Feasibility of Recurrent Herniation Surgery with Biportal Endoscopic Discectomy: A Comparison of Biportal Endoscopic Discectomy and Microscopic Discectomy for Recurrent Disc Herniation

Objective: In this study, we aimed to compare the clinical outcomes of unilateral biportal endoscopic (UBE) lumbar discectomy and open lumbar microdiscectomy (MD) for recurrent disc herniation. Methods: Ninety patients who underwent discectomy, including 44 and 46 who underwent UBE and MD, respectively, were enrolled. All surgeries were performed between March 2020 and April 2023. Only patients with single-level recurrence were included; patients with multilevel recurrence or unstable disease, as well as those who had undergone surgery less than 6 months prior, were excluded. Visual analog scale (VAS) scores, recurrence rates, and complications were compared between the groups. Results: The average follow-up periods were 19.09 and 20.45 months in the UBE revision and MD revision discectomy groups, respectively. The mean bleeding loss and hospital stay were shorter in the UBE group than in the MD group. Postoperative short-term back pain was lower in the UBE group (VAS score, 3.32) than in the MD group (VAS score, 7.89) (p<0.001). Radiating pain showed similar patterns in both groups at all time points. Recurrence was more frequent in the MD group; however, this difference did not reach statistical significance, likely owing to the small sample size (p=0.677). Similarly, incidental durotomy occurred less frequently in the UBE group (6.8% vs. 8.7%), but this difference was not statistically significant. Conclusion: Both UBE and MD could achieve good long-term outcomes; however, UBE revision was superior in terms of short-term back pain, bleeding loss, and length of hospital stay after surgery.