False ribs

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Bone: False ribs
False ribs back.png
False ribs (shown in red) seen from the back.
Gray115.png
Anterior surface of sternum and costa cartilages. (False ribs are last five ribs.)
Latin costae spuriae
Gray's subject #28 123

The false ribs are the five sets of ribs below the top seven true ribs. A rib is considered to be "false" if it has no direct attachment to the sternum, also known as the breast bone. Of these:

  • the first three (eighth, ninth, and tenth rib) have their cartilages attached to the cartilage of the rib above (vertebro-chondral):
  • the last two (eleventh rib and twelfth rib) are free at their anterior extremities and are termed floating ribs or vertebral ribs because they connect neither with the sternum nor with another rib.[1] These ribs are relatively small and delicate, and are capped by a cartilaginous tip.[2]

Contents

Ninth rib [edit]

The frontal part of the ninth rib is at the same level as the first lumbar vertebra. This level is called planum transpyloricum, since the pylorus is also at this level.[3]

Tenth rib [edit]

The tenth rib attaches directly to the body of vertebra T10 instead of between vertebrae like the second through ninth ribs. Due to this direct attachment, vertebra T10 has a complete costal facet on its body. In several ethnic groups, most significantly the Japanese, the tenth rib is sometimes a floating rib, as it lacks a cartilaginous connection to the seventh rib.[2]

Additional images [edit]

References [edit]

  1. ^ Ribs. http://www1.american.edu/adonahue/k11ribs.htm. [Web]
  2. ^ a b Saladin, Kenneth (2010). Anatomy and Physiology: The Unity of Form and Function. USA: The McGraw-Hill Companies, Inc. p. 485. ISBN 978-0-07-352569-3. 
  3. ^ Bålens ytanatomi (surface anatomy). Godfried Roomans, Mats Hjortberg and Anca Dragomir. Institution for Anatomy, Uppsala. 2008.

External links [edit]

This article incorporates text from a public domain edition of Gray's Anatomy.