LAUSR

BACKGROUND Mainstay of treatment for symptomatic adjacent segment disease (ASD) has consisted of revision with posterior decompression and fusion. This carries significant morbidity and can be technically difficult. An alternative is stand-alone lateral lumbar interbody fusion (LLIF) which may avoid complications associated with revision surgery. We describe the largest cohort of patients treated with LLIF for ASD to our knowledge. METHODS We conducted a retrospective cohort study on all patients who underwent transpsoas LLIF for ASD at a single academic center between 2012 and 2019. Postoperative improvement was measured using the visual analog scale (VAS) and the Oswestry disability index (ODI). RESULTS 44 patients who underwent LLIF for ASD were identified. Median age was 65. Median time from index surgery to ASD development was 78 months. Median levels fused via LLIF was one. Our median follow-up was 358 days. At follow-up, the median VAS back pain score was 0 (mean 0.884), median VAS leg pain score was 1 (mean 0.953), and median ODI was 8. The median improvement for VAS back pain was 8, for VAS leg pain was 6, and for ODI was 40. No patients suffered new neurologic symptoms postoperatively. Of the 17 patients who initially presented with non-pain neurologic symptoms, eight (47.1%) experienced complete resolution of symptoms, five (29.4%) experienced only some improvement. CONCLUSIONS To our knowledge this is the largest cohort study of patients to date evaluating stand-alone LLIF for ASD. Our patient outcomes show it is safe and effective with low risk of morbidity.