Object: The authors compared the effectiveness of instrumented posterior lumbar interbody fusion (iPLIF) and instrumented posterolateral fusion (iPLF) for the treatment of low-back pain (LBP) due to degenerative lumbar disease.
Methods: Relevant randomized controlled trials (RCTs) and comparative observational studies through December 2009 were identified using a retrieval strategy of sensitive and specific searches. The study design, participant characteristics, interventions, follow-up rate and period, and outcomes were abstracted after the assessment of methodological quality of the trials. Analyses were performed following the method guidelines of the Cochrane Back Review Group.
Results: Nine studies were identified-3 RCTs and 6 comparative observational studies. No significant difference was found between the 2 fusion procedures in the global assessment of clinical outcome (OR 1.51, 95% CI 0.71-3.22, p = 0.29) and complication rate (OR 0.55, 95% CI 0.16-1.86, p = 0.34). Both techniques were effective in reducing pain and improving functional disability, as well as restoring intervertebral disc height. Instrumented PLIF was more effective in achieving solid fusion (OR 2.60, 95% CI 1.35-5.00, p = 0.004), a lower reoperation rate (OR 0.20, 95% CI 0.03-1.29, p = 0.09), and better restoration of segmental angle and lumbar lordotic angle than iPLF. There were no significant differences between the fusion methods regarding blood loss (weighted mean difference -179.63, 95% CI -516.42 to 157.15, p = 0.30), and operating time (weighted mean difference 8.03, 95% CI -45.46 to 61.53, p = 0.77).
Conclusions: The authors' analysis provided moderate-quality evidence that iPLIF has the advantages of higher fusion rate and better restoration of spinal alignment over iPLF. No significant differences were identified between iPLIF and iPLF concerning clinical outcome, complication rate, operating time, and blood loss.