Ally A. '22 Interviews Founder of OESH Shoes Dr. Casey Kerrigan

This article originally appeared in the Women's History Month edition of The Belfield Banter.

By Ally A. '22

After noticing the plethora of health issues caused by the poor design of women’s shoes, Dr. Casey Kerrigan created her own shoe company, OESH. OESH is the only shoe company that is primarily based on medical research, as well as the only shoe company to be recognized by the National Science Foundation as entirely sustainably manufactured. Dr. Kerrigan attended the University of Chicago for her undergraduate degree and Harvard Medical School for her M.D., later completing her residency in physical medicine and rehabilitation, and earning a graduate degree in kinesiology at UCLA. Throughout her studies, Dr. Kerrigan focused on gait, and the effects shoes have on the body, thus leading her to conduct years of research at a 3D human movement laboratory. Finally, she became the first female chair of the department of physical medicine and rehabilitation at UVA. 

What is OESH and how is it different from regular shoe companies? 

OESH is the word shoe inside out. It is a company based on the research of the effects of footwear, especially in women. Women’s shoes have been designed terribly for many years, not just because they are uncomfortable, but also because they create significant health issues. For example, knee arthritis. When I began studying this, my research showed me that shoes affect your whole body and overall health, so I thought, “This is significant. If I can just make better shoes that will help women dealing with these problems and also try to prevent these problems, that would be ideal.” Although I presented many companies with the research, they would not change their design because that would basically change the whole industry. I decided it would be more effective to open a factory and start making them myself. OESH shoes also look different: they do not have any kind of heel elevation, they have a wide toe box, wide forefoot, narrow heel, and bouncy sole.

What inspired you to study human movement, gait, and the effects of footwear?

I was always fascinated with gait because I was involved in running at the high school and college levels, and I enjoyed the mechanics of it. Later, in medical school, it occured to me that we understand so much about how the heart and internal organs work, but we know so little about the gait. It seemed crazy to me that we know so much about these essential organs, but so little concerning the basic physiology of walking and running. I was excited to explore an area that hadn’t been explored before. That’s also why I went into physical medicine and rehabilitation; that specialty really appreciates gait.

What elements of the soles of other shoes, specifically sneakers, cause health issues? 

A lot of it is a result of contours in the sole, as so many shoes have a lot of contouring and foam cushioning. Our research showed that anything that deviates from a perfectly flat surface increases the loads on your joints, where we develop arthritis. Additionally, the foam that is used is called ethylene vinyl acetate, which is a material that is great for absorbing impact, but is not good at giving that energy back, causing it to collapse quickly. That’s why people say you should only wear running shoes for so many miles because their soles collapse and create further contouring and deviation from flat. There’s all of this side-to-side movement that occurs, and not just movement, but the transferring of forces from side-to-side when you walk or run, so whenever you deviate from the flat plane, that will increase the impact on your joints. 

When you started OESH, what was your mission or goal for the company? Has it evolved over time?

I started with what I thought was a very simple goal: I wanted to change the way shoes are made. But, after seeing how awful and unsustainable manufacturing is for the environment and the workers, my goal changed. Now I want to make shoes sustainably. Fortunately, all of the aspects of shoes that improve health are also sustainable. For example, while the ethylene vinyl acetate I mentioned earlier is horrible for your body, it’s actually also horrible for the environment. The material we decided to use in our 3D printers is 100% recyclable. Our other materials can decompose, too, and we work to minimize our carbon footprint in every step of the shoe making process. So many companies have soles that must be glued and abraded with three sets of chemicals, heated, and put together in long assembly lines, and it’s so much waste. When you go by a shoe factory, all you see are smoke stacks. Our design just has a flat sole and an upper portion that needs to be attached, which really simplifies the process.

What technology or equipment is involved in making OESH shoes?

Initially, when we started out, we used carbon fiber springs in the soles, so we had a machine to make the springs and a water jet saw to cut them, as well as machinery to create the shoe molds. However, we later found a more elastic material that does not compress and that lasts for an extremely long time. We realized we could use that material to make the whole shoe by 3D printing it, and that eliminated the need for the springs and water jet saw. We developed the 3D printers on our own and created the entire printing process.

To learn more about OESH or purchase a pair of shoes, visit


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