suprapleural membrane

Last reviewed 01/2018

The suprapleural membrane is a strong fascial connective tissue layer overlying the apices of the lungs above the superior thoracic inlet on each side. It can be considered as an extension of the tendinous insertion of the scalenus minimus muscle. It slopes down at the same oblique angle to the horizontal as the inlet.

Its attachments include:

  • anteriorly: 1st costal cartilage, deep surface of first rib
  • laterally: first rib
  • medially: merges with mediastinal pleura projecting inferiorly
  • posteriorly: transverse process of C7 vertebra

Inferiorly is the parietal pleura of the lung apices. Superiorly, are the structures at the base of the neck e.g. the subclavian vessels.

The purpose of the suprapleural membrane is to act as a rigid barrier so as to prevent changes in intrathoracic pressure drawing upon the contents of the neck.