Question

Where is the boundary between the superior and inferior mediastinum?

a) Between the thoracic vertebrae T4 and T5
b) At the level of the sternal angle
c) Between the diaphragm and the heart
d) Along the midclavicular line

Answer 1

The boundary between the superior and inferior mediastinum is at the level of the sternal angle, approximately where the thoracic vertebrae T4 and T5 are located.

Step-by-step explanation:

The boundary between the superior and inferior mediastinum is found at the level of the sternal angle. This landmark corresponds to where the manubrium meets the body of the sternum, which is approximately at the level of the thoracic vertebrae T4 and T5. The mediastinum is the central compartment of the thoracic cavity, containing the heart, enclosed in the pericardial cavity, as well as other vital structures. The superior mediastinum is separated from the inferior mediastinum by an imaginary horizontal line that extends from the sternal angle anteriorly to the intervertebral disc between T4 and T5 posteriorly.