Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

Which ribs are classified as 'false' ribs?

1. Ribs 1-5

2. Ribs 6-12

3. Ribs 8-10

4. Ribs 11-12

The correct answer is: Ribs 8-10

False ribs are classified specifically as those ribs that do not directly attach to the sternum via their own costal cartilage. Instead, they either attach indirectly or do not attach at all. Ribs 8 through 10 are referred to as false ribs because they connect to the sternum through the costal cartilage of the rib above them (they share connections, rather than having direct attachments to the sternum). In contrast, true ribs (ribs 1-7) have a direct connection to the sternum, while the floating ribs (ribs 11-12) are considered false ribs as well, but they do not connect to the sternum at any point. Therefore, the classification of ribs 8-10 as false ribs accurately reflects their indirect attachment to the sternum, making this answer correct in the context of rib classification.