Protruding thoracic ribs may be due to several reasons: i. It may be caused by the patient being too thin. This condition is seen in patients who are overly dieting to lose weight or have severe wasting diseases, like tumors, tuberculosis, diabetes, etc. At this time, the patient’s subcutaneous fat is too thin, which will make the bony protrusion in this area become more obvious. Second, it may be caused by the deformity related to the thorax. For example, when a patient has scoliosis, or lung disease like slow lung obstruction, or rickets, it may lead to various deformities of the thorax. In this case, the rib cage will become very prominent and obvious at a certain place. Third, it may be caused by old injuries. For example, if the patient has had a previous old fracture here, there may be excessive osteophytes here during their recovery process, causing this area to become more prominent. Fourth, it may be due to rib exostosis. This condition is caused by the patient’s excessive thinness and prolonged abdominal tightening, resulting in bilateral protrusion of the rib cage, especially in the rib arch area.