The sternum, also known as the breastbone, is the flat bone that starts from base of the neck to just above the abdomen at front of the chest. It is made up of three main parts- the manubrium, the body of the sternum and the xiphoid process. The manubrium is the uppermost part. It has a dip near the base of the neck called the sternal notch. This dip creates two knots that can feel like lumps but are normal. The body of the sternum is the longest and middle part. It has several notches along its length on which ribs attach. At bottom-most part of the sternum, a small projection known as the xiphoid process occurs.
A lump or swelling can occur on or in the sternum. In most cases, the mass will not form a visible bulge but can be felt. Hernias and xiphoid process disorders are the most common causes of sternum lumps. Any mass on the sternum need to be investigated medically as it could be a sign of a serious disease or infection.
Symptoms of lump on, below and under sternum
The symptoms that will accompany a lump on or under sternum will depend on what is causing the lump. General ones include:
- pain in the chest or sternum
- difficulty breathing
- skin redness
- tenderness or warmth on the affected region
- swollen lymph nodes
See your doctor if such symptoms are to appear around the same time a sternal lump appears.
Lump below sternum or in lower sternum; xiphoid process
Not many people are aware of the presence of the xiphoid process. It is a downward-pointing bony projection located at the lowest part of the sternum. Your diaphragm and some abdominal muscles are partly attached to this structure. A lump at bottom of sternum is often caused by xiphoid process pain and swelling.
The xiphoid process naturally forms in a vertical manner. It can sometimes bend to create a lump below the sternum. This is commonly seen in obese or overweight individuals. Normally, this lump will not create any problems or pain. Some people will however experience pain and discomfort, especially after having a filling meal or when lifting heavy objects.
In early stages of development, the xiphoid process is composed of cartilage. The cartilage hardens and develops to form a bone. Injuries around the lower part of the chest can easily cause damage to this structure or even break it off. Severe injuries can be quite dangerous and with symptoms such as difficulty breathing, abdominal pain and nausea but not death.
If a lump on xiphoid process is not painful, it can be left without treatment. A bend in this structure can for example become more noticeable after losing weight. Mild injuries only require physical therapy and home treatment such as cold compress. A large or painful lump such as due to broken xiphoid process requires surgical treatment. In some cases, the small bone can be removed completely.
Large lump below sternum above belly button; Epigastric hernia
A large lump below the sternum can be an epigastric hernia. Epigastric hernias appear as large lumps on the abdominal wall, below the sternum and above belly button. This occurs when an abdominal mass pushes through a weak spot on the abdominal wall.
In most cases, epigastric hernias do not cause any symptoms and are painless. Some people may however experience chest pain, and tenderness below sternum. They tend to enlarge when coughing, laughing or lying on your stomach. If you notice signs such as fever, vomiting, severe abdominal pain and difficulty breathing, seek medical help immediately. Epigastric hernias can cause bowel blockage.
Hernias do not resolve on their own unless treated surgically. The good thing is that surgical treatment for hernias is not complicated. In fact, you may be released on the same day after the surgery.
At home, try measures such as not lifting heavy objects and taking frequent rather than heavy meals.
Lump under sternum causes
A lump under the sternum is commonly caused by gastroesophageal reflux disease (GERD) or heartburn. It results from frequent leakage of stomach acid and contents into esophagus. Esophagus is the tube that connects your throat with the stomach. It lies behind the sternum.
Acidic contents from the stomach irritate the lining of esophagus. As a result, scar tissue forms as part of natural healing process. This constricts the esophagus and can sometimes be felt as a lump especially when swallowing. Lower esophageal muscles may also constrict in attempt to stop acid leakage from the stomach.
The most common symptoms of GERD are chest pain and burning sensation in the chest that mostly occurs after eating. Mild cases do not require treatment. They can be managed with lifestyle changes or stretches such as lifting your legs with your back lying on a flat surface. OTC medications are also available for mild GERD management.
If it gets to a point of causing severe chest pain, difficulty breathing or feeling like there is a lump under the sternum, see your doctor.
Painful lump in middle of sternum causes
A painful lump in middle of the sternum can originate in the bone itself or the tissues and tendons attached to it. Inflammation of muscles, tendons and skin layers in the middle of your chest is likely to cause a swollen lump rather than a hard one. This will resolve after several days.
Fractured sternal bone is more serious and painful. The lump that will result may not be visible unless felt by touch. Fractured bones usually call for medical treatment. Symptoms may include severe chest pain, vomiting and nausea.
Many cases of injuries on the clavicle are reported. The clavicle is also known as the collarbone. It is the flat bone that lies horizontally at the base of your neck. This bone is quite fragile and only reaches maturity after the teenage years. An injury on the clavicle’s medial end can extend to the sternum. Clavicle injuries are common causes of lump on top of the shoulder.
During the healing process, bones form hard lumps known as fracture calluses. These are normal lumps and do disappear after complete recovery.
Diseases and health conditions
- Costochondritis – this is inflammation of the sternum that occurs on the notches to which ribs are attached. It commonly occurs after an injury.
- Cellulitis – this is an infection that mostly occurs when outer skin layers break open. Deep cuts, open wounds and surgical procedures are potential risk factors.
- Osteomyelitis – osteomyelitis is a bone infection. Although not common on the sternum, it can occur after an accident or injury.
- Cancer – leukemia and bone cancer can cause sternal lumps. In most cases, cancerous lumps are hard and painless. It is not common to have cancer on sternum. See your doctor if you notice other masses such as a white lump on gums.
- Eesophagitis – this is inflammation of the esophagus. It can be sometimes felt as a lump under the sternum when swallowing.
- Swollen lymph nodes – several hundreds of lymph nodes occur all over your body. These lymph nodes swell when the immune system is fighting a disease or infection. Sometimes, lymph does will not form noticeable lumps. You can for example feel a lump on the back of a baby’s head which is not noticeable unless pressed on.
- Lipoma – lipomas are very common benign lumps that form under skin. They are soft, rubbery and movable when pressed with a finger. Lipomas can appear anywhere in the body. Subcutaneous lipomas are the common type which can be easily felt under the skin. Intermuscular lipomas develop much deeper and former larger lumps. A large lipoma lump in fatty tissue on the stomach may be felt as a lump under the sternum.
- Cysts – like lipomas, cysts are very common and benign lumps that develop under the skin. They are usually painless and slightly movable. Sebaceous cysts are most common. They can cause a lump behind the earlobe, on the chest, back, penis, vulva and so on.
- Hematoma – a hematoma is a blood clot that forms outside blood vessels. Forms of injuries such as being hit with a blunt object can damage blood vessels without breaking outer skin layers. As a result, blood may leak and clot under the surrounding tissues. You can also have a hematoma painful lump in the scrotum after a vasectomy.
- Swelling of abdominal organs – growths can originate in many abdominal organs and tissues located in the upper quadrant under sternum. Most such growths are intolerably painful and commonly misdiagnosed. Signs of abdominal mass can appear elsewhere such as on the tongue or in the mouth. Imaging tests will be required during diagnosis of such lumps. Consider reading more on what does a lump in the stomach mean for more details.
Sometimes, medical diagnosis for a sternal lump may not point to any of the causes discussed here. The lump can also be a medical emergency that requires immediate treatment. It is for such reasons that you are advised to check with your doctor the moment you notice a mass in the sternal region.