The grades of recommendations (standards, guidelines, and options) and classes of evidence (I–III) are defined at the end of the "Major Recommendations" field.
Standards. There is insufficient evidence to recommend a treatment standard.
Guidelines. 1) It is recommended that magnetic resonance (MR) imaging be used as a diagnostic test instead of discography for the initial evaluation of patients with chronic low-back pain. 2) It is recommended that MR imaging-documented disc spaces that appear to be normal not be considered for treatment as a source of low-back pain. 3) It is recommended that lumbar discography not be used as a stand-alone test on which treatment decisions are based for patients with low-back pain. 4) If discography is performed as a diagnostic tool to identify the source of a patient's low-back pain, it is recommended that both a concordant pain response and morphological abnormalities be present at the pathological level prior to initiating any treatment directed at that level.
Options. 1) It is recommended that discography be reserved for use in patients with equivocal MR imaging findings, especially at levels adjacent to clearly pathological levels. 2) It is recommended that patients in whom discography is positive but in whom MR imaging evidence of disc degeneration is absent not be considered candidates for operative intervention.
Summary
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 stand-alone test for treatment decisions in patients with low-back pain. MR 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.
Definitions:
Grades of Recommendation
Standards Recommendations of the strongest type, based on Class I evidence reflecting a high degree of clinical certainty
Guidelines Recommendations based on Class II evidence reflecting a moderate degree of clinical certainty
Options Recommendations based on Class III evidence reflecting unclear clinical certainty
Classes of Evidence
Class I Evidence from one or more well-designed, randomized controlled clinical trials, including overviews of such trials
Class II Evidence from one or more well-designed comparative clinical studies, such as nonrandomized cohort studies, case-control studies, and other comparable studies, including less well-designed randomized controlled trials
Class III Evidence from case series, comparative studies with historical controls, case reports, and expert opinion as well as significantly flawed randomized controlled trials