Background: Chronic low back pain (CLBP) is one of the most common causes of disability worldwide, affecting more than 619 million people as reported in the Global Burden of Disease 2020. Its prevalence ranges from 4% to 20% depending on age, sex, and occupational exposures, with significant impacts on quality of life and healthcare systems. Unilateral biportal endoscopic (UBE) spine surgery has shown favorable outcomes as a minimally invasive technique, but local data in the Philippines remain scarce. This study was conducted to describe the clinical and functional outcomes of CLBP patients who underwent UBE surgery in our setting. Objective: To determine the functional outcomes and complication rates of chronic low back pain patients who underwent UBE spine surgery.

Methods: A retrospective cohort study was conducted on 56 patients with chronic low back pain secondary to lumbar stenosis, lumbar disc herniation, or degenerative disc disease. Pain and disability were assessed using the Numerical Rating Scale and Oswestry Disability Index (ODI) preoperatively and at follow-up. Complications related to the procedure were recorded and analyzed.

Results: A total of 56 patients with chronic low back pain underwent Unilateral Biportal Endoscopic (UBE) spine surgery between June 2023 and December 2024. The majority were males (53.6%) with a mean age of 47.18 years, and most were overweight or obese. Lumbar disc herniation was the most common diagnosis (66.1%), followed by lumbar stenosis (26.8%) anddegenerative disc disease (7.1%). Significant improvement in pain was observed across all groups, with Numerical Rating Scale (NRS) scores decreasing from moderate to severe preoperative levels to minimal or no pain by six months postoperatively. Functional outcomes measured by the Oswestry Disability Index (ODI) also improved substantially, showing marked gains in mobility and daily activity. The overall complication rate was 8.9%, including one reoperation, one dural tear, and one pneumonia-related mortality, with most complications being minor and manageable.

Conclusion: UBE spine surgery is a safe and effective minimally invasive alternative to open procedures for chronic low back pain secondary to lumbar stenosis, disc herniation, and degenerative disc disease. It provides significant pain relief, functional recovery, and an acceptable complication profile, supporting its broader application in spine surgery practice.