manubriosternal

The manubriosternal joint, also known as the sternal angle or angle of Louis, is a cartilaginous articulation located at the junction of the manubrium and the body of the sternum. This anatomical landmark is situated approximately at the level of the second thoracic vertebra and serves as a key reference point in medical imaging and clinical assessments.

The joint is formed by the fusion of the manubrium sterni, the upper portion of the sternum, and the body of the sternum, which is connected via the costal cartilages of the first pair of ribs. This connection allows for limited movement, primarily in the anterior-posterior direction, which can be influenced by factors such as respiration, posture, and certain pathological conditions.

In clinical practice, the manubriosternal joint is often used as an anatomical landmark for measuring distances, such as in the assessment of cardiac and thoracic dimensions. It also plays a role in identifying the position of the aortic arch, which typically arches over the joint. The joint can be palpated at the sternal notch, a prominent depression located at the superior aspect of the manubrium.

Structural variations or abnormalities at the manubriosternal joint may occur due to congenital defects, trauma, or degenerative changes. Conditions such as sternal fracture, sternal separation, or sternoclavicular dislocations can affect this region, potentially leading to pain, instability, or other symptoms. Additionally, the joint may be involved in conditions affecting the thoracic cavity, such as thoracic outlet syndrome or certain types of pneumothorax.

Research and clinical studies continue to explore the functional significance and potential implications of the manubriosternal joint in both normal physiology and pathological states.