Discography (Discogram)

How does it work?
Discography can be performed for the lumbar, thoracic and cervical disks. Most frequently the lower lumbar disks are the target.

This is a purely DIAGNOSTIC procedure which involves injecting contrast material into the most inner aspect of each intervertebral disc (nucleus).This will provide direct information about nuclear morphology, inside pressure and integrity of the vertebral endplates and annulus. The resulting changes in the volume and pressure produce direct stimulation of the disc. At the time of the procedure the patient is rating the discomfort and pain induced by the injection into the disc and this is corroborated with the objective measures recorded during the intervention. For instance, the above picture shows an abnormal middle disc with leakage of the dye outside the disc structure, while the discs below and above are normal.

A diagnosis of internal disc disruption can be made via discography. This condition is fundamentally different from symptomatic disc herniation, when nerve compression by a disc produces leg pain as the dominant complaint. MRI is a powerful tool in detecting disc abnormalities. It can be however an extremely non sensitive test, since patients can have abnormal discs on MRI without concomitant pain in that area, and vice versa.

The discogram complements the MRI studies for the purpose of diagnosis of those disc pathologies that can be amenable to treatment. Such treatments include IDET and instrumental spinal fusion. Discography remains the most accurate method of establishing annular competence. Patients who are severely depressed, have active infections or have a very low threshold for pain are not ideal candidates for this procedure.

Discography is planned only for patients who have exhausted other conservative measures and continue to display unrelenting chronic pain. Possible side effects should be judiciously balanced against the potential benefits.

Discograms in the thoracic and cervical area can be performed as well, while the procedure itself can be more challenging. Again, each patient should be individually assessed and all the benefits, risks and alternatives should be clearly understood.

What to expect during the procedure?
The patient is placed in a face down position for the lumbar and thoracic discogram, while for the cervical discogram a face up position is chosen.

The appropriate area is prepped with an antiseptic solution and a local anesthetic is used to numb the skin. A light sedative is usually administered, but the patient remains awake during the procedure. It is imperative that the true level of pain is clearly assessed during the provocation testing, therefore no opioid analgesics are given prior to this procedure. When the needle penetrates the outer aspect of the annulus, a vague, diffuse cramp- like discomfort is perceived in the back area. This is short lasting. After the needle(s) are placed in the involved disc(s), each needle is pressurized and the level of pain is closely monitored, while each pressure is separately recorded. At the end of the procedure, before the needles are removed a small amount of antibiotic medication is injected into the disc. This has been shown to significantly decrease the chance of disc infection (discitis) after the procedure, a very rare event which can occur in 0.3 - 0.5 % of all cases.

Some transient discomfort may persist for a few days after the procedure, which generally responds very well to anti inflammatory medication and light analgesics.