A systematic review with meta-analysis of posterior interbody fusion versus posterolateral fusion in lumbar spondylolisthesis

Abstract

Purpose: To compare the clinical effectiveness of posterior lumbar interbody fusion (PLIF) and posterolateral fusion (PLF) for lumbar spondylolisthesis and to collect scientific evidence for determining which fusion method is better.

Methods: After systematic search, comparative studies were selected according to eligibility criteria. Checklists by Furlan and by Cowley were used to evaluate the risk of bias of the included randomized controlled trials (RCTs) and nonrandomized controlled studies, respectively. Weighed mean differences (WMDs) and risk differences were calculated for common outcomes. The final strength of evidence was expressed as different levels recommended by the GRADE Working Group.

Results: Four RCTs and five comparative observational studies were identified. Moderate-quality evidence indicated that PLIF was more effective than PLF for clinical satisfaction [odds ratios (OR) 0.49, 95 % confidence limits (95 % CI): (0.28, 0.88, P = 0.02)]. Moderate-quality evidence showed that no significant difference was found for the complication rate [OR 2.28, 95 % CI (0.97, 5.35), P = 0.06]. In secondary outcomes, moderate-quality evidence indicated that PLIF improved fusion rate [OR 0.32, 95 % CI (0.17, 0.61), P = 0.0006]. Low-quality evidence showed that PLIF resulted in a lower reoperation rate than PLF [OR 5.30, 95 % CI (1.47, 19.11), P = 0.01]. No statistical difference was found between the two groups with regard to blood loss [WMD = 76.52, 95 % CI (-310.68, 463.73), P = 0.70] and operating time [WMD = -1.20, 95 % CI (-40.36, 37.97), P = 0.95].

Conclusions: Moderate-quality evidence indicates that PLIF can improve the clinical satisfaction and increase the fusion rate compared to PLF. No superiority was found between the two fusion methods in terms of complication rate, amount of blood loss, and operating time for the treatment of lumbar spondylolisthesis.

Fig. 1

Flowchart of the study selection process

Fig. 2

Clinical satisfaction of PLF versus PLIF for the treatment of lumbar spondylolisthesis. The assessment of clinical satisfaction was based on the scores of ODI and the Prolo Economic and Functional scale and the objective evaluation from patients. Significant difference was observed for overall effect, favoring PLIF with higher clinical satisfaction. Subgroup analysis showed inconsistent results between RCTs and observational studies

Fig. 3

Postoperative back pain of PLF versus PLIF for the treatment of lumbar spondylolisthesis. Both overall and subgroup analyses showed statistical differences between the two procedures. Relief of back pain was more significant in the PLIF group compared to the PLF group

Fig. 4

Complication rate of PLF versus PLIF for the treatment of lumbar spondylolisthesis. No significant difference was found for the complication rate between the two fusion procedures. I ² was >50 %, indicating substantial heterogeneity in the RCTs

Fig. 5

Fusion rate of PLF versus PLIF for the treatment of lumbar spondylolisthesis. The fusion rate in the PLIF group was lower than that in the PLF group

Fig. 6

Reoperation rate of PLF versus PLIF for the treatment of lumbar spondylolisthesis. Lower reoperation rate in the PLIF group was observed in this forest plot

Fig. 7

Blood loss of PLF versus PLIF for the treatment of lumbar spondylolisthesis. No significant difference was found between the two groups. The I ² was >75 %, indicating considerable heterogeneity in the included studies

Fig. 8

Operating time of PLF versus PLIF for the treatment of lumbar spondylolisthesis. No significant difference was found for operating time between the two groups. Inconsistency was obvious in the included studies