Twelfth thoracic vertebra: anatomy, location and function

Also called

T12

What it is

The twelfth of the twelve thoracic vertebrae, labelled T12, which articulate with ribs.

Location

Lies at the thoracolumbar junction between T11 and the first lumbar vertebra (L1).

Function

Supports the trunk, forms the posterior part of the rib cage by articulating with ribs, and protects the spinal cord.

Body system

Skeletal · single, midline structure

FMA ID

FMA10081 (Foundational Model of Anatomy)

Key facts

• Transitional vertebra: its upper articular processes face like thoracic ones, but its lower ones face outward like lumbar ones.
• Carries a single costal facet for rib 12, a floating rib; the aortic hiatus of the diaphragm lies at about T12.

Clinical relevance

The thoracolumbar junction is a common site of compression and burst fractures after trauma.

The nearest named structures in the 3D model, measured from the centre of each part:

• Eleventh thoracic vertebra · skeletal
• Intervertebral disk of eleventh thoracic vertebra · skeletal
• First lumbar vertebra · skeletal
• Suprarenal vein · cardiovascular
• Middle suprarenal artery · cardiovascular
• Hemiazygos vein · cardiovascular
• Intervertebral disk of first lumbar vertebra · skeletal
• Descending aorta · cardiovascular
• Intervertebral disk of tenth thoracic vertebra · skeletal
• Adrenal gland · endocrine