http://www.thetruthaboutbackpainandphysicaltherapy.org/ The spine is made up of 3 sections and each section has so many vertebrae. If you’re going to talk about back pain then you should know which vertebrae numbers belong to which spine segment. Otherwise, it won’t mean a thing when the doctor tells you that vertebrae T6 is injured. By the way, vertebrae is plural for vertebra. The top section of the spine is called the cervical curve, and it’s composed of vertebrae identified as C1 to C7. The middle of the spine is called the thoracic curve and it’s made of vertebrae identified as T1 to T12. The third section is the lower back, and it’s called the lumbosacral curve. The lumbosacral curve is composed of vertebrae L1 to L5. Below the lower spine is the coccyx or tailbone. The spine is meant to be in balance in order to do its job properly. The spine should be lined up so that the ear, shoulder and hip are in a line. The spine curves, but the body is straight.