The sternal stalk is parallel to the anterior midline of the body and does not protrude, once it does, it may be related to the following reasons: 1, thoracic deformities, such as some patients have congenital hereditary diseases, such as scoliosis, resulting in thoracic deformities, or in the acquired growth and development of malnutrition, resulting in rickets, resulting in thoracic deformities, such as chicken chest, funnel chest. 2, old injury to the sternum, such as old fracture of the sternum, then after recovery, there may be a deformity, or due to excessive bone growth, which is manifested as a protrusion. 3, too thin, in some malnourished patients, it is possible that the subcutaneous fat is very thin, or the muscle here is very thin, which leads to the sternal stalk looks more protruding. 4, heart-related diseases, such as hypertrophy of the heart, a large number of pericardial effusion, may also appear this condition.