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 overlap
• Persistent or intermittent pain
• Restricted movement of your big toe if arthritis affects the toe

There are many theories about how bunions develop, but the exact cause is unknown. Factors likely include:

• Inherited foot type
• Foot injuries
• Deformities present at birth (congenital)

Experts disagree on whether tight, high-heeled or too-narrow shoes cause bunions or whether footwear simply contributes to bunion development.

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 susceptible to bunions.
• Rheumatoid arthritis. Having this inflammatory condition can make you more susceptible to bunions.
• Heredity. The tendency to develop bunions might be because of an inherited structural foot defect.

Although they don't always cause problems, bunions are permanent unless surgically corrected. Possible complications include:

• Bursitis. This painful condition occurs when the small fluid-filled pads (bursae) that cushion bones, tendons and muscles 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 inflammation in the ball of your foot.