Does discography damage the discs?

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A few days ago Crystal posted an abstract by Dr. Carragee (below) about the risk of damaging the disc with discography. Thank you Crystal! This is a great subject that deserves its own thread. I'm sure this will be a great discussion.

The question, “does discography damage a healthy disc” is something that’s been discussed on the forums for years. The abstract that Crystal posted below really piqued my interest. I’ve discussed this extensively with dozens of leading surgeons and pain management doctors over the years. Many will say that poking a small gauged needle through the “radial ply” fibers of the annulus is much like poking a knitting needle through a knit wool sweater. That would do no discernible damage, whereas, poking a pin through a silk blouse will ruin it. Some doctors are discography naysayers. I think that's more about the results controversy than the damage to the disc. Early discography techniques that were fraught with errors. I think much of the bad rap is dogma associated with the old horror stories.

Discography done on a degenerated disc may be another story. Some of the doctors will still say it’s harmless, while others will concede that in a severely degenerated disc discography may push it over the edge. This would not necessarily be from the damage to the annulus. IMHO, this is more likely from an existing protrusion that would be exacerbated by pressurizing the disc, lubricating and increasing the nucleus volume. My second discography was only at L5-S1 to rule it out. We were hoping that I was a single level candidate. I could have been one of the first US Charite’ patients. About three weeks after the discography my left foot went numb. Until that point, I had no radiculopathy associated with my L5-S1 disc. While there was a substantial bulge, there was no frank protrusion at the time of the discography. Remarkably, an MRI a few weeks later showed a new, large (15mm) protrusion at L5-S1. While nobody could say what happened, I do believe that the discography substantially increased the risk of, or may have actually caused the protrusion.

For years, when my clients had asked me about doing discography that was recommended by their surgeons, I have usually suggested that they should only do the discography if they are prepared to follow through with treatment if the discography is positive. With their risk of discography making a very bad disc and worse I believe that it's a mistake to have discography unless you have been through the decision making process and field that your situation justifies having surgery if the discography is positive. There is no such thing as risk free access anywhere in the spine. Control levels have been thought of as important, but the idea of poking and needle into a healthy disc makes me wonder.

I believe that discography is still an important and useful tool that increases the probability of a correct diagnosis. However, it is not the be all, end all definitive test. It’s just another useful tool. Technique is important. A poorly done discography can cloud the situation. Under the best of circumstances, there may still be a risk of false positive or false negative results. If I need to rule levels in or out, all still have discography. This is a very interesting study. I look forward to seeing where this goes as the science improves.

Let the discussion begin!

Mark

Originally Posted by Crystal33

2009: Carragee Eugene J; Don Angus S; Hurwitz Eric L; Cuellar Jason M; Carrino John; Herzog Richard

2009 ISSLS Prize Winner: Does discography cause accelerated progression of degeneration changes in the lumbar disc: a ten-year matched cohort study.
Spine 2009;34(21):2338-45.

STUDY DESIGN: Prospective, match-cohort study of disc degeneration progression over 10 years with and without baseline discography. Objectives. To compare progression of common degenerative findings between lumbar discs injected 10 years earlier with those same disc levels in matched subjects not exposed to discography. Summary of Background Data. Experimental disc puncture in animal and in vivo studies have demonstrated accelerated disc degeneration. Whether intradiscal diagnostic or treatment procedures used in clinical practice causes any damage to the punctured discs over time is currently unknown.

METHODS: Seventy-five subjects without serious low back pain illness underwent a protocol MRI and an L3/4, L4/5, and L5/S1 discography examination in 1997. A matched group was enrolled at the same time and underwent the same protocol MRI examination. Subjects were followed for 10 years. At 7 to 10 years after baseline assessment, eligible discography and controlled subjects underwent another protocol MRI examination. MRI graders, blind to group designation, scored both groups for qualitative findings (Pfirrmann grade, herniations, endplate changes, and high intensity zone). Loss of disc height and loss of disc signal were measured by quantitative methods.

RESULTS: Well matched cohorts, including 50 discography subjects and 52 control subjects, were contacted and met eligibility criteria for follow-up evaluation. In all graded or measured parameters, discs that had been exposed to puncture and injection had greater progression of degenerative findings compared to control (noninjected) discs: progression of disc degeneration, 54 discs (35%) in the discography group compared to 21 (14%) in the control group (P = 0.03); 55 new disc herniations in the discography group compared to 22 in the control group (P = 0.0003). New disc herniations were disproportionately found on the side of the anular puncture (P = 0.0006). The quantitative measures of disc height and disc signal also showed significantly greater loss of disc height (P = 0.05) and signal intensity (P = 0.001) in the discography disc compared to the control disc.

CONCLUSION: Modern discography techniques using small gauge needle and limited pressurization resulted in accelerated disc degeneration, disc herniation, loss of disc height and signal and the development of reactive endplate changes compared to match-controls. Careful consideration of risk and benefit should be used in recommending procedures involving disc injection.