Boundaries of the thoracic inlet





Posterior: Body of T1 vertebrae
Antero laterally: Medial borders of first ribs and their costal cartilages
Anteriorly: Superior end of the manubrium of the sternum



Contents: Structures joining thorax to upper limb and neck

  • Ducts : Trachea, esophagus, thoracic ducts

  • Vessels:Common Carotid and Subclavian arteries, Internal jugular and sub clavian veins

  • Nerves : Vagus, Phrenic, recurrent laryngeal and sympathetic chain

  • Apex of lungs and pleura



The inferior thoracic aperture


Posteriorly: T12 vertebra
Anterolaterally: 12 th pair of ribs and its costal cartilages

xiphisternal joint



Through this wide aperture (thoracic outlet), the thoracic cavity communicates with the abdomen. In the living, this outlet is closed by the thoracic diaphragm, which is pierced by the structures running between the abdominal and thoracic cavities.


The Chest Wall and Pleura