Leg pattern asymmetry refers to the phenomenon that the leg pattern around the whole thigh and knee joint of the infant just after birth occurs asymmetrically on the left and right sides, and this situation has the following two possibilities: First, because the infant’s nutrition is better, the fat and muscles on the top of the lower limb legs develop better before the infant is born, but the development appears relatively asymmetrical, which will trigger the phenomenon of leg pattern asymmetry. This phenomenon is normal, and there is no other deformity of the leg, or limited movement of the hip joint of the thigh. Second, relatively serious is the occurrence of congenital abnormal development of the hip joint in children, whether it is congenital dislocation of the hip joint or abnormal development of the hip joint, dysplasia, will lead to the phenomenon of asymmetric leg lines in infants. In addition to leg pattern asymmetry, there is also the symptom that one side of the hip joint cannot be abducted, that is, both sides of the leg cannot be separated at the same angle at the same time, and the angle of movement of one side of the thigh is relatively small, this situation will also appear leg pattern asymmetry phenomenon.