Chest depression is mainly a manifestation of inward collapse of the sternum and surrounding bones, which causes the corresponding condition, and the common causes mainly include rickets, rib fracture and funnel chest. 1. Rickets: mainly related to calcium deficiency, the lack of calcium itself leads to bone softening, which will cause the thoracic collapse and further lead to the symptoms of chest depression. 2. Rib fracture: multiple fractures of the ribs and misalignment of the fractured ends can easily lead to flail chest, which can cause the collapse of the thorax and lead to the production of chest depression. 3. Funnel chest: the sternum, together with the ribs, is sunken inward or backward to form a boat-shaped or funnel-shaped deformity, usually the deepest at the junction of the body of the sternum and the xiphoid process, which is the most common chest wall deformity. When chest depression is accompanied by obvious abnormal respiratory conditions, wheezing and other symptoms, it is necessary to consult a doctor in time, diagnose the specific cause of the disease through clinical examination, and carry out standardized treatment under the guidance of the clinician to avoid delaying the condition.