The sternum, costal cartilage and some ribs are depressed toward the spine, forming a funnel-shaped deformity. The sternum of most funnel-shaped pectoral muscles starts at the level of the second or third costal cartilage, reaches the lowest point slightly higher than the xiphoid process, and then returns to form a boat-shaped deformity. The two sides or outer sides are depressed and deformed inward, forming the two side walls of funnel chest. The rib inclination of funnel chest is larger than normal, and the rib suddenly droops from the upper back to the lower front, making the front and back closer. In severe cases, the deepest depression of sternum can reach chiropractic. The deformity of young patients with pectus excavatum is often symmetrical. With the increase of age, the pectus excavatum deformity is gradually asymmetrical, the sternum often rotates to the right, the right costal cartilage depression is often deeper than the left, and the right breast development is worse than the left. The posterior chest is mostly flat or round, and scoliosis gradually increases with age. Scoliosis is not easy to occur when young, and it is more obvious in patients after puberty. The pectus excavatum deformity compresses the heart and lungs, and most of the heart transfers to the left chest cavity. Children often show a unique weak posture: the neck stretches forward, the shoulders are round, and the stomach is pot-shaped.