Additional testing is required to assign a "pain generator" status to the individual disc. Discography is accepted as the disc evaluation "procedure-of-choice". Discography investigates, and establishes the intervertebral discs role in the production of the patient's low back pain.At times in the past the value of discography has been questioned. Current literature supports discography's worth as a diagnostic tool used to investigate painful spinal conditions.

DISCOGRAPHY CANDIDATES

A patient who experiences persistent spinal (cervical, thoracic, lumbar) pain

A disc abnormality is suspected

Non-invasive tests have failed to provide an explanation or source of pain

A pain correlation is desired

Patients who have continued pain despite previous surgery are often discography candidates. There are many variations of the discography procedure. The method most commonly utilized at Heartland Hand and Spine is that of provocative discography. Provocative discography is the instillation of sterile saline (not dye) into the disc looking for reproduction of the patient's pain. Exact pain reduction supports the discs role as a "pain generator", documenting a specific diagnosis, and allows more aggressive intervention. 

HISTORY OF DISCOGRAPHY

Discography was originally performed with dye, when existing imaging techniques did not provide information on the disc's internal architecture. In most present cases we utilize the MRI to identify disc abnormalities and the discogram to assign a "pain generator" status.

Historically, Lindblom (1940's) injected cadaveric specimens with red lead containing dyes and examined the pattern of distribution within the disc. Erlacher (1952), studied 200 cadaver disc specimens and found that discography accurately represented the disc anatomy. The discs were sectioned and studied for correlation. Wiley (1968) reported on 1092 patients, finding discography a valuable tool with very few complications. In one study of the MRI, significant disc abnormalities were demonstrated in 28% of symptom and pain-free individuals (28% false-positive rate). Clearly a procedure is needed to further define the MRI findings as contributing to the patient's symptoms. Discography is the only method that directly relates a radiographic image to the patient's pain.

Walsh et al (1990), performed provocative discography on ten asymptomatic pain-free volunteers. No pain was produced on injection. However, 50% demonstrated abnormal dye patterns. He felt the pain correlation the procedure had a specificity of 100%. Simmon's et al's (1990), suggested that treating painful spinal conditions based only on MRI results could lead to under treatment.

Colhoun et al (1988), studied the success of fusions performed with a discography proven pain correlation. Patient satisfaction was achieved in 88%. When the correlation was absent the satisfaction with the fusion procedure dropped to 52%. Discography has also been documented as helpful in diagnosing pseudarthrosis (failure-of-fusion), Byrd (1992).

• Failed conservative therapy

• Diagnostic tests - inconclusive (equivocal or inconsistent)

• Persistence of severe symptoms - surgery a consideration