QS Study

The posterior mediastinum (or paravertebral compartment) is a potential space along the paravertebral sulci. It contains the descending aorta, thoracic duct, esophagus, azygos veins, and vagus nerves.

Posterior mediastinum Boundaries


  1. Bifurcation of the trachea.
  2. Pulmonary vessels.
  3. Fibrous pericardium.
  4. The posterior sloping surface of the diaphragm.

Posteriorly: Lower 8 thoracic vertebrae and intervening discs.

Superior: Transverse thoracic plane separating superior mediastinum from the inferior mediastinum.

Inferior: Diaphragm.

On each side: Mediastinal pleura.

Fig: Boundaries and Contents of Posterior Mediastinum

Contents – The posterior mediastinum contains a number of major organs, blood vessels, and nerves.

(i) Viscera: Oesophagus.

(ii) Arteries: Descending thoracic aorta & its branches.

(iii) Veins:

  1. Azygos vein.
  2. Hemiazygos vein.
  3. Accessory hemiazygos vein.

(iv) Nerves:

  1. Vagus.
  2. Splanchnic nerves.

(v) Lymph-nodes & vessels:

  1. Posterior mediastinal lymph nodes.
  2. Thoracic duct.