Discography.

Discography is a purely diagnostic interventional procedure performed to confirm or refute the hypothesis that a specific lumbar disc is the predominant source of a patient's low back pain. In patients with severe low back pain, unresponsive to conservative care, discography is used when clinical evaluation suggests that the pain is emanating from the intervertebral disc and other sources of pain have been ruled out. The evidence for its use remains controversial. There is variability and subjectivity in discography techniques and diagnostic criteria, making some investigators question its validity. When standardized diagnostic criteria are used, however, the specificity of discography improves dramatically. Recently long-term side effects have been studied, and lumbar discography seems to increase disc degeneration and herniation as detected on magnetic resonance imaging. Although the clinical significance is unclear, it is an important risk to consider prior to performing discography, and changes in discography techniques may be indicated. Discography remains the only technique, however, that can be used to determine whether a patient's low back pain is emanating from the intervertebral disc and is a valid test when coupled with careful patient selection, strict adherence to standardized technique and diagnostic criteria, and consideration of possible long-term sequelae.