Where the axis (c2) sits in the skeleton
The axis is the second cervical vertebra (C2). The atlas turns around its upward peg, the dens, which is where the head turns side to side. The dens rises from its body and sits behind the anterior arch of the atlas, forming a pivot joint. Its spinous process is large with a split tip, and it is the first spinous process you can feel below the back of the skull.
Frequently asked questions
Which part of the skeleton is the axis in?
The axis is one of the bones of the vertebral column. Seven cervical, twelve thoracic and five lumbar vertebrae and the sacrum are stacked to support the trunk and enclose the spinal cord.
How many vertebrae are there?
The spine has 24 separate vertebrae. From the top there are seven cervical (neck), twelve thoracic (upper back) and five lumbar (lower back) vertebrae, followed by the sacrum and the coccyx.
Which bones are above and below the axis?
Above the axis is the atlas (C1), and below it is the third cervical vertebra (C3).
What is the dens?
A tooth-shaped peg rising from the body of the axis. It sits behind the anterior arch of the atlas, held there by the transverse ligament, and the atlas turns around it.
Other bones of the vertebral column
- Atlas (C1)
- Third cervical vertebra (C3)
- Fourth cervical vertebra (C4)
- Fifth cervical vertebra (C5)
- Sixth cervical vertebra (C6)
- Seventh cervical vertebra (C7)
- First thoracic vertebra (T1)
- Second thoracic vertebra (T2)
- Third thoracic vertebra (T3)
- Fourth thoracic vertebra (T4)
- Fifth thoracic vertebra (T5)
- Sixth thoracic vertebra (T6)
- Seventh thoracic vertebra (T7)
- Eighth thoracic vertebra (T8)
- Ninth thoracic vertebra (T9)
- Tenth thoracic vertebra (T10)
- Eleventh thoracic vertebra (T11)
- Twelfth thoracic vertebra (T12)
- First lumbar vertebra (L1)
- Second lumbar vertebra (L2)
- Third lumbar vertebra (L3)
- Fourth lumbar vertebra (L4)
- Fifth lumbar vertebra (L5)
- Sacrum
Joints of the axis
Compare with similar bones
Bone counts
By region
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