Perioperative and Long-Term Outcomes in Endoscopic and Tubular Minimally-Invasive Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis

Introduction: Endoscopic lumbar fusion is a relatively new technique, similar to minimally invasive (MIS) lumbar fusion, that aims to reduce invasiveness for patients. Endoscopic techniques have yet to see widespread adoption in the United States compared to MIS fusion. This study seeks to compare endoscopic and MIS lumbar fusion within the existing literature.

Methods: In accordance with PRISMA guidelines, the MEDLINE, CENTRAL, and EMBASE databases were searched for all relevant papers. Title, abstract, and full text screening was conducted by two reviewers and ties were resolved by a third. Primary comparative studies in English of adults undergoing lumbar spinal fusion with either technique were included. Random effects models were used to conduct meta analyses on reported outcome variables.

Results: The initial search yielded 496 studies. Following screening, 15 studies totaling 1,173 patients were selected. The endoscopic group was found to have longer pooled operative time (mean difference [MD] 27 mins, p < 0.001) and fluoroscopy time (MD 12.45 seconds, p< 0.001), less blood loss (MD -72.81 mL, p < 0.01) and drain output (MD -35.74 mL, p < 0.001), and shorter LOS (-1.53 days, p < 0.01) compared to the MIS group. The endoscopic group also had lower VAS-B scores within one week following surgery (MD -1.18, p< 0.001) and at one year (MD -0.07, p = 0.01), but VAS-L and ODI were comparable between groups at both time points.

Conclusion : Endoscopic and MIS lumbar fusion have comparable pain and functional outcomes at one year, however, the former results in lower postoperative back pain and shorter hospital length of stay. These improvements over MIS may yield greater immediate patient satisfaction which can lead to better long-term outcomes. This supports greater US adoption of endoscopic spine techniques through efforts such as hospital investment in hardware, incorporation into neurosurgical training programs, and innovation-forward legislation.