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

Anteriorly:

  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.