Why are there eight cervical nerve roots?

Answer 1

There are 8 cervical nerves because the first 7 nerves exits on the upper part of the vertebrae making up 7 nerves but then on the 7th vertebrae there's another nerve that exits below the vertebrae thus making up 8 cervical nerves from 7 cervical vertebrae.

Answer 2

There are 8 cervical spinal nerves and only 7 cervical vertebral bodies because during embryonic development, one the the somites splits to become part of the occipital bone and the dens of the C2 vertebrae. Thus, the spinal nerve associated with that somite lies above C1 and the rest of the vertebrae are renamed accordingly.

Answer 3

That's because the first cervical nerve falls right between the occipital condyles of the occipital bone of the skull and the first cervical vertebrae. So from bone nerve to bone to nerve it goes like this: Skull, CN 1, C1, CN2, C2, CN3, C3, CN4, C4, CN5, C5, CN6, C6, CN7, C7, CN8, T1... It's like if you line up a bunch of red and blue M&Ms, and the red M&Ms are cervical nerves, the blue M&Ms are vertebrae, put a green one at the top to signify the skull, and a yellow one at the bottom to represent the thoracic vertebrae #1, then lay them all out. You'll have green, red 1, blue 1, red 2, blue 2, red 3, blue 3, red 4, blue 4, red 5, blue 5, red 6, blue 6, red 7, blue 7, red 8, and then yellow.