Funnel chest is a deformity in which the sternum, rib cartilage and part of the rib cage are depressed toward the spine to form a funnel shape. In funnel chest, the rib alignment slope is larger than normal, and the rib cage is depressed sharply from the upper back to the lower front, making the front and back closer together. In young patients with funnel chest, the deformity is often symmetrical, but with age, the deformity gradually becomes asymmetrical, the sternum tends to rotate to the right, the depression of the right rib cartilage tends to be deeper than the left, and the right breast development is worse than the left. The posterior chest is mostly flat-backed or round-backed, and scoliosis gradually worsens with age; scoliosis is less likely to occur when the patient is younger, and is more pronounced after puberty. The funnel chest deformity compresses the heart and lungs, and the heart is mostly displaced to the left side of the chest. Children often present with a distinctive frail posture: forward neck, rounded cut shoulders, and a cankered abdomen. The clinical use of funnel index to determine the degree: vFI = (a × b × c) ÷ (A × B × C) a. longitudinal diameter of the funnel chest depression; b. transverse diameter of the depression; c. depth of the depression; A. length of the sternum; B. transverse diameter of the thorax; C. shortest distance from the angle of the pectoralis muscle to the vertebrae Simple determination can be made by injecting water in the funnel to calculate the amount of water or calculating the deepest part of the funnel to determine the degree, but of course these alone are not enough Of course, this is not enough. The classification of funnel chest: v Severe: FI > 0.3 v Moderate: 0.3 > FI > 0.2 v Mild: FI < 0.2 Surgery should be considered for moderate and above. Mild can be observed and does not require special treatment. A mild funnel chest can be asymptomatic, while a more severe deformity may produce compression symptoms on the heart and lungs, or even seriously affect respiratory and circulatory functions. Young children may develop recurrent respiratory infections with cough and fever. Some patients may also develop cardiac arrhythmias, as well as systolic murmurs. Traditional treatments for funnel chest mostly involve amputation of the rib cartilage and then reshaping to repair the deformity, which is very invasive. NUSS surgery is a popular minimally invasive treatment for funnel chest, in which a special plate is inserted behind the sternum, and the lateral ribs are used to support the central depressed rib cartilage, lift the sunken anterior chest wall, and use the regeneration of rib cartilage and the remodeling of regenerated rib cartilage to complete the orthopedic surgery of funnel chest, which is significantly less invasive.