Mnemonic

Thoracic Inlet Contents

A memory aid for the structures passing through the superior thoracic aperture.

Expansion

Trachea and oesophagus centrally, with vessels and nerves on either side

Expansion

Bounded by the body of T1, the first ribs and the upper border of the manubrium, the inlet transmits:

  • Trachea and oesophagus, in the midline
  • Apices of both lungs with their cervical pleura
  • Common carotid and subclavian arteries
  • Brachiocephalic and internal jugular veins
  • Vagus, phrenic and recurrent laryngeal nerves
  • Sympathetic trunks
  • Thoracic duct, on the left

It is a crowded space, which is why an apical lung tumour can simultaneously involve the sympathetic chain (Horner syndrome) and the lower brachial plexus (T1 wasting of the small muscles of the hand).