Extreme Lateral Interbody Fusion (XLIF) Including the Segment L5/S1 for Multi-level Lumbar Spondylodesis

Abstract

Study Design: This is a single centre retrospective study of 24 cases of multilevel degeneration of the lumbar spine treated with the XLIF procedure including the level L5/S1. Objective: The purpose of this study is to report the feasibility of including the L5/S1 segment in treating the degenerative lumbar spine using the XLIF procedure and demonstrating the preoperative conditions necessary to do so. Summary of background data: In the last decades, more and more elderly patients suffer from pain and disability due to degenerative instability of the lumbar spine. Spinal fusion procedures, including XLIF, have proven good results despite significant complication and revision rates. Methods: 24 patients (mean age 66 years, range 32 – 89 years) who would be candidates for XLIF surgery at L5/S1 were included. Preoperative anatomical assessment of the iliac crest in relation to the L5/S1 disc space was performed. All patients were operated with the aid of neuromonitoring using a mini-invasive XLIF approach with direct visualisation of the psoas muscle. Complication rates, surgery time, and blood loss were calculated as well as clinical results using the VAS score preoperative, and at 6 weeks, 3 months and 1 year postoperative. Results: The mean postoperative VAS score improved from 7.8 preoperative to 3.1 at one-year followup. There was one case of pseudoarthrosis at the L5/S1 level. There were no new neurological deficits postoperatively. We report a total complication rate of 29%. Conclusion: The XLIF procedure for multilevel lumbar spine fusion is feasible at the L5/S1 level in patients with certain anatomical prerequisites, predominantly in females. The procedure should be done under direct visualization. The clinical outcome and revision rate is comparable to other multilevel fusion techniques