What distinguishes true ribs from false ribs?

True ribs are distinguished from false ribs primarily by their direct connection to the sternum. The true ribs, which consist of the first seven pairs of ribs, have individual costal cartilages that attach directly to the sternum, allowing for a more stable and direct bony connection to the central thoracic structure. This direct articulation is significant for structural integrity and respiratory mechanics.

In contrast, false ribs, which include the 8th through 12th pairs, do not have this direct attachment; instead, their costal cartilages may either connect indirectly to the sternum or not at all (as seen in the floating ribs). Understanding this distinction is essential for grasping the overall function and anatomy of the rib cage, which plays a critical role in protecting vital organs within the thoracic cavity and facilitating the mechanics of breathing.