Costochondral joints

These joints connect the ribs to the costal cartilages, contributing to the flexibility of the rib cage.

Costochondral joints are the junctions between the costal cartilages and the ribs. They are classified as synarthrodial joints, meaning they permit very limited movement. These connections allow for slight movement during respiration, helping to expand and contract the thoracic cavity.

Terminologia Anatomica

articulatio costochondralis

System

Skeletal system

Function

The primary function of costochondral joints lies in their role in respiration. During inhalation, the rib cage expands, and this movement is facilitated by the flexibility provided by the costochondral joints. When taking a breath, the muscles between the ribs (intercostal muscles) contract, lifting the ribs and allowing the ribs to pivot slightly at these joints. This process increases the volume of the thoracic cavity, leading to a decrease in pressure that draws air into the lungs. Additionally, these joints play a role in protecting vital thoracic organs, such as the heart and lungs, by maintaining the structural integrity of the rib cage while allowing for necessary mobility.

Location

Costochondral joints are located along the anterior (front) part of the thoracic cage. They can be found where each true rib (ribs 1 to 7) meets its corresponding costal cartilage. These ribs articulate directly with the sternum through their costal cartilages. Importantly, the costochondral junctions are situated in the upper half of the rib cage, with the most notable presence at the junctions of the first rib and its costal cartilage, followed by the subsequent ribs down to the seventh rib. This position is crucial in allowing flexibility and expansion during breathing cycles.

Did You Know?

The first costochondral joint is typically the least mobile, providing stability to the thoracic architecture.
Costochondritis, an inflammation of these joints, can lead to chest pain that mimics heart-related issues.
These joints are key in ensuring that the rib cage expands during deep breaths, making them essential for proper lung function.