Superior thoracic aperture
The superior thoracic aperture, also known as the thoracic inlet or outlet, connects the root of the neck with the thorax.
The superior thoracic aperture is kidney-shaped and lies in an oblique transverse plane, tilted anteroinferiorly to posterosuperiorly. It is roughly 10 cm in transverse dimension and 5 cm in AP dimension.
- posteriorly: T1 vertebral body and costovertebral joints
- laterally: first ribs and their costal cartilages
- anteriorly: superior border of the manubrium
The list of structures that pass through the superior thoracic aperture is long and can be divided into five groups: midline, bilateral, posteriorly, and asymmetric left and right.
- midline from anterior to posterior
- laterally on both sides
- posteriorly from medial to lateral
- on the left:
- on the right
Variant structures that course through include:
- left vertebral artery from the aortic arch
- left brachiocephalic trunk
- right common carotid artery
- right subclavian artery
- right-sided thoracic duct