Unilateral biportal endoscopic versus microscopic discectomy in degenerative lumbar spinal stenosis: A prospective cohort study

Abstract

Background: Unilateral biportal endoscopic discectomy (UBE) and microendoscopic discectomy (MED) are well-established minimally invasive techniques for managing single-segment degenerative lumbar spinal stenosis (DLSS). However, current evidence from evidence-based medicine remains insufficient to conclusively demonstrate the comparative advantages of these methods.

Methods: A total of 145 patients diagnosed with single-segment DLSS were enrolled from the spinal surgery department of Xinjiang Bazhou People's Hospital between January 2022 and August 2024. Fourteen patients were lost to follow-up, leaving 131 valid cases. Participants were divided into 2 groups: UBE (n = 70) and MED (n = 61), based on the surgical approach. The study compared the demographic and clinical characteristics of both groups (gender, age, disease duration, height, weight, BMI, and affected segment), perioperative metrics (operation time, blood loss, and hospital stay), and clinical outcomes at various time points (preoperatively, 3 days postoperatively, 1-month postoperatively, 3 months postoperatively, 1-year postoperatively, and 2 years postoperatively), including visual analogue scale (VAS) scores for back and leg pain, Oswestry disability index (ODI) scores, and imaging parameters (preoperative and postoperative disc height and dural sac expansion area).

Results: All patients completed follow-up for over 2 years. The UBE group demonstrated significantly shorter operation times, reduced blood loss, and shorter hospital stays compared to the MED group (P < .05). No significant differences in VAS scores for back and leg pain or ODI scores were found between the groups at preoperative and postoperative time points (P > .05). Both groups showed significant improvements in VAS scores for back and leg pain and ODI scores at all postoperative time points relative to preoperative levels (P < .05). No significant differences in dural sac expansion area or disc height (preoperative and postoperative) were noted between the groups (P > .05).

Conclusion: Both UBE and MED are effective treatments for single-segment DLSS, achieving substantial spinal canal decompression and improvement in clinical symptoms. UBE, however, offers advantages over MED in terms of shorter surgical time, reduced blood loss, and shorter hospital stays.

Keywords: MED; UBE; degenerative lumbar spinal stenosis; microendoscopic discectomy; unilateral biportal endoscopic.

Figure 1.

Flowchart of the trial design.

Figure 2.

Typical cases. (A–D) Preoperative (A and B) and postoperative MRI (C and D) of UBE group patients; (E–H) preoperative (E and F) and postoperative MRI (G and H) of MED group patients.