Comparison of Instrumented Anterior And Posterior Lumbar Interbody Fusions With Posterolateral Lumbar Fusions Using Pedicle Fixation For Management of Mechanical Back Pain

Methods: 42 patients with mechanical low back pain were treated with lumbar fusion of L4L5 and/or L5S1. Etiologies included recurrent disc herniations, spondylolisthesis, pseudoarthrosis and focal degenerative disease. Parameters included demographics, preoperative studies, operative time, blood loss, levels fused, complications, and outcome. Statistical comparison was performed with ANOVA (p=0.05).

Results: The age and number of levels fused were similar in all three groups. Of 42 patients (14 ALIF, 15 PLIF, 13 PF), spondylolisthesis was more common in PF, whereas litigation/compensation was more common in ALIF. Blood loss was less in ALIF than PLIF (p less than 0.05). Operative time was 30min longer for PF and 50min longer for PLIF than ALIF. Outcome was slightly better with PF then ALIF or PLIF. Two complications were observed in each group. The only two neurological complications occurred with PLIF. Two ALIF patients required structural bone grafts instead of cages because of poor fit.

Conclusions: Although blood loss and operative time were less with ALIF, outcome was slightly better with PF. Spondylolisthesis and litigation/compensation may be related to the observed results. Neurological complications are more likely with PLIF. Most preoperative studies offer limited predictive value of postoperative outcome.