Inferior thoracic aperture
The inferior thoracic aperture connects the thorax with the abdomen.
On this page:
Gross anatomy
The inferior thoracic aperture is irregular in shape and is more oblique and much larger than the superior thoracic aperture. The diaphragm occupies and closes the inferior thoracic aperture, thereby separating the thoracic and abdominal cavities. For structures to pass between the two cavities, they either pass behind the diaphragm or pass through various diaphragmatic apertures.
Boundaries
- posteriorly: 12th thoracic vertebral body and transverse processes
- posterolaterally: 11th and 12th ribs
- anterolaterally: the costal margins formed by the conjoint costal cartilages of 7th to 10th ribs
- anteriorly: xiphisternal joint
Contents
Apart from the diaphragm, the list of structures that pass through the inferior thoracic outlet is best described by considering the various diaphragmatic apertures:
- aortic hiatus (T12) (not a true aperture)
- esophageal hiatus (T10)
- vena caval foramen (T8)
- lesser apertures
Related Radiopaedia articles
Anatomy: Thoracic
- thoracic skeleton
- thoracic cage
- thoracic spine
- articulations
- muscles of the thorax
- diaphragm
- intercostal space
- intercostal muscles
- variant anatomy
- spaces of the thorax
- thoracic viscera
- tracheobronchial tree
-
lungs
-
bronchopulmonary segmental anatomy (Boyden Classification) (mnemonic)
- left lung
- right lung
- variant anatomy
- lung parenchyma
- hilum
- pleura
-
bronchopulmonary segmental anatomy (Boyden Classification) (mnemonic)
-
heart
- cardiac chambers
- heart valves
- pectinate muscles
- cardiac fibrous skeleton
- coronary arteries
- innervation of the heart
- fetal circulation
-
pericardium
- pericardial space
- oblique pericardial sinus
- transverse pericardial sinus
-
pericardial recesses
- aortic recesses
- pulmonic recesses
- postcaval recess
- pulmonary venous recesses
- pericardial ligaments
- epicardial fat pad
- esophagus
- thymus
- breast
- blood supply of the thorax
- arteries
-
thoracic aorta (development)
- ascending aorta
- aortic arch
- aortic isthmus
- descending aorta
- pulmonary trunk
-
thoracic aorta (development)
- veins
- superior vena cava (cavoatrial junction)
- inferior vena cava
-
coronary veins
- cardiac veins which drain into the coronary sinus
- great cardiac vein
- middle cardiac vein
- small cardiac vein
- posterior vein of the left ventricle
- vein of Marshall (oblique vein of the left atrium)
- anterior cardiac veins
- venae cordis minimae (smallest cardiac veins or thebesian veins)
- cardiac veins which drain into the coronary sinus
- pulmonary veins
- arteries
- lymphatics
- innervation of the thorax