A bunion is a bony bump that forms on the joint at the base of your big toe. It occurs when some of the bones in the front part of your foot move out of place. This causes the tip of your big toe to get pulled toward the smaller toes and forces the joint at the base of your big toe to stick out. The skin over the bunion might be red and sore.
Wearing tight, narrow shoes might cause bunions or make them worse. Bunions can also develop as a result of the shape of your foot, a foot deformity or a medical condition, such as arthritis.
Smaller bunions (bunionettes) can develop on the joint of your little toe.
The signs and symptoms of a bunion include:
- A bulging bump on the outside of the base of your big toe
- Swelling, redness or soreness around your big toe joint
- Corns or calluses — these often develop where the first and second toes rub against each other
- Ongoing pain or pain that comes and goes
- Limited movement of your big toe
When to see a doctor
Although bunions often require no medical treatment, see your doctor or a doctor who specializes in treating foot disorders (podiatrist or orthopedic foot specialist) if you have:
- Ongoing big toe or foot pain
- A visible bump on your big toe joint
- Decreased movement of your big toe or foot
- Difficulty finding shoes that fit properly because of a bunion
From Mayo Clinic to your inbox
There are many theories about how bunions develop, but the exact cause is unknown. Factors likely include:
- Inherited foot type
- Foot stress or injuries
- Deformities present at birth
Experts disagree on whether tight, high-heeled or too-narrow shoes cause bunions or whether footwear simply contributes to the development of bunions.
Bunions might be associated with certain types of arthritis, particularly inflammatory types, such as rheumatoid arthritis.
These factors might increase your risk of bunions:
- High heels. Wearing high heels forces your toes into the front of your shoes, often crowding your toes.
- Ill-fitting shoes. People who wear shoes that are too tight, too narrow or too pointed are more likely to develop bunions.
- Rheumatoid arthritis. Having this inflammatory condition can make you more likely to develop bunions.
- Heredity. The tendency to develop bunions might be the result of an inherited problem with the structure or anatomy of your foot.
Possible complications of bunions include:
- Bursitis. This painful condition occurs when the small fluid-filled pads that cushion the bones near your joints become inflamed.
- Hammertoe. An abnormal bend that occurs in the middle joint of a toe, usually the toe next to your big toe, can cause pain and pressure.
- Metatarsalgia. This condition causes pain and swelling in the ball of your foot.
To help prevent bunions, choose shoes carefully. They should have a wide toe box — no pointy toes — and there should be space between the tip of your longest toe and the end of the shoe.
Your shoes should conform to the shape of your feet without squeezing or pressing any part of your foot.
Nov 06, 2021
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