Bunions are large, painful lumps occurring at the base of the big toe. They’re a very common foot deformity in the US, affecting approximately 35% of people aged over 65. The prevalence of bunions increases with age, but they’re most commonly associated with poor footwear.

That’s not stopped many people from wondering: “are bunions genetic?”

While most people understand that bunions are caused by ill-fitting shoes squeezing the toes together, what’s less appreciated is the underlying role of foot anatomy.

This post will explain if bunions are genetic, covering the most common causes and how to identify this debilitating condition.

  1. What is a bunion?

  2. How do bunions occur?

  3. Are bunions genetic?

  4. Other risk factors for bunion formation

  5. Treating bunions

What is a bunion?

A bunion, known medically as hallux abducto valgus, refers to a bony bump protruding from the base of the big toe. This bump isn’t an outgrowth of bone; rather, it’s the result of a deformity in the foot bones that causes the big toe to lean towards the second toe. The angle between the big toe and the foot produces the bump: the bigger the angle, the bigger the bump.

In addition to the bump, the signs and symptoms of a bunion include:

  • Red, inflamed skin over the bump

  • Calluses on the second toe

  • Foot pain, either intermittent or persistent

  • Difficulty moving the big toe

  • Uncomfortable to walk

  • Big toe bent towards the second toe.

How do bunions occur?

The true cause of bunions is debated. It’s generally agreed that ill-fitting or tight shoes play a key role in the progression of this condition. However, whether shoes cause bunions or only worsen an existing structural problem is still contested.

Certain conditions, like flat feet, excessively flexible ligaments, and abnormal bone structure, are thought to contribute to the development of bunions.

Whatever the “true” cause, bunions usually worsen over time. Factors that contribute to this decline include:

  • Tight or small shoes that pressure the big toe or force the toes together

  • High heels or pointy shoes that bunch the toes together

  • Prolonged standing

  • Arthritis in your feet

Are bunions genetic?

Probably. No specific genes have been identified that contribute to bunions. However, your natural foot shape – which is primarily inherited – is likely a major causative factor. If your parents suffered from bunions and you share their foot shape, there is probably an increased risk of you developing the condition.

Genetic factors rarely dictate if a condition will occur or not. For example, bunions may never occur if a person had a susceptible foot shape but also wore correct fitting shoes. In contrast, a person with a healthy foot shape may wear ill-fitting shoes and also never develop bunions.

Nevertheless, the risk of developing bunions is greater for first-degree relatives (siblings, parents, or children) of affected individuals compared to the public.

Other conditions that increase the risk of bunion formation include:

  • Hypermobility. The ligaments are loose and flexible, allowing the metatarsal bones to move more than usual.

  • Tight Achilles tendon. The tendon connecting the calf muscle to the heel bone is tight, changing how an individual walks and contributing to bunion formation.

Certain rare genetic syndromes that can affect bone development may also play a role, including Chitayat syndrome and fibrodysplasia ossificans progressiva.

Other risk factors for bunion formation

Genetic conditions and poor-fitting shoes aren’t the sole risk factors. Various conditions like osteoarthritis, inflammatory conditions (such as rheumatoid arthritis or psoriatic arthritis), and flat feet (pes planus) also increase the risk of the disabling condition.

Treating bunions

Bunions are diagnosed through visible inspection. Your podiatrist or doctor will inspect the foot and, if they suspect an injury or deformity, may send you for an x-ray. An x-ray will help gauge the severity of the bunion and identify its cause.

Treatment initially follows a conservative approach. Nonsurgical treatments include wearing special orthotics to prevent further progression, using over-the-counter (OTC) medication to soothe the pain, wearing OTC arch supports in your shoes, and taping the foot into a normal position.

If the nonsurgical treatment fails, surgery is the final option. The medical term for bunion removal is a bunionectomy. There are over 40 different types of bunionectomy. However, most involve removing the affected bone and the realignment of the toes. In the most severe cases, the joint may be replaced using plates and screws.

Recovery from a bunionectomy can take anywhere from two to four months, during which time you’ll need to wear a foot cast or boot.

If you’ve noticed a painful bump on the side of your foot, book an appointment with our expert podiatrists. We can treat the debilitating condition, getting you back on your feet.