The Thoracolumbar Spine

Fracture prevalence | Projections | Stability | Classification of trauma | Pathology

(hover over images to zoom, click to enlarge)
Learning outcomes
  • Assess skeletal radiographs using a systematic approach
  • Describe spinal anatomy
  • Understand the concept of stability and the 3 column concept
  • Understand mechanisms of injury and the likely fractures/dislocations which may result
  • Search for subtle injuries and understand their clinical significance
  • Understand common eponyms
  • Recognise potential ligament injuries
  • Recognise common pathological conditions seen around the spine
Fracture prevalence

Assess on both images:

  • Height of vertebral bodies should be equal.
  • Width of intervertebral disc spaces should be uniform.
  • Continuity of superior and inferior endplates: should remain unbroken.
  • Distance between spinous process should be equal.
  • Trace the posterior elements; the pedicles, laminae, and spinous processes.
Normal lumbar spine   Normal lumbar spine
Normal lumbar spine   Normal lumbar spine

Specifically on the AP image:

  • Soft tissue signs - Widening of the paraspinal line adjacent to the left side of the thoracic spine is indicative of a haematoma resulting from a fracture:
Paraspinal haematoma T4/5 dislocation
  • Pleural cap - Refers to a paraspinous haematoma, which dissects over lung apex.
  • Inter-pedicular distance. Should become gradually wider from L1 to L5.
  • Check for an "empty" vertebral body on the AP radiograph; the posterior elements should be superimposed.
  • Transverse processes should remain intact.

Specifically on the lateral image:

  • Malalignment. Trace the anterior, posterior and spinolaminar lines. If two of these lines are disrupted, the injury is considered unstable.
  • Posterior vertebral body cortex should be slightly concave.
Significance of Injury and the concept of stability
Classification of acute trauma
Fracture superior endplate L1   Anterior wedge compression fracture L1
(* author's own Xrays!)
Burst fracture
Abnormal interpedicular distance due to burst fracture   Convex posterior vertebral body cortex due to burst fracture
Chance fracture   Chance fracture
Fracture-dislocation L2/L3   Fracture-dislocation L2/L3
Fracture left L1 transverse process. Overlying bowel gas right L1 transverse process
Spondylosis thoracic spine   Spondylosis thoracic spine
Spondylosis lumbar spine   Spondylosis lumbar spine
= Transverse process
= Pedicle
= Superior facet
Front leg
= Inferior facet
Collar through neck
= Fracture

Scotty dog   Fracture pars interarticularis   Fracture pars interarticularis
Spondylolisthesis L5/S1 with pars defect
Paget's disease L2
Diffuse metastases   Diffuse metastases
Ivory vertebra L3   Ivory vertebra L3
Metastasis pedicle L3   Metastasis pedicle L3
Abdominal aortic aneurysm   Abdominal aortic aneurysm
Ankylosing spondylitis   Ankylosing spondylitis
Ankylosing spondylitis with fracture T8/T9   Ankylosing spondylitis with fracture T8/T9
Ankylosing spondylitis   Ankylosing spondylitis

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