There are two types of pheochromocystis congenita and acquired. A small number of children’s chicken chest is congenital, while the acquired chicken chest is caused by rickets, the specific reasons are as follows: 1, congenital developmental abnormalities: congenital chicken chest and funnel chest deformity as with genetics, the family has a chest wall deformity chicken chest incidence is significantly higher in the fetus or infancy, the development of the sternum and spinal bones, ribs imbalance, resulting in thoracic deformity; 2, acquired factors: (1) malnutrition. After birth, infants and children do not get enough nutrition, suffering from certain malnutrition diseases, such as pediatric rickets, for a long time can affect the development of the sternum, resulting in thoracic deformity; (2) secondary to diseases in the thoracic cavity: such as certain congenital heart disease, the enlarged heart compression of the chest wall, resulting in chicken chest deformity, flat chest deformity due to chronic abscess, long-term chronic respiratory infections can cause a weakened respiratory function, in order to meet the respiratory In order to meet the respiratory needs, the diaphragm movement is strengthened, pulling the Hao’s sulcus inward, gradually forming the chicken chest deformity, also secondary to heart or chest surgery.