Provocative discography and lumbar fusion: is preoperative assessment of adjacent discs useful?

ABSTRACT

STUDY DESIGN: A cohort study of clinical outcomes of lumbar fusion patients with preoperative assessment of adjacent levels by provocative discography. OBJECTIVE: To evaluate whether the preoperative status of the adjacent discs, as determined by provocative discography, has an impact on the clinical outcome of lumbar fusion in chronic low back pain (LBP) patients. SUMMARY OF BACKGROUND DATA The results of lumbar fusion in chronic LBP patients vary considerably and are hard to predict. It is believed that degenerative levels adjacent to a fused spinal segment may be a cause of continuing pain. In this respect, it is important to know whether preoperative degenerative or symptomatic adjacent levels have an adverse effect on patient outcomes after lumbar fusion. METHODS: In 197 patients with an equivocal indication for lumbar fusion (two thirds were patients with prior spine surgery), the decision for either lumbar fusion or conservative management was determined by a temporary external transpedicular fixation trial. During the diagnostic workup, all patients had undergone provocative discography that included the assessment of the discs adjacent to the intended fusion levels. The individual changes in pain on a visual analog scale, assessed before treatment and at follow-up, and patient satisfaction were the measures of outcome. RESULTS: In the 82 patients who underwent a lumbar fusion, no difference in outcome was found between those patients with degenerative or symptomatic discs adjacent to the fusion and those with normal adjacent discs. CONCLUSION: In this cohort study of chronic LBP patients with an uncertain indication for lumbar fusion, the preoperative status of adjacent levels as assessed by provocative discography did not appear to be related to the clinical outcome after fusion.