Comparative effectiveness and safety of posterior lumbar interbody fusion, Coflex, Wallis, and X-stop for lumbar degenerative diseases: A systematic review and network meta-analysis.

Posterior lumbar interbody fusion and lumbar interspinous non-fusion technique are common surgical procedures for lumbar degenerative diseases, but the effectiveness and safety of these two techniques are still unclear. We performed this network meta-analysis to evaluate the comparative effectiveness and safety of posterior lumbar interbody fusion and the three commonly used interspinous devices including Coflex, Wallis, and X-stop for lumbar degenerative diseases. Randomized controlled trials and cohort studies comparing among posterior lumbar interbody fusion, Coflex, Wallis, and X-stop for lumbar degenerative diseases were identified using the databases including PubMed, the Cochrane Library, Web of Science, the China National Knowledge Infrastructure, Chinese Science and Technology Periodical Database, and Wanfang data. A network meta-analysis was performed using R 3.4.3 software. 27 studies with 2241 patients were included. The results of network meta-analysis revealed that no significant differences in Oswestry Disability Index, Visual Analogue Scale, Japanese Orthopedic Association Scores, and posterior disc height were found among posterior lumbar interbody fusion group, Coflex, Wallis, or X-stop. However, compared with posterior lumbar interbody fusion, the three interspinous process devices presented with significantly more range of motion in surgical segment, but no significant difference was found among these three interspinous process devices. Node-splitting analysis showed no significant inconsistency in our network meta-analysis. We concluded that compared with posterior lumbar interbody fusion, Coflex, Wallis and X-stop had the same effectiveness in relieving pain, improving quality of life, recovering disc space height and lumbar function, but may lower incidence of adjacent segment degeneration.