Popping or cracking sounds originating from the sternum can result from the sudden snapping of connective tissue, partial dislocation of a joint or trapped nitrogen bubbles releasing from joint fluid, according to Health Hype. Most popping sounds of the sternum relate to surrounding joints and are not a medical concern unless accompanied by pain, swelling or loss of mobility. Joint inflammation is a common cause and can subside on its own with rest and the use of anti-inflammatory drugs.
Other causes of popping and cracking sounds in the sternum include injury to the chest area, physical strain, costochondritis, Tietze’s syndrome, muscle spasms, osteoarthritis, rheumatoid arthritis and calcification of costal cartilage, states Health Hype. In cases of arthritis, a grating sound may accompany the popping and cracking due to erosion of the bone and joints. Accidents and sudden impacts are examples of chest trauma that can result in popping and cracking sounds, while unsafe or excessive weight lifting can lead to strain.
In cases of costochondritis, the costal cartilage connecting the ribs and sternum becomes inflamed due to infection, trauma or continual strain, explains Health Hype. While pain and tenderness are common, swelling does not frequently occur. The fourth and sixth ribs are the most frequent sites of costochondritis. Tietze’s syndrome, although similar to costochondritis, typically affects the second and third ribs and is more common in adolescent girls. Chronic coughing, vomiting and other forms of repetitive strain are likely causes.