Oblique lumbar interbody fusion combined with anterolateral screw fixation for treating severe lumbar spinal stenosis: Case series

It is controversial for indirect decompression like oblique lumbar interbody fusion (OLIF) for treating severe lumbar spinal stenosis (SLSS). OLIF combined with anterolateral screw fixation (AF) can achieve decompression and fixation by single incision, which is minimally invasive. In this study, we aimed to evaluate the effectiveness and safety of OLIF-AF for treating SLSS. A retrospective study which comprised patients diagnosed with L4-5 SLSS of Schizas grade C or D caused by degenerative conditions who underwent L4-5 OLIF-AF with a follow-up of 24 months. Preoperative Visual Analog Scale score of low-back pain and leg pain, and Oswestry Disability Index, disc height, foraminal area, ligamentum flavum thickness, difference of left and right facet angle, and cross-sectional area (CSA) were compared to their 1 day, 3 months, 12 months, and 24 months postoperative counterparts. Eighty-two patients of L4-5 SLSS underwent OLIF-AF were included in this retrospective study. Ligamentum flavum thickness thinned from 4.94 ± 1.20 mm to 4.20 ± 0.95 mm after the operation, and 3.91 ± 0.78 mm and 3.87 ± 0.75 mm (all P < .05) at 12 and 24 months postoperatively. CSA expanded from 52.44 ± 15.38 mm2 to 103.98 ± 20.44 mm2 on postoperative day 1, and expand to 115.77 ± 20.04 mm2 and 117.71 ± 20.83 mm2 (all P < .05) at each annual follow-up. Visual Analog Scale score of low-back pain improved from 6.40 ± 0.99 to 2.56 ± 0.85 at 3 months postoperatively, then reached 1.55 ± 0.69 and 1.12 ± 0.64 (all P < .05) at each annual follow-up. Visual Analog Scale score of leg pain gradually improved from 6.16 ± 1.25 to 2.37 ± 0.82, 1.36 ± 0.71, and 1.10 ± 0.69 (all P < .05) at each time point. Oswestry Disability Index increased from 37.54 ± 6.01 to 18.81 ± 4.38 (P < .05) after surgery. And recovered to 12.42 ± 2.44 (P < .05) and 10.58 ± 1.63 (P < .05) at 1 and 2 years postoperatively. OLIF-AF can effectively restore disc height, foraminal area, and CSA, reducing lumbar rotation, thinning the hypertrophic ligamentum flavum, significantly improving patients' pain and function, and maintaining efficacy, indicating that OLIF-AF may be a safe and effective treatment for SLSS.