From the Research
The correct statement regarding surface anatomy of the thorax is "The manubriosternal joint is secondary cartilaginous and can be used to locate the transverse thoracic plane." This joint, also known as the sternal angle or angle of Louis, is formed by the articulation between the manubrium and body of the sternum. It is indeed a secondary cartilaginous joint (symphysis) and serves as an important clinical landmark. The transverse thoracic plane passes through this joint and corresponds to several important anatomical structures, including the second costal cartilage, the bifurcation of the trachea, and the beginning of the arch of the aorta. The other statements contain inaccuracies:
- the costal margin consists of the cartilages of ribs 7-10, not the floating ribs;
- ribs are better palpated laterally rather than at the midline posteriorly;
- and the apex of the lung extends above the first rib, not between ribs 2 and 3. Although the provided studies 1, 2, 3 do not directly address the question regarding surface anatomy of the thorax, general medical knowledge supports the statement about the manubriosternal joint. Key points to consider when evaluating surface anatomy of the thorax include:
- The manubriosternal joint is a reliable landmark for locating important structures
- The costal margin and rib palpation are important for assessing thoracic anatomy
- Understanding the relationship between the lungs and the thoracic cage is crucial for diagnosis and treatment of thoracic conditions.