Ribs vs. Sternum

Attribute	Ribs	Sternum
Location	Attached to the thoracic vertebrae	Located in the center of the chest
Number	12 pairs	1
Shape	Curved	Flat
Function	Protect the organs in the chest cavity	Support the rib cage and protect the heart and lungs

Structure

Ribs and sternum are both important components of the human skeletal system. Ribs are long, curved bones that form the rib cage, providing protection to vital organs such as the heart and lungs. There are 12 pairs of ribs in the human body, with the first seven pairs known as true ribs and the remaining five pairs as false ribs. The sternum, on the other hand, is a flat bone located in the center of the chest. It consists of three parts: the manubrium, the body, and the xiphoid process.

Function

The primary function of ribs is to protect the organs in the thoracic cavity, such as the heart and lungs, from external trauma. Ribs also play a crucial role in respiration by expanding and contracting to allow for the inhalation and exhalation of air. The sternum, on the other hand, serves as an anchor point for the ribs and muscles of the chest. It also helps to protect the heart and lungs and plays a role in the production of red blood cells in the bone marrow.

Location

Ribs are located on either side of the thoracic cavity, extending from the spine to the sternum. They are attached to the thoracic vertebrae at the back and to the sternum at the front. The sternum, as mentioned earlier, is situated in the center of the chest, connecting to the ribs via cartilage. It forms the front part of the rib cage and is easily palpable in the midline of the chest.

Shape

Ribs are long, curved bones that are somewhat flat in shape. They have a slight twist along their length, which helps to provide flexibility and allow for the expansion of the chest during breathing. The sternum, on the other hand, is a flat bone that is roughly T-shaped. The manubrium is the top portion of the sternum, followed by the body in the middle, and the xiphoid process at the bottom.

Articulation

Ribs articulate with the thoracic vertebrae at the back and with the sternum at the front. The true ribs (first seven pairs) connect directly to the sternum via costal cartilage, while the false ribs (remaining five pairs) either attach indirectly to the sternum or do not attach at all. The sternum articulates with the clavicles at the top and with the costal cartilage of the ribs below.

Development

Ribs and sternum develop from different embryonic structures. Ribs arise from the somites, which are blocks of mesoderm that give rise to the musculoskeletal system. The sternum, on the other hand, develops from the fusion of multiple segments of cartilage known as sternal bars. These bars eventually fuse together to form the complete sternum during fetal development.

Injuries

Ribs are more prone to fractures than the sternum due to their curved and relatively fragile nature. Rib fractures can occur as a result of trauma, such as a fall or a direct blow to the chest. Sternum fractures are less common but can occur in high-impact accidents, such as car crashes. Both rib and sternum fractures can be painful and may require medical intervention depending on the severity of the injury.

Conclusion

In conclusion, ribs and sternum are both essential components of the human skeletal system that play a crucial role in protecting vital organs and supporting the chest cavity. While ribs provide flexibility and protection to the thoracic organs, the sternum serves as an anchor point for the ribs and muscles of the chest. Understanding the similarities and differences between ribs and sternum can help in diagnosing and treating injuries to the chest and thoracic region.