Friday, September 28, 2018 1:00 PM–2:30 PM abstracts: a new look at imaging: 209. Low pressure lumbar provocation discography according to international association for the study of pain or spine intervention society standards does not cause accelerated progression of disc degeneration in symptomatic low back pain patients: a 7-year matched cohort study

Abstract

BACKGROUND CONTEXT Study of subjects without clinically-significant low back pain (LBP) suggests that high-pressure lumbar provocation discography (PD) may cause accelerated disc degeneration. PURPOSE Determine if low-pressure PD, according to IASP/SIS standards,results in accelerated disc degeneration and disruption at long-term follow-up in patients with symptomatic LBP. STUDY DESIGN/SETTING This was a longitudinal matched cohort study conducted in a tertiary, academic spine center. PATIENT SAMPLE Patients with sympatomatic LBP. OUTCOME MEASURES The primary outcome was the proportion of discs that advanced in Pfirrmann score category (I–II, III–IV, and V). MRI T2-signal-intensity-to-CSF ratio, disc height, new disc herniation, new high intensity zones (HIZs), and new Type-1 Modic changes were also assessed. METHODS Consecutive patients with symptomatic LBP who underwent MRI, PD, and repeat MRI>7 years later, but no spinal fusion, were identified by EMR query. Punctured discs were matched at a 1:2-1:4 ratio to corresponding discs in a control cohort by age, BMI, Pfirrmann score (+/−1) and presence of disc herniation; control cohort inclusion required MRIs for symptomatic LBP, separated by >7 years. RESULTS Baseline and follow-up MRIs were available for 66 discs exposed to PD, and 243 discs in the matched cohort. There was no difference in the proportion of punctured discs that advanced in Pfirrmann score category in the PD cohort (17%, 95%CI 9%–28%) compared to the matched cohort (23%, 95%CI 18%–29%), p=0.13, or in punctured (36%, 95%CI 21%–53%) versus nonpunctured (36%, 95%CI 21%–53%) discs within the PD cohort, p=0.97. There were no differences in T2-signal-intensity-to-CSF ratio, disc height, new disc herniations, new HIZs, or new Type-1 Modic changes following puncture in the PD versus matched cohorts or the punctured versus nonpunctured discs within the PD cohort (p's>.05) CONCLUSIONS In patients with symptomatic LBP who underwent provocation discography according to IASP/SIS standards but no subsequent spinal fusion, accelerated progression of disc degeneration or disruption was not observed in comparison to un-punctured discs in a matched cohort or in un-punctured discs within the PD cohort. These results are notable given that PD was in symptomatic patients who were appropriate candidates for this procedure, rather than in patients without clinically-significant LBP who would not undergo PD in realistic clinical practice.