Characteristics of adult flatfoot in the United States.

Many factors have been suggested to cause flatfoot deformity. The purpose of this study was to identify risk factors for flatfoot deformity, which itself can be a causative factor for other foot and ankle pathologies. The National Health Interview Survey (Podiatry Supplement) from 1990 was analyzed to determine associations of various demographic factors and other foot and ankle pathologies with self-reported flatfoot deformity. We found statistically significant (P <or= .05) associations of flatfoot with age, male gender, BMI, white-collar occupation, veteran status, bunion, hammertoe, calluses, arthritis, and poor health. Treatment and prevention of flatfoot may have an effect on an individual's overall health and occurrence of other foot and ankle pathologies.