Abstract:[Objective] To explore the clinical efficacy of percutaneous endoscopic medial foraminal discectomy (PEMFD) with or with-out Kirschner wire positioning for the treatment of lumbar disc herniation (LDH). [Methods] A retrospective study was conducted on 93 pa-tients who underwent PEMFD using a visualizing trephine for LDH in our hospital from June 2019 to January 2022. Based on doctor-pa-tient discussion preoperatively, 48 patients received PEMFD with Kirschner wire anchoring positioning, while the remaining 45 patients un-derwent the conventional PEMFD. The perioperative, follow-up, and imaging data were compared between the two groups. [Results] All pa-tients in both groups had operation performed successfully with no serious complications . The positioning group proved significantly superi-or to the conventional group in terms of surgical operation time [(44.9±3.2) min vs (54.3±3.3) min, P<0.001] and fluoroscopy frequency[(3.4±1.1) times vs (7.0±1.4) times, P<0.001], whereas there were no statistically significant differences in incision length, intraoperativeblood loss, postoperative walking time, incision healing grade and hospital stay between the two groups (P>0.05). All patients were followedup for 12~18 months, with an average of (14.4±5.0) months, and there was no statistically significant difference in the time to resume fullweight-bearing activity between the two groups (P>0.05). The VAS and ODI scores significantly decreased in both cohorts over time (P<0.05), and there was no statistically significant difference in VAS and ODI scores between the two groups at any time points accordingly (P>0.05). According to the modified Macnab's criteria, there was no statistically significant difference in the excellent and good rate of clinicalresults between the two groups at the latest follow-up (89.6% vs 88.9%, P>0.05). Regarding imaging, the spinal canal area significantly increased (P<0.05), while the intervertebral space height and lumbar lordosis angle remained unchanged in both group at the latest follow-upcompared with those preoperatively (P>0.05). At the corresponding time points, there was no statistically significant difference in the above-said imaging measurement indicators between the two groups of patients (P>0.05). In addition, there was no significant change in the Pfir-rmann grade of involved discs in both groups at the last follow-up (P>0.05), and no statistically significant difference in Pfirrmann grade be-tween the two groups at any corresponding time point (P>0.05). [Conclusion] The Kirschner wire anchoring positioning in PEMFD for pos-terior endoscopic treatment of LDH can significantly improve surgical efficiency.