Comparative Clinical Efficacy of Unilateral Biportal Endoscopy versus Percutaneous Endoscopic Lumbar Discectomy for Far Lateral Lumbar Disc Herniation: A Retrospective Study

Purpose To systematically compare the clinical outcomes and learning curves of unilateral biportal endoscopy (UBE) and percutaneous endoscopic lumbar discectomy (PELD) in the treatment of far lateral lumbar disc herniation (FLLDH). Methods A retrospective analysis was conducted on 122 patients with FLLDH who underwent spinal endoscopic surgery between January 2022 and July 2024, including 62 cases in the PELD group and 60 cases in the UBE group. All procedures were performed by the same minimally invasive spine surgery team. Perioperative parameters (operative time, intraoperative blood loss, foraminal area, postoperative hospital stay, total cost), visual analogue scale (VAS) scores, Oswestry Disability Index (ODI), and modified Macnab criteria were compared. Learning curves were analyzed using cumulative sum (CUSUM) with operative time as the core variable. All patients were followed for at least 12 months. Results Baseline characteristics were comparable between groups ( P  > 0.05). Both PELD and UBE significantly improved lumbar and leg pain ( P  < 0.05). No significant differences were found in VAS or ODI scores between the two groups preoperatively, at 3 months, or at 12 months postoperatively ( P  > 0.05). Only on postoperative day 1 did the PELD group show a lower VAS back pain score ( P  < 0.05). The excellent/good rate based on modified Macnab criteria did not differ significantly ( P  > 0.05). Perioperative indicators, including operative time, intraoperative and hidden blood loss, and total cost, were all significantly more favourable in the PELD group ( P  < 0.001). No differences were observed in intraoperative fluoroscopy frequency or foraminal cross-sectional area ( P  > 0.05). CUSUM analysis indicated that proficiency was achieved after 24 UBE cases and 38 PELD cases. All complications resolved with conservative treatment. Conclusion Both UBE and PELD are safe and effective for treating FLLDH. PELD offers advantages in perioperative minimally invasive characteristics and cost-efficacy, whereas UBE features a shorter learning curve, facilitating more rapid surgical mastery.