Abstract:Objective To compare the short-term efficacy of unilateral biportal endoscopic lumbar interbody fusion (ULIF) and minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of lumbar spinal stenosis.Methods Clinical data of 87 patients with lumbar spinal stenosis from April 2020 to June 2022 were retrospectively analyzed. Among them, 43 cases were treated with ULIF (ULIF group) and 44 cases were treated with MIS-TLIF (MIS-TLIF group). The surgical time, intraoperative blood loss, postoperative ambulation time, drainage tube removal time, hospital stay, postoperative complications, visual analog scale (VAS) scores for back and leg pain, as well as Oswestry disability index (ODI) were compared between the two groups.Results Compared with the MIS-TLIF group, the ULIF group had a longer surgical time, with statistically significant difference (P＜0.05). There was no significant difference in intraoperative blood loss, postoperative ambulation time, drainage tube removal time and hospital stay between the two groups (P＞0.05). Two cases in the ULIF group and one case in the MIS-TLIF group experienced cerebrospinal fluid leakage postoperatively, but there were no other complications in either group. There was no statistically significant difference in the incidence of complications between the two groups (P＞0.05). Both groups were followed up for 12 months. The fusion rate in the ULIF group was significantly higher than that in the MIS-TLIF group at 6 months (81.4% vs 59.1%, χ2=5.163, P＜0.05) and 12 months (90.7% vs 68.2%, χ2=6.179, P＜0.05) after surgery.Conclusion For patients with lumbar spinal stenosis, ULIF can achieve similar efficacy to MIS-TLIF, while providing higher decompression efficiency, greater surgical instrument flexibility, and more thorough intervertebral space treatment. However, ULIF has a longer surgical time.