CorpusHuman Anatomy
SkeletalBone group

Thoracic vertebrae

Vertebrae thoracicae

Also known as: T1–T12, thoracic spine, dorsal vertebrae

The twelve vertebrae of the chest (T1–T12), characterised by costal facets on their bodies and transverse processes for articulation with the ribs.

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Overview

Number12
Atypical thoracic vertebraeT1, T10, T11, T12 (± T9)

Typical thoracic vertebrae (T2–T9) have heart-shaped bodies bearing superior and inferior costal demifacets for the heads of the ribs (each typical rib head articulates with its own vertebra and the one above), costal facets on the transverse processes (T1–T10) for the rib tubercles, a small circular vertebral foramen, and long spinous processes sloping steeply downward, overlapping the vertebra below like roof tiles (the tip of a mid-thoracic spinous process lies at the level of the body below).

The articular facets lie nearly in the coronal plane, on the arc of a circle centred on the vertebral body, which favours rotation and lateral flexion; flexion and extension are limited by the ribs, the sternum and the overlapping spinous processes. Atypical thoracic vertebrae: T1 (full facet for rib 1, demifacet for rib 2; cervical-like body), T10 (single facet for rib 10), T11 and T12 (single full facets; no transverse costal facets; T12 transitional with lumbar-type inferior facets — a common site of thoracolumbar fractures).

Location

Posterior thoracic wall, between C7 and L1.

Parts & subdivisions

  1. Costal demifacets on the body
    Articulate with the heads of the ribs (joints of the heads of ribs).
  2. Transverse costal facets
    T1–T10; articulate with rib tubercles (costotransverse joints).
  3. Long, inferiorly sloping spinous processes
    Overlap; limit extension.
  4. Coronal-plane facets
    Allow rotation.

Anatomy

Articulations

Ribs (costovertebral and costotransverse joints), adjacent vertebrae (discs and facet joints).

Function

  • Support the ribs and form the posterior thoracic wall
  • Protect the thoracic spinal cord
  • Permit trunk rotation

Clinical significance

Osteoporotic wedge fractures

Anterior compression of mid-thoracic and thoracolumbar bodies causes height loss and progressive kyphosis ("dowager’s hump"); often minimal trauma.

Thoracolumbar junction injury

T11–L2 is the commonest site of traumatic spinal fracture because the rigid thoracic segment meets the mobile lumbar segment (e.g. Chance flexion–distraction fractures with lap belts).

Compiled from standard anatomy and physiology references — see the Skeletal System sources. For education only; not medical advice.