The difference between flat feet and normal feet is mainly manifested in the following aspects: First, there is an obvious difference in appearance. Flat feet will be flatter compared to normal feet, which is due to an obvious collapse of the arch of the foot, resulting in an obvious change in some of the normal protrusions of the dorsum of the foot. For example, if a patient compares a flat foot with a normal foot, he or she will find that the dorsum of the foot is flatter and flatter, and the forefoot is a little wider compared to a normal foot. In addition to this, some excessive bony elevation will be seen in the medial arch of the foot, such as the navicular tuberosity or the talonavicular process of the heel bone in this area will become more obvious compared to normal people. Secondly, there are functional differences, and patients with flat feet tend to have reduced motor ability, for example, the running and jumping ability of such patients is significantly reduced compared to normal people. Thirdly, patients with flat feet are more likely to develop foot-related diseases. After walking long distances or carrying large weights, these patients are often prone to tendonitis of the plantar area, or nerve irritation of the plantar area, or excessive osteophytes.