A discogram is an X-ray examination of the inter-vertebral discs. This test is used to determine which disc(s) are damaged and if those discs are causing pain. This test will show if a disc has begun to rupture and will show if the disc has tears in the tough outer ring called the “annulus”. Usually the test is done after an MRI if the MRI fails to show a herniated disc.
The discogram is performed by placing a needle through the skin along the center of the back into the center of the disc space. A special dye is injected into the disc that will enable the physician to view the disc in detail. Regular X-rays of the spine only give a clear picture of bones, such as the vertebrae. Myelograms only give a clear picture of the spinal canal. Discograms, however, enable the physician to view the disc itself. The special dye used in the procedure shows up white on X-rays which in turn helps the physician in an accurate diagnosis. The results of a discogram may confirm the necessity for surgery, as well as determine the exact cause of a person’s back pain, which will increase the likelihood of a positive outcome from surgery.