Clinical and Radiologic Outcomes of Unilateral Biportal Endoscopic Lumbar Interbody Fusion Compared With Conventional Posterior Lumbar Interbody Fusion on the Treatment of Single-segment Lumbar Spinal Stenosis With Instability, a 2-year Follow-up Study.

Study Design: Retrospective cohort study.

Objective: To investigate the clinical and radiologic outcomes of unilateral biportal endoscopic lumbar interbody fusion (ULIF) for single-segment lumbar spinal stenosis with instability.

Background: Unilateral biportal endoscopic technology has developed rapidly, and ULIF is a new type of minimally invasive fusion surgery. However, there remains a lack of sufficient evidence regarding its clinical efficacy. By comparing it with posterior lumbar interbody fusion (PLIF) surgery, its clinical efficacy can be evaluated.

Materials And Methods: In total, 110 (ULIF group, 54; PLIF group, 56) patients were included. Perioperative indicators were compared between the groups. Clinical efficacy, Visual Analog Scale (VAS) scores for back and leg pain, and Oswestry Disability Index scores were compared. Surgical complications, intraoperative dural tears, nerve root injury, surgical hematoma, and reoperation were assessed. The postoperative clinical test indicators were white blood cell count and C-reactive protein, procalcitonin, and interleukin-6 levels. Imaging results, cage loosening, screw loosening, and intervertebral fusion rate were evaluated.

Results: The surgical time was significantly longer in the ULIF group than in the PLIF group. The postoperative ambulation time, length of hospital stay, and postoperative drainage volume were shorter in the ULIF group than in the PLIF group. There were no differences in the VAS scores for leg pain and Oswestry Disability Index scores, but there were statistically significant differences in the VAS scores for low back pain between the groups. The white blood cell count and C-reactive protein, procalcitonin, and interleukin-6 levels were significantly lower in the ULIF group than in the PLIF group. None of the patients showed any loosening of the fusion cage or any loosening or breakage of the screws. There was no difference in the lumbar interbody fusion rate.

Conclusions: ULIF has several advantages, but its surgical time is significantly prolonged.