Overcoming the Challenge of Controlled Total Facetectomy in Uniportal Endoscopic Transforaminal Interbody Fusion: A Direct-Visualization Crown-Reaming Technique

Endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) is increasingly used as a minimally invasive fusion technique; however, controlled total facetectomy under endoscopic visualization remains technically demanding. Conventional reaming methods are often partially blind and fluoroscopy-dependent, and these limitations may increase the risk of neural irritation or endplate violation. We describe a direct-visualization crown-reaming technique for controlled total facetectomy and disc-space preparation during Endo-TLIF. Sequential foraminal enlargement and facetectomy are performed using a hollow crown reamer under continuous endoscopic visualization, allowing real-time identification of neural structures. Disc removal and endplate preparation are completed while preserving subchondral bone integrity, and the hollow reamer configuration permits simultaneous autologous bone graft collection. Direct-visualization crown reaming is a feasible technique for controlled total facetectomy during uniportal Endo-TLIF and may improve procedural control and facilitate neural structure identification. Further studies are warranted to evaluate its safety and potential clinical benefits.