Chest pain in noncardiac or nonheart related situations can cause a burning sensation behind your breastbone (your sternum), according to the Mayo Clinic.
Noncardiac conditions that may be the culprit include a musculoskeletal syndrome called Tietze, which is also known as costochondritis. If you have this problem, the cartilage in your rib cage, particularly those that join your breastbone to your ribs, becomes inflamed.
Costochondritis causes pain in the chest and will worsened when you push on your ribs near the sternum or on your sternum. Those suffering from fibromyalgia often have to deal with costochondritis.
Heartburn can result in a painful, burning sensation behind your sternum (breastbone). Heartburn happens when acid from your stomach washes up and into the esophagus, which is a tube that runs from your stomach to your throat.
If the pain in your sternum worsens when you eat spicy food, drink beverages that contain caffeine or when your stomach is empty, you may have a gastric ulcer, gastritis or GERD, which is gastroesophageal reflux disease.
GERD is a digestive disease that is chronic. The backwash or stomach acid and bile irritates your esophagus and causes pain.