Guidelines for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 6: magnetic resonance imaging and discography for patient selection for lumbar fusion.

Discography is an exquisitely sensitive but not specific diagnostic test for the diagnosis of discogenic low-back pain. The restriction of the definition of a positive discographic study to one that elicits concordant pain from a morphologically abnormal disc improves the definition's accuracy. Fusion surgery based on discography alone, however, is not reliably associated with clinical success. Therefore, discography is not recommended as a standalone test for treatment decisions in patients with low-back pain. Magnetic resonance imaging is a sensitive and noninvasive test for the presence of degenerative disc disease. Discography should not be attempted in patients with normal lumbar MR images. Discography appears to have a role in the evaluation of patients with low-back pain, but it is best limited to the evaluation of abnormal interspaces identified on MR imaging, the investigation of adjacent-level disc disease, and as a means to rule out cases of nonorganic pain from surgical consideration.