The Flat Foot.

In brief: The flat foot ranges in severity from imbalance caused by moderate forefoot varus to a hypermobile foot with ligamentous laxity and a plantar-flexed talus. Principal causes are soft-tissue or bony abnormalities and trauma or systemic disease. Treatment includes orthotic foot control and sometimes surgery. Sport shoes for people with pronated feet should have a very firm heel counter and should be moderately stiff.