Is Stand-Alone Anterior Lumbar Interbody Fusion a Safe and Efficacious Treatment for Isthmic Spondylolisthesis of L5-S1?

Study Design: A systematic review. Objective: The objective of this study was to determine the safety and efficacy of stand-alone anterior lumbar interbody fusion (sa-ALIF) for the treatment of symptomatic isthmic spondylolisthesis of L5-S1 by assessing the level of available clinical and radiographic evidence. Methods: A systematic review utilizing Medline, Embase, and Scopus online databases was undertaken. Clinical, radiographic, and adverse outcome data were extracted for the relevant isthmic spondylolisthesis cases with the intention of undertaking a meta-analysis. Results: The database search between January 1980 and December 2015 yielded 23 articles that concerned sa-ALIF for isthmic spondylolisthesis of L5-S1. Only in 9 of the 23 articles data could be extracted specific to sa-ALIF for isthmic spondylolisthesis of L5-S1. There was considerable inconsistency in the standards for reporting outcomes of the surgery due to which meta-analysis could not be undertaken, and hence each article was reviewed. Conclusions: There was insufficient evidence to support the safety and efficacy of sa-ALIF for the treatment of isthmic spondylolisthesis of L5-S1. Although sa-ALIF is widely documented in the literature, there was insufficient evidence to support its use in treating this specific pathology. The unique pathological and anatomical situation that isthmic spondylolisthesis of L5-S1 presents must be recognized and its treatment with sa-ALIF should be well thought out.