Lumbar Rib

Description

CT images of the lumbar ribs. a VR image of the thoracolumbar spine and ribs with the sternum removed. Lumbar ribs are clearly shown (white arrows). b Axial multi-planar reconstruction (MPR) image of L1. Articulations between L1 and the lumbar ribs are well demonstrated (black arrows). c Coronal MPR image of the thoracolumbar vertebrae. L1 has bilateral costal articular facets for lumbar ribs (black arrowheads), unlike the characteristic transverse processes typically seen at this lower level

Name

• Lumbar Rib
• 13th Rib
• Supernumerary Lumbar Rib
• Lumbar accessory ribs

General

• Rare anatomical variant representing a transitional vertebrae at the thoracolumbar junction
• Prevalence is approximately 1%
• It presents as a rib coming off T13 or L1 depending on numbering classification
• Can be unilateral or bilateral
• Mostly asymptomatic incidental finding

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Clinical Significance

Surgical Considerations

• Can be misinterpreted on imaging studies
• Leading to diagnostic confusion or surgical errors

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See Also

• Accessory Bones Main
• Back Anatomy Main
• Radiology Main

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