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.
Discography using modern small gauge needle and limited pressure disc injection resulted in accelerated disc degeneration over 10-year follow-up compared to matched controls. New MR findings for disc herniation were disproportionately found on the side of the disc injection compared to the contralateral side. Painful disc injection at baseline did not predict future accelerated disc degeneration.
From the *Stanford University School of Medicine, Stanford, CA; †Department of Public Health Sciences, John A. Burns School of Medicine, University of Hawaii at Mānoa, Honolulu, HI; ‡NYU Hospital for Joint Diseases, New York, NY; §Johns Hopkins University, Baltimore, MD; ¶Hospital for Special Surgery, New York, NY.
Acknowledgment date: November 15, 2008. Acceptance date: January 15, 2009.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Institutional funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Address correspondence and reprint requests to Eugene J. Carragee, MD, Division of Orthopaedic Surgery, Stanford University, 300 Pasteur Drive, Room R171, Stanford, CA 94305; E-mail: firstname.lastname@example.org