Is the "eight-character step" positive or negative?
If you look at it yourself, it is an inverted word. The formation of flatfoot can be caused by congenital and acquired factors. Congenital factors include heredity and congenital deformation of skeletal muscles, and acquired factors include shortening of achilles tendon, inflammation and osteoarthritis. Other reasons may also lead to the formation of flat feet, for example, standing often causes the ligaments to bear the weight for a long time, stretching excessively to form flat feet, and even some people break the tendons of their feet because of overweight, which leads to flat feet, but this situation is rare.