In most cases, a popping or cracking sound in the sternum is not cause for alarm. Anyone who is unsure about the reason, on the other hand, should consult a doctor. This is especially significant if the sound is accompanied by other symptoms such as discomfort or edema. These might be symptoms of an injury or another health problem in the region. The sternum is the bone inside your chest that divides your thoracic cavity (where your heart and lungs are located) from your abdominal cavity (where your stomach is located). It may seem like just one bone, but it has multiple joints where it connects to ribs. The sternum is the strongest bone in the body, which means that it can take a lot of force before breaking. However, because it is so strong, it can also cover up serious injuries to other parts of your body. For example, if you get into a car accident and your sternum breaks, this could lead to complications unless treated by a medical professional immediately after the incident. A broken sternum can cause serious problems if not treated promptly. For example, air may enter your chest through the break, causing pain as well as other symptoms such as shortness of breath. If you delay seeking treatment for this condition, it could become much more severe or even life-threatening. Therefore, if you hear any kind of noise coming from your sternum, no matter how small, see a doctor immediately.