Let's talk aboutBunions

What is a bunion?

A bunion is a bony bump on the joint at the base of the big toe. For some people bunions aren’t bothersome, but for others bunions may cause pain on the surface of the bunion or within connected parts of the foot.

Diagram showing a typical foot compared to a foot with a bunion that has a bulging bone near the big toe.

What causes bunions?

Bunions are often formed when the big toe becomes angled toward the other toes. This causes the joint at the base of the big toe to stick out, creating the characteristic bump. Bunions can form when bones and tendons within the foot move incorrectly when supporting weight and eventually become misaligned. It isn’t known exactly why some people develop bunions and others don’t, but it’s likely influenced by multiple factors. Studies suggest that restrictive footwear and genetics may be partially to blame.

Icons labeled “Physical therapy” and a foot in a supportive shoe labeled “Accommodating footwear”.

Do your genetics impact the likelihood of getting bunions?

Genetics may play a role in the development of bunions. Wondering if you may be genetically predisposed to this foot issue? 23andMe’s DNA kits can reveal insights about your likelihood. Grab a kit to find out what your genes may say about your feet in the 23andMe Bunions Trait report.

Health + Ancestry Service Kit

Health + Ancestry Service

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Ferrari J. (2009). “Bunions.” BMJ Clin Evid. 2009:1112

Furlotte NA et al. (2015). “23andMe White Paper 23-12: Estimating complex phenotype prevalence using predictive models.” 23andMe White Paper 23-12.

Mayo Clinic. “Bunions.” Retrieved April 22, 2019, from https://www.mayoclinic.org/diseases-conditions/bunions/symptoms-causes/syc-20354799.

Mortka K et al. (2015). “Hallux valgus—a case for a physiotherapist or only for a surgeon? Literature review.” J Phys Ther Sci. 27(10):3303-7.

Robinson AH et al. (2005). “Modern concepts in the treatment of hallux valgus.” J Bone Joint Surg Br. 87(8):1038-45.