Comparative study of the learning curves for percutaneous endoscopic interlaminar lumbar discectomy and unilateral biportal endoscopy techniques.

Abstract

Background: Minimally invasive spinal surgery techniques, such as Percutaneous Endoscopic Interlaminar Lumbar Discectomy (PEID) and Unilateral Biportal Endoscopy (UBE), have been developed to reduce surgical morbidity and enhance patient recovery. Although both techniques demonstrate promising clinical outcomes, the learning curves required for surgeons to achieve proficiency with these methods remain unclear.

Objective: To compare the learning curves of PEID and UBE in the treatment of lumbar disc herniation.

Methods: We conducted a retrospective analysis of 173 patients who underwent either PEID (n = 94) or UBE (n = 79), performed by two independent surgeons between January 2020 and January 2022. Eligible patients were aged 18-75 years, diagnosed with lumbar disc herniation, and had no previous spinal surgeries at the affected level. Metrics analyzed included operative time, intraoperative blood loss, postoperative recovery, complication rates, and clinical outcomes, assessed using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores.

Results: The PEID group demonstrated significantly shorter operative times (99.96 ± 34.74 min vs. 116.52 ± 47.20 min, P < 0.05) and less blood loss (20.85 ± 11.06 ml vs. 80.19 ± 22.81 ml, P < 0.01) compared to the UBE group. Both techniques showed significant improvements in VAS and ODI scores postoperatively, with no significant differences between the groups at any follow-up points. Learning curve analysis revealed that operative times for PEID stabilized at approximately 70 min after about 40 cases, while UBE stabilized at around 65 min after approximately 35 cases. Complication rates were low, and patient satisfaction was high in both groups. According to the Modified MacNab criteria, 83% of patients in the PEID group and 79.7% in the UBE group achieved excellent outcomes, while only 5.3% and 3.8% of patients experienced fair or poor outcomes in the PEID and UBE groups, respectively.

Conclusion: Both PEID and UBE are effective minimally invasive techniques for the treatment of lumbar disc herniation, offering comparable clinical outcomes and low complication rates. However, PEID is associated with shorter operative times and reduced intraoperative blood loss. Understanding the learning curves of these techniques is crucial for surgeons to improve proficiency and optimize patient outcomes.