Superior thoracic aperture

Dr Henry Knipe ◉ ◈ et al.

The superior thoracic aperture, also known as the thoracic inlet or outlet, connects the root of the neck with the thorax.

Gross anatomy

The superior thoracic aperture is kidney-shaped and lies in an oblique transverse plane, tilted anteroinferiorly to posterosuperiorly.

Boundaries

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 outlet is long. Included below are the major structures:

viscera
- thymus
- trachea
- esophagus
- lung apices
vessels, nerves and lymphatics
- common carotid arteries
- subclavian arteries
- confluences of internal jugular and subclavian veins
- phrenic nerves
- vagus nerves
- recurrent laryngeal nerves
- thoracic duct
- sympathetic trunk
prevertebral fascia
muscles
- sternohyoid muscle
- sternothyroid muscle

Related pathology

thoracic outlet syndrome

Quiz questions

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