Assisted full-endoscopic spine surgery for lumbar spinal stenosis: Technical note and learning curve

Lumbar spinal stenosis (LSS) causes disabling back and radicular pain. Full-endoscopic spine surgery offers minimally invasive decompression, but uniportal and biportal approaches have limitations. Assisted full-endoscopic spine surgery (AFESS) combines the advantages of both techniques to enhance decompression while preserving facet joints. Can AFESS provide effective decompression with high facet preservation for LSS, and what is the learning curve for this technique? We retrospectively reviewed 33 patients with single-level LSS treated with AFESS, divided into initial (20 cases) and advanced (13 cases) phases. Outcomes assessed at a minimum 6-month follow-up included operative time, facet joint preservation ratio, complications, and visual analog scale (VAS) scores for back and leg pain. Operative time decreased significantly from the initial to the advanced phase (mean 99 vs 72 minutes; p