities
Downfall of an invention
In the years after the atomic bombs were dropped in Japan, researchers learned more and more about the harmful effects of radiation exposure. Concerns about the shoe-fitting fluoroscope and radiation exposure were expressed by state health departments and in medical journals as early as 1949; however, a nation-wide ban on this machine never occurred.
Although store clerks were frequently exposed to the radiation from the machines, the radiation was more dangerous to children who placed their feet directly into the radiation. The exposure rate is thought to have been approximately 0.005 Gy to 0.058 Gy per second. If children tried on several pairs of shoes per visit it was posited that they could be exposed to as much as 0.1 Gy to 1.16 Gy. In fact, experiments indicated that radiation could exceed 1 microGy per hour as far as 10 feet away from the machine.
Even in 1950, researchers reported the maximum tolerated dose of radiation exposure was only 0.003 Gy per week. Slowly, case reports involving skin burns and stunting of bone and cartilage began to emerge.
Many people questioned if the fluoroscope added any measurable value to shoe fitting. In an editorial published in 1952 in Pediatrics, one physician wrote, “Shoe salesman interviewed in one study considered the machine a sales promotion device rather than a fitting aid.”
Throughout the late 1950s and 1960s more states instituted regulations on the devices and the amount of radiation exposure deemed safe for children. By 1970, 33 states had banned the shoe-fitting fluoroscope, and the remaining states placed extreme regulations on its use. Some states even required that a licensed physician operate it.
A relic of the past, the shoe-fitting fluoroscope was eventually banned for causing harm to the foot, something it was designed to prevent. – by Leah Lawrence
For more information:
- Lapp DR. The x-ray shoe fitter — an early application of Roentgen’s ‘new kind of ray.’ The Physics Teacher. 2004;42:354-358.
- Lewis L, Caplan PE. The shoe-fitting fluoroscope as a radiation hazard. California Medicine. 1950;72:26-30.
- Nedd CA. When the solution is the problem: a brief history of the shoe fluoroscope. AJR. 1992;158:1270.
- Kopp H. Radiation damage caused by shoe-fitting fluoroscope. BMJ. 1957;Dec.;1344-1345.
- Wheatley GM. Shoe-fitting fluoroscopes. Pediatrics. 1952;11:189-190.