From the 1920s to the 1970s, shoe stores in several countries, including the United States, the UK, and Australia, featured a peculiar device known as the shoe-fitting fluoroscope. This machine, also known as an X-ray Shoe Fitter or Pedoscope, allowed customers to see an X-ray view of their feet inside shoes. Originally intended to ensure a perfect shoe fit, it became a common sight in stores catering to children whose shoe sizes changed frequently. However, growing awareness of the hazards associated with radiation exposure eventually led to the device’s demise.
The Invention of the Shoe-Fitting Fluoroscope
The exact origins of the shoe-fitting fluoroscope are somewhat disputed, with multiple claims to its invention.
- Jacob Lowe, an inventor who modified a medical device to demonstrate at shoe conventions in Boston and Milwaukee between 1920 and 1921, is often cited as one of the inventors. His US patent, filed in 1919 and granted in 1927, was later sold to the Adrian Company of Milwaukee.
- Matthew Adrian, brother of Syl Adrian, is another figure associated with the fluoroscope’s development. A 1922 advertisement credited Matthew with inventing and building one of the earliest X-ray shoe fitters.
- Clarence Karrer, the son of an X-ray equipment distributor, also claimed to have created the first unit in 1924 in Milwaukee but alleged that his idea was stolen by an employee of his father’s company.
In the UK, a company called Pedoscope filed for a British patent in 1924 and claimed to have manufactured the machines since 1920. The Pedoscope Company and the X-ray Shoe Fitter Corporation of Milwaukee emerged as the primary manufacturers of shoe-fitting fluoroscopes, distributing them worldwide.
How the Shoe-Fitting Fluoroscope Worked
The shoe-fitting fluoroscope was designed to provide an X-ray view of the feet inside a shoe, making it a unique addition to the shoe-buying experience. Here’s how it worked:
- Physical Structure: The device stood about four feet high and resembled a small column. It was constructed from metal and wood, with an opening at the base where customers placed their feet.
- Viewing Port: It featured a viewing porthole at the top, allowing customers, parents, and sales assistants to look down at an X-ray image of the feet inside the shoes.
- Internal View: The machine produced a detailed image showing the bones of the feet and the shoe’s outline, including visible stitching. The purpose was to help customers see how well the shoe fit, with specific attention to the toes’ movement and available space.
The machines were especially popular when fitting children’s shoes, as parents could observe their child’s foot position and ensure there was adequate room for growth.
Health Concerns and the Decline of the Fluoroscope
Despite its initial popularity, the shoe-fitting fluoroscope became a subject of controversy due to health concerns related to radiation exposure.
- Early Radiation Awareness: Knowledge of radiation burns existed as early as 1895 when Wilhelm Röntgen first experimented with X-rays. Short-term exposure risks were known, with symptoms like skin reddening (erythema) serving as early warnings. However, the long-term effects of chronic radiation exposure were less understood until the late 1940s when studies on atomic bomb survivors began to reveal more about the risks.
- High Radiation Levels: The fluoroscope delivered varying doses of radiation depending on the machine’s design and maintenance. American models, for example, exposed customers’ feet to an average of 13 roentgen (r) during a typical 20-second session, while some devices delivered up to 116 r in the same timeframe. British Pedoscopes, on the other hand, emitted around ten times less radiation.
- Cumulative Exposure Risks: Customers often tried multiple pairs of shoes in one visit, leading to repeated exposure. Over time, the cumulative dose could pose significant health risks, particularly for children, whose tissues are more sensitive to radiation.
- Leakage Hazards: The machines were not well-shielded, causing radiation to leak in all directions. Displaced shielding materials, often removed to improve image quality or reduce machine weight, exacerbated this problem. The leaked radiation increased the whole-body dose, putting shoe salespeople—who were frequently exposed—at higher risk.
Occupational Exposure: The Impact on Shoe Salespersons
Shoe salespersons faced chronic exposure from operating the fluoroscope. Studies conducted in the late 1940s and early 1950s revealed alarming levels of radiation at pelvis height, with measurements reaching up to 95 milliroentgen (mr) per week. This chronic exposure translated to an annual dose of about 3.7 millisieverts (mSv), potentially rising to 50 mSv, which is well above modern safety limits.
While there were no long-term follow-up studies on customers due to a lack of records, medical articles from the era raised concerns about radiation-induced injuries. Three shoe salespeople were notably affected:
- Severe Radiation Burn: In 1950, one salesperson suffered a severe burn requiring amputation.
- Dermatitis with Ulceration: Another case in 1957 involved dermatitis caused by prolonged radiation exposure.
- Basal-Cell Carcinoma: A 2004 case identified basal-cell carcinoma on the sole of a salesperson’s foot, potentially linked to chronic exposure from the device.
Regulatory Changes and the Phasing Out of Fluoroscopes
By the 1950s, scientific evaluations deemed shoe-fitting fluoroscopes ineffective for measuring fit and potentially dangerous. In 1950, a medical article emphasized that radiation-induced injuries could occur at any exposure level, suggesting that no amount of radiation was entirely safe.
This growing awareness, coupled with stricter regulations on radiation safety, led to the gradual phasing out of the machines throughout the 1960s and 1970s. By the 1980s, shoe-fitting fluoroscopes were largely obsolete, replaced by safer methods of fitting shoes.
Legacy of the Shoe-Fitting Fluoroscope
The story of the shoe-fitting fluoroscope is a cautionary tale about early technological innovation and its unintended consequences. While the device was initially embraced as a cutting-edge solution for shoe fitting, it ultimately underscored the importance of safety in product design and operation.
Today, the fluoroscope is a relic of the past, with some surviving models displayed in museums, including the Science Museum in London. They serve as historical reminders of how far we’ve come in understanding and managing the risks of radiation exposure.
Conclusion: From Innovation to Obsolescence
The rise and fall of the shoe-fitting fluoroscope reflect both the promise and peril of early 20th-century innovation. While it once stood as a symbol of modernity in shoe stores, it eventually became a lesson in safety and the limits of technology. Today, we benefit from more informed safety standards, ensuring that such devices are not only effective but also safe for users and operators alike.
