Inferior mediastinum

The inferior mediastinum is the box-shaped space in the mediastinum below the transthoracic plane of Ludwig between the wedge-shaped superior mediastinum above and the diaphragm and inferior thoracic aperture below. There are no physical structures that divide the superior and inferior mediastina therefore pathological processes can freely involve both spaces.

The inferior mediastinum is further compartmentalised by the fibrous pericardium into:


  • superiorly: transthoracic plane of Ludwig
  • inferiorly: diaphragm and inferior thoracic aperture
  • laterally: mediastinal pleura and lungs
  • anteriorly: body of the sternum
  • posteriorly: bodies of lower eight thoracic vertebrae, their transverse processes and associated ribs