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What Causes Bunions?

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What Causes Bunions?

Apr 27, 2022

A bunion is a bony bump that can form at the joint of the big toe. While bunions are often benign, for some people, they can lead to stiffness and pain. Orthopedic surgeon Devon Nixon, MD, explains what causes a bunion and how to identify when it may be time to see an orthopedic specialist.

Interviewer: Maybe you have a bit of a bump on your foot, maybe it's painful, maybe it's just a little irritating, can't quite fit into the shoes that you used to wear. Is it a bunion, and what exactly is a bunion?

We're here with Dr. Devon Nixon, an orthopedic surgeon at the University of Utah Health, and he has an emphasis in lower extremity, foot, and ankle medicine.

Now, Dr. Nixon, what exactly is a bunion?

Dr. Nixon: Possibly one of the most common things that I see in practice. A bunion is more than just a bump that's forming on the outside of your big toe. What's actually happening is it's a complex change three-dimensionally in the alignment of the toe.

And sometimes it happens at a young age, so we see patients in their teenage to young adult years. And then sometimes it's acquired over time. So people in their fourth, fifth, and sixth decades of life begin to notice it gradually increasing. But it's not just a bump that's forming.

Interviewer: So what is it that causes a bunion?

Dr. Nixon: That's a great question and one that we don't have easy answers for. Probably the biggest component is genetic. We don't quite understand the genetics behind bunions, but they occur very commonly in families.

Historically, we used to put a lot of emphasis on people wearing tight shoes over the course of their lifetime. And that may or may not play a role. But my personal take is that it's not as big of a role as maybe we once put on it, that these are developing from factors that are somewhat patient-specific but largely outside of patients' control.

Interviewer: Since we understand that bunions have a genetic component to them, is there a particular population that is impacted more so you see it more commonly with?

Dr. Nixon: Certainly, bunions are more common in women than in men. They do occur in men, but certainly the heavy proportion is in favor of women.

And not all patients will have a strong family history, meaning that their mother or their grandmother, or other family members have had bunions, but certainly you hear that commonly.

But this is what we would describe in medicine is multifactorial. So there are many layers to this. Some of it is genetic, some of it is possibly shoe wear, but again, my take is that that's probably not as big of an emphasis as maybe it once was.

Interviewer: And for people that have, say, a bump on their foot, how do they know that it's a bunion and not, say, anything else that could be going on?

Dr. Nixon: I mean, certainly the easiest way to help make that distinction or determination is to come in and see someone with an orthopedic surgical focus on foot and ankle issues to help you better understand exactly what's happening.

Certainly, growths can form in your feet. But a bunion is really feeling like there's this strong bony contribution or strong bone prominence that's forming on the inside of the big toe, out by the joint. And at the same time, the big toe may be starting to drift towards the second and third toes.

So if those kinds of things are happening in concert, that's typically how a bunion looks and feels. There's a bump that's forming on the inside, but again, that's because the three-dimensional alignment of the toe is changing and not just growth that's happening at the bone level.

Interviewer: So what are some of the potential impacts that it can make on the foot on your day-to-day life if it's not treated?

Dr. Nixon: Certainly, bunions are a funny thing because they don't always bother all patients that have them. And so just because it may be a smaller "bunion" does not necessarily mean that it may not be symptomatic. So you don't necessarily have to wait until it's crossing over or underneath your second and third toes before you need to seek treatment.

The challenge is that we don't have a lot of in between options for treatment. So plenty of people try modifying their shoes to widen them so that they're more comfortable. They add some of these over-the-counter gel inserts that slide between the big toe and the second toe. And that certainly can make shoe wear and walking much more comfortable for people.

Unfortunately, doing those things does not change what we would describe as the natural history of a bunion, which is that it may slowly progress over time. And that's true for all forms of bunions.

Now, it doesn't mean that if it's progressing that it's going to be bothersome to you, but after those things no longer work, like modifying your shoes, adding in a toe spacer, if you continue to have pain and you're feeling like the bunion is limiting your quality of life, then that may be a reasonable time to start talking about what are the surgical options.

Now, bunions are extremely common. I see them many times in each clinic. Not all of them need surgery. But if you feel like you are at a position where modifying your shoes and adding some of these toe spacers is not the answer for you, then there are very reasonable things to think about from a surgical perspective, and many patients do really well from them.