Posterior lumbar interbody fusion versus posterolateral fusion with instrumentation in the treatment of low-grade isthmic spondylolisthesis: midterm clinical outcomes

50 patients with low grade lumbar spondylolisthesis were randomized to undergo either posterior lumbar interbody fusion or posterolateral fusion, to compare the safety and efficacy of these treatment methods. Following radiographic and clinical evaluations over an average period of 3.3 years, the results indicated that posterior lumbar interbody fusion provided patients with better clinical scores, higher fusion ratios, and greater improvements in lumbar lordosis and segmental angles than posterolateral fusion.