A Meta-analysis of stand-alone lateral lumbar interbody fusion and lateral lumbar interbody fusion with supplemental posterior instrumentation in the treatment of lumbar degenerative disease

English Keywords:Lateral lumbar interbody fusion  Lumbar degenerative disease  Posterior instrumentation  Fusion rate  Cage subsidence

English Abstract:

  【Abstract】 Objectives: To analyze and compare the outcomes of stand-alone lateral lumbar interbody fusion (LLIF) and LLIF with supplemental posterior instrumentation in the treatment of lumbar degenerative disease by a Meta-analysis. Methods: A comprehensive literature search was performed for comparative studies relevant to stand-alone LLIF(stand-alone group) and LLIF with supplemental posterior instrumentation(instrumented group) in the treatment of lumbar degenerative disease using PubMed, EMBASE, Web of Science, Cochrane Library, CNKI, and Wanfang databases from their establishment to July 2021. The Newcastle-Ottawa scale (NOS) was adopted to evaluate the quality of the included studies. Outcome data was extracted, including fusion rate and cage subsidence rate at the last follow-up; the restoration of disc height, segmental lordosis, and lumbar lordosis at the last follow-up from those before operation; the improvement of visual analogue scale(VAS) score for leg pain and Oswestry disability index(ODI) score at the last follow-up from preoperation; intraoperative blood loss; length of hospital stay; postoperative complication rate, neurologic deficit rate, reoperation rate, and adjacent segment disease development rate. Meta analysis was performed with Review Manager 5.3 software. Continuous outcomes were analyzed by weighted mean difference(WMD), and dichotomous outcomes were analyzed by risk ratio(RR). The 95% confidence interval (CI) of each effect size was provided. Results: A total of 13 high-quality articles comprised of nine cohort studies and four case-control studies were included, involving 1090 patients who underwent LLIF(429 in the stand-alone group and 661 in the instrumented group) for lumbar degenerative disease. The length of follow-up was 17.66±5.39 months and 16.40±5.41 months in the stand-alone group and the instrumented group, respectively. The instrumented group was better than stand-alone group with significant differences in fusion rate(RR 0.92, 95%CI 0.87 to 0.98, P=0.006), cage subsidence rate (RR 1.68, 95%CI 1.36 to 2.07, P<0.00001), the restoration of disc height(WMD -0.68, 95%CI -1.04 to -0.32, P=0.0002) and segmental lordosis(WMD -1.28, 95%CI -2.30 to -0.27, P=0.01), the improvement of ODI(WMD -1.39, 95%CI -2.45 to -0.32, P=0.01), and reoperation rate(RR 2.12, 95%CI 1.02 to 4.43, P=0.04). While, comparing with instrumented group, the stand-alone group had less intraoperative blood loss(WMD -106.62, 95%CI -163.54 to -49.70, P=0.0002). There were no significant differences in the restoration of lumbar lordosis(WMD -1.63, 95%CI -3.36 to 0.10, P=0.06), the improvement of VAS scores(WMD 0.63, 95%CI -0.22 to 1.48, P=0.15), length of hospital stay (WMD-2.37, 95%CI -4.82 to 0.07, P=0.06), complication rate(RR 1.29, 95%CI 0.94 to 1.78, P=0.12), neurologic deficit rate (RR 1.07, 95%CI 0.67 to 1.72, P=0.78), and adjacent segment disease development rate (RR 0.43, 95%CI 0.06 to 3.21, P=0.41). Conclusions: Both stand-alone and instrumented LLIF were effective in improving the clinical outcomes of patients with lumbar degenerative disease. However, the stand-alone LLIF was associated with lower fusion rate, inferior maintenance of indirect decompression, and higher reoperation rate due to high-grade cage subsidence. For patients with risk factors of high-grade cage subsidence, the LLIF with posterior instrumentation may be a better choice.