L-spine: Radiologic anatomy

Anatomy, Basic, Basic Sciences

In a typical adult, the spinal cord terminates at L1 (L3 in infants). The L4/5 interspace, the site often used for spinals and epidurals, is typically at the level of the iliac crest.

Normal oblique view of L spine: “Scotty Dog Sign”

  • Transverse process: nose
  • Pedicle: eye
  • Inferior articular facet: front leg
  • Superior articular facet: ear
  • Pars interarticularis: neck 

This view can be utilized when attempting to complete a medial branch nerve block. The nerve typically lies at the junction of the transverse process and the superior articular process.

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2019

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2014

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Author
Chris Racine, MD