Comparison of posterolateral lumbar fusion and posterior lumbar interbody fusion for patients younger than 60 years with isthmic spondylolisthesis.

Abstract

Prospective randomized study. To determine whether single-level posterolateral lumbar fusion (PLF) or posterior lumbar interbody fusion (PLIF) was associated with better outcomes for patients 60 years or younger with isthmic spondylolisthesis. Although both PLF and PLIF are considered effective surgical treatments for isthmic spondylolisthesis, it is unknown which treatment leads to better outcomes. In addition, previous studies of the therapeutic efficacy of PLIF and PLF had several weaknesses, so they could not provide clear data on the therapeutic outcomes of each treatment. Of the 85 patients screened for this study, 4 did not meet the study criteria. Thus, 81 patients were enrolled and randomly assigned into group A (PLF, n = 39) or group B (PLIF, n = 42). The primary outcome measure was the fusion rate based on dynamic radiographs and computed tomographic scans at postoperative 1 and 2 years. The secondary outcome measures were (1) clinical outcomes as assessed with a visual analogue scale and the Oswestry Disability Index, (2) surgical outcomes, and (3) additional outcomes such as infection and metal failure. No patients were lost to follow-up. The fusion rate was similar between groups: fusion occurred in 84.6% (33/39) in group A and 85.7% (36/42) in group B at 1 year after surgery (P = 0.86), and 89.7% (35/39) in group A and 90.4% (38/42) in group B at 2 years after surgery (P = 0.93). Postoperative pain levels and functional outcomes did not differ significantly between groups at any of the regular follow-up visits. The prevalence of complications also did not differ significantly between groups; the only serious complication (deep infection) occurred in 1 patient in the PLIF group. Both PLF and PLIF are viable surgical options for patients with isthmic spondylolisthesis 60 years or younger.