CausesBy Mayo Clinic staff
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Bunions develop when the pressures of bearing and shifting your weight fall unevenly on the joints and tendons in your feet. This imbalance in pressure makes your big toe joint unstable, eventually molding the parts of the joint into a hard knob that juts out beyond the normal shape of your foot.
Causes of bunions include:
- High-heeled or ill-fitting shoes
- Inherited foot type
- Foot injuries
- Deformities present at birth (congenital)
Bunions may be associated with various forms of arthritis, including inflammatory or degenerative forms, causing the protective cartilage that covers your big toe joint to deteriorate. An occupation that puts extra stress on your feet or one that requires you to wear pointed shoes also can be a cause.
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