Minimally Invasive Lateral Thoracic and Lumbar Interbody Fusion with Expandable Interbody Spacers for Spine Trauma—Indications, Complications and Outcomes

<b>Background</b>: Lateral lumbar or thoracic interbody fusion (LLIF) is increasingly considered for anterior column reconstruction and restoring segmental lordosis in degenerative, infectious, or deformity conditions. Reports about using LLIF with expandable interbody spacers for spine trauma are scarce. <b>Methods</b>: In this retrospective, single-center observational cohort study, we reviewed all patients treated by an expandable LLIF interbody spacer (ELSA^® Expandable Integrated LLIF Spacer, Globus Medical Inc) for trauma indication at our spine center between September 2018 and January 2024. The primary outcome measures were fusion rate at 12 months, change in segmental sagittal Cobb angle, and clinical outcome according to the MacNab criteria. Secondary outcomes included adverse events and complications. <b>Results</b>: We identified <i>n</i> = 21 patients with a mean age of 48.3 (standard deviation (SD) 15.7), 47.6% were female. LLIF was mostly performed at T11/12 (<i>n</i> = 4; 19.1%) and T12/L1 (<i>n</i> = 10; 47.5%). Indications were AO Spine type A2 (<i>n</i> = 4, 19.1%), A3 (<i>n</i> = 14; 66.7%) or A4 fractures (<i>n</i> = 3; 14.3%) with ligamentous (B2-type) in eight (38.1%) and hyperextension (B3-type) injury in one patient (4.8%). Surgery included the release of the anterior longitudinal ligament in four cases (19.1%). Intraoperative AEs were noted in <i>n</i> = 1 (4.8%), postoperative AEs in <i>n</i> = 3 (14.3%) at discharge, <i>n</i> = 4 (19.1%) at three, and <i>n</i> = 2 (9.5%) at twelve months. Segmental sagittal Cobb angle changed from 1.3° (preoperative) to 13.3° at twelve months (<i>p</i> < 0.001). Functional outcome was excellent/good in <i>n</i> = 15 (71.4%; four missing) at 12 months. The fusion rate at the LLIF level was 100% at the 12-month follow-up. <b>Conclusions</b>: LLIF with expandable interbody spacers for spine trauma (off-label use) is safe, promotes solid fusion (100% fusion rate at 12 months), and enables correction of sagittal segmental Cobb angle (mean improvement of 12°), with good or excellent clinical outcomes in most patients (71.4%).