Which vertebra is known as the Atlas?

The Atlas refers to the first cervical vertebra, which is crucial for supporting the skull and enabling the nodding motion of the head—like the position of the mythical figure Atlas who holds up the world. This vertebra has a unique structure that allows it to articulate with the occipital bone of the skull, facilitating a crucial connection between the brain and spinal column. The Atlas is designed to rotate and tilt, providing a wide range of motion essential for head movements.

The second cervical vertebra, known as the Axis, plays a complementary role by allowing rotation of the head, particularly in combination with the Atlas. The last cervical vertebra, referred to as C7 or the vertebra prominens, does not have the unique functionality associated with the Atlas. Thoracic vertebrae, located in the mid-back, have an entirely different function related to the rib cage and do not participate directly in the same movements as the cervical vertebrae. Thus, the first cervical vertebra's distinctive role in the flexibility and support of the head signifies why it is termed the Atlas.