Percutaneous Unilateral Biportal Endoscopic Spine Surgery Using a 30-Degree Arthroscope in Patients With Severe Lumbar Spinal Stenosis: A Technical Note

BACKGROUND: Unilateral biportal endoscopic surgery (UBESS) for severe lumbar central canal stenosis (LCCS) remains challenging. OBJECTIVE: To describe the use of UBESS with a 30-degree arthroscope in patients with severe LCCS. MATERIALS AND METHODS: Working and viewing portals were created in each unilateral paravertebral area at the target interlaminar level. After ensuring the visual field with a 30-degree arthroscope, effective tissue removal was possible through safe access to the bilateral hypertrophic yellow ligament with minimal osteotomy. The authors evaluated 58 patients and analyzed the clinical outcomes using the visual analog scale, Macnab criteria, and self-predicted walking distance. RESULTS: The visual analog scale scores for low back and leg pains decreased from 7.1 to 1.9 and from 7.9 to 1.6, respectively, at 18 months after the procedure. According to the Macnab criteria, "excellent," "good," and "fair" results were obtained in 51.7%, 41.4%, and 6.9% subjects, respectively. Before surgery, the subjects could walk a mean of 305.8±468.1 m. After surgery, 43.1% of the patients could walk for >1 hour, whereas the remaining patients could walk 1521.8±1831.1 m. CONCLUSION: UBESS using a 30-degree arthroscope can be an efficient and safe intervention in patients with severe LCCS.