Comparison of Anterior Approach and Posterior Approach to Instrumented Interbody Fusion for Spondylolisthesis: A Meta-analysis

OBJECTIVE: To compare outcomes of instrumented interbody fusion by the anterior approach (anterior lumbar interbody fusion [ALIF] with posterior pedicle screw fixation [PPF] or lateral lumbar interbody fusion [XLIF] with PPF) or the posterior approach (transforaminal lumbar interbody fusion [TLIF] or posterior lumbar interbody fusion [PLIF]) for spondylolisthesis through meta-analysis. METHODS: The MEDLINE via PubMed, Cochrane, Scopus, and Embase databases were searched for studies published between January 2010 and January 2019 evaluating outcomes including lumbar lordosis (LL), segmental lordosis (SL), slip rate, disc height (DH), back visual analogue scale (VAS), leg VAS, and Oswestry disability index (ODI) of ALIF with PPF or XLIF with PPF and TLIF or PLIF for spondylolisthesis. Two authors performed the data extraction independently. Any discrepancies were resolved by a consensus. RESULTS: Eight comparative studies were identified. There was no significant difference between the anterior approach and the posterior approach for preoperative LL, SL, and DH. In addition, postoperative back and leg VAS, and ODI between the 2 groups were not different. However, the anterior approach was more effective for restoration of postoperative LL, SL, and DH than the posterior approach. CONCLUSIONS: A literature review identified 8 comparative studies reporting outcomes of the anterior approach and the posterior approach in instrumented interbody fusion for spondylolisthesis. Despite heterogeneity, a limited meta-analysis showed that the postoperative restoration of LL, SL, and DH was better in the anterior approach group. Further large multicenter studies would be necessary to substantiate our results.