Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters

Abstract

BACKGROUND CONTEXT Lumbar fusion surgery can be performed through either anterior, lateral or posterior approaches. Although the relative advantage of anterior lumbar surgeries for the restoration of sagittal balance in spinal deformity is well-acknowledged, the comparative utility of these approaches in maintaining sagittal alignment following single level lumbar fusion remains unclear. PURPOSE A systematic review of the current literature was performed to assess the relative change in sagittal lumbar parameters including whole lumbar lordosis (WLL), segmental lumbar lordosis (SLL) and disc height (DH) following lumbar fusion using various approaches. STUDY DESIGN/SETTING Systematic review and meta-analysis. PATIENT SAMPLE All subjects in studies reporting imaging outcomes following single-level lumbar fusion, according to inclusion and exclusion criteria. OUTCOME MEASURES Lumbar sagittal parameters (SLL and WLL) and DH. METHODS A computerized literature search of all articles published up to April 17, 2017 was performed using PubMed and Cochrane databases. The following keywords were used: “anterior lumbar interbody fusion”, “ALIF”, “posterior lumbar interbody fusion”, “PLIF”, “trans-foraminal lumbar interbody fusion”, “TLIF”, “lumbar 360° fusion”, “circumferential lumbar fusion”, “combined anterior and posterior lumbar fusion”, “extreme lateral interbody fusion”, “LLIF”, “lateral lumbar interbody fusion”, “LLIF”, “direct lateral interbody fusion”, “DLIF”, “extraforaminal lumbar interbody fusion”, “ELIF”, with different combinations of operators including “AND”, “NOT” and “OR”. All studies were scored based on Methodological Index for NonRandomized Studies (MINORS) criteria. Pairwise comparisons of the fusion approach effect sizes were performed for the three imaging parameters. RESULTS A total of 1,563 articles under “ALIF”, 2,075 articles under “PLIF”, 1,032 articles under “TLIF”, 1,082 articles under “LLIF” and 894 under “circumferential lumbar fusion” were identified. The articles were further stratified on the basis of number of fusion levels. Only studies reporting relevant imaging outcomes following single-level fusion for degenerative pathologies were included in the final analysis. Using this strategy, a total of 14, 27, 25, 11 and 3 studies were included under ALIF, PLIF, TLIF, minimally invasive-TLIF and LLIF, respectively. Based on pairwise comparisons, ALIF significantly improved WLL and DH restoration as compared to all the other fusion modalities [ALIF vs. PLIF:2.5 (0.5–4.6) vs. 1.5 (0.2–2.4), p CONCLUSIONS Based on a systematic review of the literature, ALIF offers a significantly improved restoration of lumbar sagittal parameters following single-level lumbar fusion.