Causes

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.