Supernumerary ribs

Last revised by Daniel J Bell on 28 Jun 2021

Supernumerary ribs occur most commonly as a cervical rib arising from C7 or a lumbar rib arising from L1. In extremely rare situations, there can be sacral, coccygeal, intrathoracic, or aberrant lumbar ribs 3. Rarely supernumerary ribs (cervical and lumbar ribs aside) have been found as 'normal' anatomic variants, without evidence of any clinical sequelae.

Epidemiology

Associations

Supernumerary ribs have been used as a marker for developmental toxicity bioassays in test animals 2.

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