Provocative Discography: Diagnostic Efficacy and Safety in Symptomatic Degenerative Disk Disease.

Abstract

This was a retrospective cohort analysis. The objective of this study was to report the efficacy and safety profile of provocative discography. It is reported that the provocative discogram as a diagnostic test for symptomatic degenerative disk disease induces disk degeneration. Discogram cases from 1998 to 2011 were identified. A matched control group with no discogram was identified. Both had pre-magnetic resonance imaging (MRI) and post-MRI with 5 years minimum between MRI studies. Statistics were generated by group for each level and for all levels combined. The discogram cohort comprised 53 patients (193 disks). The control group had 51 subjects (255 disks). There were no significant demographic differences between the groups. Time intervals between the index and follow-up MRI were 11 and 8 years for the discogram and control groups, respectively. The most common injected level was L4-L5; the most painful level was L5-S1 (Visual Analog Scale=7.9); the most concordant level was L5-S1 (75%). The most deranged level as seen on discography was L5-S1 (98%). Degeneration from normal to abnormal MRI among discogram patients was 60%. For controls, the rate was 33%. The discogram and control cohorts were statistically different (P<0.01). Among discogram patients, 58% had a fusion surgery between MRI studies. Comparing the discogram group without interval fusion to controls, the degeneration rate was not different at a 5 years' minimum follow-up. The L5-S1 intervertebral disk level was the most painful, concordant, and deranged level as seen on discogram. Patients who underwent a provocative discogram and interval fusion had a higher rate of subsequent degeneration than similar low back pain sufferers with no discogram. Degeneration rates were comparable at 5 years' minimum follow-up between discogram patients without interval spine fusion and patients without discogram exposure. The provocative discogram did not accelerate degeneration among these patients.