An Update of the Systematic Appraisal of theAccuracy and Utility of Discography in ChronicSpinal Pain

BACKGROUND: The intervertebral disc has been implicated as a major cause of chronic spinal pain based on clinical, basic science, and epidemiological research. There is, however, a lack of consensus regarding the diagnosis and treatment of intervertebral disc disorders. Based on controlled evaluations, lumbar intervertebral discs have been shown to be the source of chronic back pain without disc herniation in 26% to 39% of patients, and in 16% to 53% of patients with pain in the cervical spine. Lumbar, cervical, and thoracic provocation discography, which includes disc stimulation and morphological evaluation, is often used to distinguish a painful disc from other potential sources of pain. Despite the extensive literature on point, intense debate continues about lumbar discography as a diagnostic tool. STUDY DESIGN: A systematic review of the diagnostic accuracy of lumbar, cervical, and thoracic provocation and analgesic discography literature. OBJECTIVE: To systematically assess and re-evaluate the diagnostic accuracy of lumbar, cervical, and thoracic discography. METHODS: The available literature on discography was reviewed. A methodological quality assessment of included studies was performed using the Quality Appraisal of Reliability Studies (QAREL) checklist. Only diagnostic accuracy studies meeting at least 50% of the designated inclusion criteria were included in the analysis. To assess the level of evidence, a modified grading of qualitative evidence criteria was utilized, with grading of evidence into 5 categories from Level I to Level V incorporating evidence obtained from multiple high quality diagnostic accuracy studies for Level I and opinion or consensus of a large group of clinicians and/or scientists for Level V. Data sources included relevant literature identified through searches of PubMed and EMBASE from 1966 to June 2017, and manual searches of the bibliographies of known primary and review articles. RESULTS: Over 100 manuscripts were considered for inclusion. Of these, 8 studies met inclusion criteria for diagnostic accuracy and prevalence with 5 studies assessing lumbar provocation discography and 3 studies assessing cervical discography. The results showed variable prevalence from 16.9% to 26% for discogenic pain and 16.9% to 42% for internal disc disruption. The cervical discogenic pain prevalence ranged from 16% to 53%. Based on methodological quality assessment criteria the strength of evidence for lumbar provocation discography is Level III and for cervical discogenic pain is Level IV. LIMITATIONS: Despite multiple publications in the lumbar spine, value and validity of discography continues to be debated. In reference to cervical and thoracic discography, the available literature and value and validity continues to be low. CONCLUSION: This systematic review illustrates that lumbar provocation discography performed according to the International Association for the Study of Pain (IASP) criteria may be a useful tool for evaluating chronic lumbar discogenic pain. The evidence is weaker for cervical and nonexistent for thoracic discography. KEY WORDS: Lumbar intervertebral disc, cervical intervertebral disc, thoracic intervertebral disc, discography, provocation discography, analgesic discography, diagnostic accuracy, prevalence.