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Evidence. Clarity. Practice.

© 2026 OrthoVellum. For educational purposes only.

Not medical advice. Verify clinically important information against current local guidance.

Back to Research
Level IVMust KnowSpineClassification System

Evidence brief

Denis Three-Column Concept

The Three Column Spine and Its Significance in the Classification of Acute Thoracolumbar Spinal Injuries

Authors
Denis F
Journal
Spine
Year
1983

Key Findings

  • 1

    Anterior column: anterior 2/3 vertebral body, anterior longitudinal ligament

  • 2

    Middle column: posterior 1/3 vertebral body, posterior longitudinal ligament

  • 3

    Posterior column: posterior elements, ligamentous complex

  • 4

    Instability requires failure of middle column plus either anterior or posterior

  • 5

    Replaced two-column concept for thoracolumbar injuries

Clinical Implications

The three-column concept revolutionized understanding of spinal stability. Middle column involvement is key to determining instability and need for surgical stabilization.

Teaching Note

Draw the three columns on request. Key teaching point: middle column is the 'keystone' of stability. Burst fractures involve middle column (unstable), compression fractures do not (stable). Understand relationship to PLC integrity in TLICS.

Citation

Denis F. The three column spine and its significance in the classification of acute thoracolumbar spinal injuries. Spine. 1983;8(8):817-831.

PubMed

Evidence Level

IV

Level IV

Case series or case reports

Topics

thoracolumbarthree columnstabilityclassification

Related Topics

  • Thoracolumbar Fractures
  • Spinal Stability
  • Burst Fractures

External Links

View on PubMed

Related Papers

IV

TLICS Classification

Vaccaro AR (2005)

IV

SLIC Classification

Vaccaro AR (2007)

IV

Lenke Classification AIS

Lenke LG (2001)

IV

Levine-Edwards Classification

Levine AM (1985)