Unilateral biportal endoscopic lumbar interbody fusion: Radiographic and clinical outcomes in grade I lumbar spondylolisthesis.

To evaluate the radiographic and clinical outcomes of unilateral biportal endoscopic lumbar interbody fusion (ULIF) in patients with grade I lumbar spondylolisthesis, 30 patients underwent ULIF between January 2023 and January 2024. Clinical and radiographic outcomes were analyzed, including operative time, intraoperative blood loss, hospital stay, fusion rate, and laboratory indices (Hb, CRP, CPK). All procedures were successfully completed without intraoperative complications. The mean operative time was 199.7 ± 36.5 minutes, blood loss 60.7 ± 29.6 mL, and hospital stay 9.2 ± 3.7 days. Low back pain Visual Analogue Scale decreased from 6.63 ± 1.00 to 0.83 ± 0.80, leg pain Visual Analogue Scale from 6.47 ± 1.41 to 0.63 ± 0.67, and Oswestry Disability Index from 58.47 ± 12.86 to 18.87 ± 7.67 at 12 months. The fusion rate at final follow-up was 100%. Laboratory findings indicated a transient decrease in Hb and increases in CRP and CPK on POD1, with recovery by POD3. ULIF is a promising short-term option for grade I lumbar spondylolisthesis, demonstrating effective reduction, spinal decompression, minimal soft tissue injury, and high short-term fusion success.