Tight-fitting shoes are thought to be the cause of bunions in most patients. Shoes such as high heels or cowboy boots are particularly damaging to the toes. These shoes have a sloping foot bed and a narrow toe box. The slope causes the front of the foot to be pushed with force into the narrow toe box, causing the toes to become squeezed together. Depending on factors such as duration of wearing constraining footwear, skeletal maturity, and individual factors, the toes can become adapted to the new position and lead to the deformity we know as a bunion.
Footwear is not the only cause of a bunion. Genetics do play a significant role, and people who have bunions in the family are also much more likely to have bunion than people who do not. Injuries to the foot can also be a factor in developing a bunion. Many people who have a bunion have a combination of factors that makes them susceptible to having this condition. For example, women over the age of forty who have a family history of bunions, and often wear high-heeled shoes, would be considered likely to develop a bunion.
How Important Are Shoes?It's difficult to know exactly how important footwear is in the development of bunions, but we know it is the only variable we can significantly control. Bunions are much less common in countries without Western footwear. Bunions occur in non-Western countries in about 3% of the population. In countries with Western footwear, the prevalence of bunions is over 30%. In countries where Western footwear has been introduced recently, the prevalence of bunions has risen to coincide with rates seen in Western countries.
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