The lifetime prevalence of low back pain is approximately 80%. One of the most common causes of back pain is degenerative disc disease. Normal healthy discs are made of a tougher outer cover, the annulus fibrosis, and a softer center, the nucleus pulposis. One of the purposes of discs is to act as shock absorbers between the adjoining vertebral bodies through which body weight is transmitted.

As aging progresses, normal discs begin to dry and narrow. The degenerated disc can weaken allowing the annulus to tear and fray. A degenerated disc may cause pain by itself from irritation of nerves which supply the outer parts of the annulus fibrosis. Additionally, degenerative changes can lead to disc bulges, protrusions and herniations. In turn, these abnormalities may cause nerve compression, spinal stenosis, or spinal instability and will also cause osteoarthritis of the other supporting structures of the spine, the facet joints.

Degenerative disc disease is a very common process and usually affects more than one level in the spine. Such findings can be seen on CT, myelography and even better on MRI. The confusing matter is that not all degenerative discs cause pain, making surgical planning difficult. This is where discography becomes important.

The procedure is done on an outpatient basis and is very simple, having a very low complication rate. The test takes about an hour and the patient is routinely observed afterwards for approximately one hour before going home.

The procedure involves sterilely placing a small needle in a disc space while the patient lies on their stomach. X-ray guidance is utilized to confirm placement and to avoid nearby nerves and vessels. Once in position, contrast dye is injected to visualize any degenerative changes of the disc. More importantly, however, is to monitor any elicited pain during the injection. Symptomatic degenerative discs will recreate patient symptomatology once injected. This pain may immediately be relieved with local anesthesia administration. After the injection, the patient is brought to the CT scanner for additional high resolution images to look for additional degenerative changes.

Overall, discography helps surgeons plan their operations knowing which discs to treat specifically so as to minimize their interventions, but yet come to a cure for back pain.