The posterior mediastinum is posterior to the pericardial sac and diaphragm and anterior to the bodies of the mid and lower thoracic vertebrae (see Fig. 3.57).
Its superior boundary is a transverse plane passing from the sternal angle to the intervertebral disc between vertebrae TIV and TV.
Its inferior boundary is the diaphragm.
Laterally, it is bordered by the mediastinal part of parietal pleura on either side.