Systematic review of cervical discography as a diagnostic test for chronic spinal pain.

BACKGROUND Chronic neck pain represents a significant public health problem. Despite high prevalence rates, there is a lack of consensus regarding the causes or treatments for this condition. Based on controlled evaluations, the cervical intervertebral discs, facet joints, and atlantoaxial joints have all been implicated as pain generators. Cervical provocation discography, which includes disc stimulation and morphological evaluation, is often used to distinguish a painful disc from other potential sources of pain. Yet in the absence of validation and controlled outcome studies, the procedure remains mired in controversy. STUDY DESIGN A systematic review of the cervical discography literature. OBJECTIVE To evaluate the validity and usefulness of cervical provocation discography in managing and diagnosing discogenic pain by means of a systematic review. METHODS Following a comprehensive search of the literature, selected studies were subjected to a modified Agency for Healthcare Research and Quality (AHRQ) diagnostic accuracy evaluation. Qualitative analysis was conducted using 5 levels of evidence, ranging from Level I to III with 3 subcategories in Level II. The rating scheme was modified to evaluate the diagnostic accuracy. RESULTS A systematic review of the literature demonstrated that cervical discography plays a significant role in selecting surgical candidates and improving outcomes, despite concerns regarding the false-positive rate, lack of standardization, and assorted potential confounding factors. Based on the studies utilizing the International Association for the Study of Pain (IASP) criteria, the data show a prevalence rate ranging between 16% and 20%. Based on the 3 studies that utilized IASP criteria during the performance of cervical discography, the evidence derived from studies evaluating the diagnostic validity of the procedure, the indicated level of evidence is Level II-2 based on modified U.S. Preventive Services Task Force (USPSTF) criteria. LIMITATIONS Limitations include a paucity of literature, poor methodologic quality, and very few studies performed utilizing IASP criteria. CONCLUSION Cervical discography performed according to the IASP criteria may be a useful tool for evaluating chronic cervical pain, without disc herniation or radiculitis. Based on a modified AHRQ accuracy evaluation and USPSTF level of evidence criteria, this systematic review indicates the strength of evidence as Level II-2 for diagnostic accuracy of cervical discography.