Comparison of Clinical Outcomes and Muscle Invasiveness between Unilateral Biportal Endoscopic Discectomy and Percutaneous Endoscopic Interlaminar Discectomy for Lumbar Disc Herniation at L5/S1 Level

OBJECTIVE: Both unilateral biportal endoscopic discectomy (UBED) and percutaneous endoscopic interlaminar discectomy (PEID) could achieve favorable outcomes for lumbar disc herniation (LDH). There are limited studies comparing the two different methods of endoscopic discectomy. The objective was to comprehensively compare the clinical outcome and muscle invasiveness of UBED and PEID for the treatment of LDH at L5/S1 level with at least 1‐year follow‐up. METHODS: The retrospective cohort study enrolled 106 LDH patients of L5/S1 level from January 2018 to December 2020. There were 51 patients who underwent UBED (22 males and 29 females, 43.8 ± 14.2 years old) and 55 patients underwent PEID (28 males and 27 females, 42.3 ± 13.8 years old). Clinical outcomes and surgical invasiveness were compared between the two groups for at least 1 year follow‐up. Clinical outcomes included visual analogue scale (VAS) scores, Oswestry Disability Index (ODI), complications, recurrence of LDH, intraoperative anesthesia time, operative time, number of intraoperative fluoroscopies, and postoperative length of stay. Surgical invasiveness was evaluated with serum CPK level and change rate of lean multifidus cross‐sectional area (LMCSA). Independent‐sample t test and paired sample t test were used to compare continuous data. Chi‐square test and Fisher's precision probability tests were used to analyze the categorical data. RESULTS: Both groups achieved favorable clinical outcomes at the last follow‐up, including VAS and ODI (all Ps <0.05). The intraoperative anesthesia time for UBED was longer, but with no difference of operative time. As for intraoperative fluoroscopy times (2.5 vs 2.4), postoperative length of stay (2.1 vs 2.0 days), postoperative complications (5.9% vs 3.6%), there were also no significant difference. The serum CPK level and change rate of LMCSA for UBED was higher than PEID at postoperative 1st day. At the last follow‐up, there was no significant difference in the change rate of LMCSA between the two groups (P = 0.096). CONCLUSIONS: Both UBED and PEID could achieve favorable clinical outcomes for the treatment of L5/S1 LDH. Despite UBED is more invasive, the radiological manifestation of paraspinal muscle invasiveness was equal at last follow‐up with at least 1 year. UBED is a safe and innovative alternative choice for treatment of LDH at L5/S1 level.