Admin Table of Contents
How many individual vertebrae are there of each type?
Vertebrae. Vertebrae are the 33 individual bones that interlock with each other to form the spinal column. The vertebrae are numbered and divided into regions: cervical, thoracic, lumbar, sacrum, and coccyx (Fig. 2).
How many vertebrae pairs are there?
There are 31 pairs of spinal nerves and roots. Eight pairs of cervical nerves exit the cervical cord at each vertebral level. One member of the pair exits on the right side and the other exits on the left. The first cervical root exits above the C1 vertebra.
Why are ribs 11 12 called floating ribs?
The last false ribs (11–12) are also called floating (vertebral) ribs, because these ribs do not attach to the sternum at all. Instead, the ribs and their small costal cartilages terminate within the muscles of the lateral abdominal wall.
How many pairs of floating ribs are in the human body?
There are two pairs of floating ribs and they are the most inferior of the ribs. They are different from the other ribs of the thoracic region because they do not articulate anteriorly with the sternum or the costal cartilage of other ribs. They do articulate with the thoracic vertebrae 11 and 12 posteriorly.
What are the five regions of the vertebral column?
The spine is split into five regions: the cervical, thoracic, lumbar, sacral, and coccyx. The vertebrae of the sacrum and coccyx are fused, but those of the cervical, thoracic, and lumber regions are free to articulate.
How many bones are in the vertebrae?
Vertebrae are the 33 individual bones that interlock with each other to form the spinal column. The vertebrae are numbered and divided into regions: cervical, thoracic, lumbar, sacrum, and coccyx (Fig. 2). Only the top 24 bones are moveable; the vertebrae of the sacrum and coccyx are fused.
How are vertebrae numbered?
Individual vertebrae are numbered from the top down and correspond to the spinal region in which they exist. There are 7 vertebrae in the cervical spine, 12 in the thoracic spine and 5 in the lumbar spine.
How are vertebrates numbered?
The vertebral bodies are numbered from 1 to 5 in the lumbar spine and the discs are located between two of the vertebral bodies and are numbered accordingly (such as a disc at L2-3, or between the lumbar discs numbered 2 and 3).