RESUMEN
BACKGROUND: Large spacers offer numerous advantages such as higher fusion rates and lower subsidence rates. However, due to the anatomical constraints of the approach, the use of large spacers in biportal endoscopic transforaminal lumbar interbody fusion(BE-TLIF) necessitates an additional incision and special instruments for spacer implantation leading to less frequent use. METHODS: This study has refined several techniques within BE-TLIF. We insert the cage and impact the cage transverse with a special design instrument in the same working portal. This allows for the use of large spacers during BE-TLIF procedures without the need for an auxiliary cage-inserting incision. CONCLUSION: The technique is a straightforward, safe, and minimally invasive method for inserting large cages in the treatment of lumbar instability.