posterior mediastinum (anatomy)

Last reviewed 01/2018

The posterior mediastinum is the region bounded by:

  • anteriorly:
    • and superiorly: the fibrous pericardium
    • and inferiorly: the posteroinferior surface of the diaphragm
  • posteriorly: the fifth to 12th thoracic vertebrae
  • superiorly: an arbitrary plane passing horizontally and posteriorly from the manubriosternal joint to the inferior border of the T4 vertebra
  • inferiorly: the sloping fibres of the diaphragm
  • laterally: posterior mediastinal surface of diaphragm

The key structures within the posterior mediastinum are the:

  • descending part of thoracic aorta
  • oesophagus
  • azygous system of veins
  • thoracic duct
  • thoracic sympathetic trunk