[A comparative study on the clinical efficacy and safety of unilateral biportal endoscopy versus percutaneous transforaminal endoscopic discectomy in the treatment of recurrent lumbar disc herniation].

<b>Objective:</b> To explore the clinical efficacy and safety of unilateral biportal endoscopic (UBE) and percutaneous transforaminal endoscopic discectomy (PTED) techniques in treating recurrent lumbar disc herniation (RLDH). <b>Methods:</b> This study is a retrospective cohort study. The clinical data were retrospectively collected from 68 patients who underwent surgical treatment for RLDH at Department of Mini-invasive Spinal Surgery, the Third People's Hospital of Henan Province from June 2020 to June 2023. The patients were divided into the UBE group (38 cases) and the PTED group (30 cases) based on the surgical technique used. The drainage volume, surgery duration, and postoperative complications for revision surgeries in both groups were recorded. Visual analogue scale(VAS) and Oswestry disability index (ODI) were used to assess back pain and leg pain degrees and improvements preoperatively, 3 days postoperatively, 3 months postoperatively, and at the final follow-up. The modified Macnab criteria were used to evaluate outcomes at the final follow-up. The data comparison was conducted using independent sample <i>t</i>-test, repeated measures analysis of variance, <i>χ</i>² test or Fisher's exact test. <b>Results:</b> All surgeries were successfully completed. The surgery duration in the UBE group was significantly shorter than in the PTED group, with statistically significant differences ((50.9±10.5)minutes <i>vs.</i>(55.9±12.5)minutes,<i>t</i>=1.234, <i>P</i>=0.001). All patients were followed up for more than 1 year, with a follow-up period of (18.1±5.6) months (range: 12 to 29 months). Both groups showed a significant reduction in VAS and ODI for back and leg pain at all postoperative time points compared to preoperative scores (all <i>P</i><0.05). However, there were no statistically significant differences in VAS of low back pain, lower limb pain score and ODI score over time between the groups (all <i>P</i>>0.05). At the final follow-up, the UBE group had an excellent and good rate of 92.1% (35/38); the PTED group had an excellent and good rate of 86.6% (26/30)(<i>χ</i>²=0.727, <i>P</i>=0.867). One patient in the UBE group and three in the PTED group experienced cerebrospinal fluid leaks, and one patient in the PTED group experienced postoperative leg numbness; all were discharged after conservative treatment. At the final follow-up, lumbar X-rays, CT, and MRI evaluations showed no recurrence or instability at the surgical segments. <b>Conclusions:</b> Both UBE and PTED can achieve good clinical outcomes in the treatment of RLDH through continuous visualization. The choice of surgical method for RLDH should be more precisely tailored to the individual.