Pain inside the rib cage above the left breast is part of the differential diagnosis of chest pain, which is relatively more aggressive at this time, as the rib cage above the left breast produces clinical signs of high-risk chest pain. Male patients will present with aortic coarctation, left-sided tension pneumothorax, acute coronary syndrome, etc. If men have intermediate risk chest pain, acute myocardial ischemia, unstable angina pectoris, left pleural effusion, left lung infection and other diseases will be present inside the ribs above the left breast. In men, the mild risk factors for pain inside the rib cage above the left breast may be left-sided costochondritis, costochondritis and herpes zoster, etc. In women, in addition to the above diseases, there may be left-sided lobular hyperplasia of the breast and left-sided acute mastitis.