C1 through C7
C1 through C7 refers to the seven (C1, C2, C3, C4, C6, C6,
C7) vertebrae (bones that form an opening in which the
spinal cord passes) that are in the neck. The letter "C"
stands for "cervix," which is Greek for "neck." C1 refers to
the 1st cervical bone, C2 to the 2nd cervical bone, C3 to
the 3rd cervical bone, and so on, until C7, which is the last
cervical bone.

C1 is at the top and C7 is at the bottom, with the numbers in
between going down the body in numerical order. For
example, C3 is below C2, C4 is below C3, and so on.

FEATURED BOOK: Fixing You: Neck Pain & Headaches
C1 through C7
These numeric levels are often mentioned on imaging studies of the spine such as
computerzed axial tomography (CT) scans or magnetic resonance imaging (MRI). CT
scanning is an advanced imaging technique that uses x-rays and computer technology to
produces clear and detailed picture of the body area being examined. MRI scans
produce extremely detailed pictures of the inside of the body by using very powerful
magnets and computer technology.

Other designations for other levels of the vertebrae include a) T1 through T12, where T
stands for the thorax (chest) area; b) L1 through L5, where L stands for the lumbar
(lower back) area, and c) S1 through S5, where S stands for the sacral (sacrum) area.
The cervical vertebrae are located above the thoracic vertebrae.
"Where Medical Information is Easy to Understand"™