Minimally Invasive Surgery Versus Open Surgery Spinal Fusion for Spondylolisthesis: A Systematic Review and Meta-analysis

Study Design.Systematic review and meta-analysis.Objective.Compare minimally invasive surgery (MIS) and open surgery (OS) spinal fusion outcomes for the treatment of spondylolisthesis.Summary of Background Data.OS spinal fusion is an interventional option for patients with spinal disease who have failed conservative therapy. During the past decade, MIS approaches have increasingly been used, with potential benefits of reduced surgical trauma, postoperative pain, and length of hospital stay. However, current literature consists of single-center, low-quality studies with no review of approaches specific to spondylolisthesis only.Methods.This first systematic review of the literature regarding MIS and OS spinal fusion for spondylolisthesis treatment was performed using the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines for article identification, screening, eligibility, and inclusion. Electronic literature search of Medline/PubMed, Cochrane, EMBASE, and Scopus databases yielded 2489 articles. These articles were screened against established criteria for inclusion into this study.Results.A total of five retrospective and five prospective articles with a total of 602 patients were found. Reported spondylolisthesis grades were I and II only. Overall, MIS was associated with less intraoperative blood loss (mean difference [MD], -331.04mL; 95% confidence interval [CI], -490.48 to -171.59; P<0.0001) and shorter length of hospital stay (MD, -1.74 days; 95% CI, -3.04 to -0.45; P=0.008). There was no significant difference overall between MIS and OS in terms of functional or pain outcomes. Subgroup analysis of prospective studies revealed MIS had greater operative time (MD, 19.00minutes; 95% CI, 0.90 to 37.10; P=0.04) and lower final functional scores (weighted MD, -1.84; 95% CI, -3.61 to -0.07; P=0.04) compared with OS.Conclusion.Current data suggests spinal fusion by MIS is a safe and effective approach to treat grade I and grade II spondylolisthesis. Moreover, although prospective trials associate MIS with better functional outcomes, longer-term and randomized trials are warranted to validate any association found in this study.