Question

Vertebrochondral ribs in man are
(a) ${ 8 }^{ th }$,${ 9 }^{ th }$,${ 10 }^{ th }$
(b) ${ 7 }^{ th }$,${ 8 }^{ th }$,${ 9 }^{ th }$
(c) ${ 9 }^{ th }$,${ 10 }^{ th }$,${ 11 }^{ th }$
(d) ${ 6 }^{ th }$,${ 7 }^{ th }$,${ 8 }^{ th }$

Answer 1

Hint: It has a frontal part at the same level as the first lumbar vertebra. This level is named the transpyloric plane since the pylorus is additionally at this level. It attaches directly to the body of the vertebra instead of between the vertebrae. Due to this direct attachment, the vertebra has a complete costal facet on its body.

Complete step by step answer:
In our body 33 ribs are present. Every rib is thin and flat in structure and the bone is connected dorsally to the vertebral column and ventrally to the sternum. On its dorsal end, it can contain two articulation surfaces and so it is called bicephalic.
There are seven pairs of ribs known as true ribs. Dorsally, they're joined to the thoracic vertebrae and ventrally associated with the sternum with the help of ligament. And the eighth-to-twelfth pair of ribs are called Vertebrochondral ribs. The ${ 8 }^{ th }$ to ${ 10 }^{ th }$ pairs of ribs connect to the sternum indirectly with the help of the costal cartilages of the ribs above them.

Additional information
There are three pairs of false ribs. They are intermediate between truth ribs and therefore the floating ribs. They are sometimes called vertebrochondral ribs. It is different from the true ribs because they do not directly articulate with the sternum. Their costal cartilages join together, however. Many authors include the floating ribs during this group, thereby making five pairs of false ribs.

So the correct answer to the above question is ‘${ 8 }^{ th }$,${ 9 }^{ th }$,${ 10 }^{ th }$’.

Note:
There are two sets of floating ribs and they are the most second rate of the ribs. They are different from the opposite ribs of the thoracic region because they are not articulated anteriorly with the sternum or the cartilaginous structure of other ribs. The thoracic vertebrae 11 and 12 posteriorly and do articulate. They do have a cartilaginous structure that's embedded within the muscles of the body wall up the lateral region. They are sometimes called vertebral ribs.