Comparative analysis of three-year outcomes of different interbody fusion approaches for grade I-II lumbar spondylolisthesis with spinal stenosis

Abstract

This study aimed to compare surgical characteristics, complications, clinical and radiographic outcomes among patients undergoing unilateral biportal endoscopic posterior lumbar interbody fusion (UBE-PLIF), percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF), and oblique lumbar interbody fusion (OLIF) for grade I-II lumbar spondylolisthesis (LS) combined with lumbar spinal stenosis (LSS). From July 2019 to May 2022, patients with grade I-II LS combined with LSS were retrospectively included and grouped into the UBE-PLIF, PE-TLIF, and OLIF groups based on the surgical procedure. Baseline characteristics, surgical data, and complications were collected during hospitalization and follow-up. Clinical outcomes, including the Visual Analog Scale (VAS) for low back pain (VAS-back) and leg pain (VAS-leg), the Oswestry Disability Index (ODI), and the Japanese Orthopaedic Association (JOA) score, were assessed preoperatively and at 1, 6, 12, 24, and 36 months postoperatively. Radiographic outcomes, such as intervertebral disc height (IDH), slip percentage, lumbar lordosis angle, and fusion rate, were evaluated at the same timepoints. The PE-TLIF and OLIF groups required longer operative times and greater blood loss than the UBE-PLIF group, with the OLIF group exhibiting the largest incision length, blood loss, and drainage volume ( P  < 0.05). After the 36-month follow-up, the UBE-PLIF group demonstrated significantly better VAS-leg scores at 24 and 36 months, as well as superior ODI and JOA scores at 36 months, compared to the other two groups ( P  < 0.05). Among radiographic outcomes, significant differences were found only in the interbody fusion rate at 6 months and IDH at 36 months ( P  < 0.05), with no differences in other parameters at the remaining timepoints. The total complication rates for UBE-PLIF, PE-TLIF, and OLIF were 13.53%, 18.94%, and 16.79%, respectively, with no significant intergroup differences ( P  > 0.05). UBE-PLIF, PE-TLIF, and OLIF demonstrate comparable safety and efficacy. UBE-PLIF is associated with less blood loss and modest advantages in selected late clinical outcomes, suggesting it is a viable alternative for grade I-II LS with LSS. Given the limitations of retrospective design, further validation through multicenter randomized controlled trials with longer follow-up is warranted.