Sternocostal joints

The primary function of the sternocostal joints is to provide flexibility and movement to the thoracic cage, which is essential for respiration. During inhalation, the rib cage expands as the diaphragm contracts, and the sternocostal joints allow the ribs to elevate and widen, facilitating air intake. Conversely, during exhalation, the rib cage returns to its resting position, aided by the elastic nature of ligaments and the sternocostal connections. Additionally, these joints stabilize the anterior thoracic wall, protecting vital organs housed within the thoracic cavity, such as the heart and lungs, while also supporting the muscles involved in respiration.

The sternocostal joints are located in the anterior region of the thoracic cage. Specifically, they are situated where the true ribs (the first seven pairs) join the sternum, which is positioned centrally in the chest. The first joint can be found just below the manubrium, while the subsequent joints extend down to the body of the sternum. This arrangement places the sternocostal joints at the interface between the rib cage and the sternum, contributing to the overall structural integrity and mobility of the thoracic area.

• The first sternocostal joint is unique because it is a cartilaginous joint, providing little to no movement compared to the other joints in this group.
• The movement at sternocostal joints is crucial for breathing; without this flexibility, the expansion of the lungs would be severely hindered.
• In some individuals, age and degenerative changes can lead to stiffness in the sternocostal joints, impacting respiratory efficiency.