Circumferential Fusion Improves Long-Term Outcome In Comparison To Instrumented Posterolateral Fusion. A Randomized Clinical Study with 5-9 Years Follow-Up

Introduction: Although lumbar spine fusion is a common used treatment in low back pain, controversy still exists on the choice of surgical technique. Circumferential fusion has become a common surgical procedure. However, the long-term claimed advantages of anterior lumbar interbody fusion (ALIF) plus posterolateral lumbar fusion (PLF) over conventional PLF lack scientific documentation. Aim: To analyze the effects of circumferential fusion on long-term outcome with respect to functional disability, pain and general health.

Methods: From April 1996 through November 1999 a total of 148 patients with severe chronic low back pain were randomly selected for either posterolateral lumbar fusion or circumferential fusion (ALIF plus PLF). The primary outcome measure was the Dallas Pain Questionnaire (DPQ). The secondary outcome measures were the Oswestry Disability Index, the SF-36 instrument and the Low Back Pain Rating Scale. All measures assessed the end-point outcomes at 5-9-years postoperatively.

Results: The available response rate was 93%. The circumferential group showed a significantly better improvement (p<0 .05) in comparison to the posterolateral group with respect all four DPQ categories: daily activities, work/leisure, anxiety/depression and social interest. The Oswestry Disability Index SF-36 (physical health category) supported these results (p<0.01). circumferential experienced significantly less back pain (p<0.05) group.

Discussion: Circumferential lumbar fusion demands more extensive operative resources compared to posterolateral lumbar fusion. However, 5-9 years after surgery the circumferentially fused patients had a significantly improved outcome compared to those treated by means of PLF. These new results emphasize the superiority of circumferential fusion in the complex pathology of the lumbar spine, and are strongly supported in all of the validated questionnaires employed in the study.