A simple technique of accessing the L5-S1 disc space for transforaminal endoscopic spine surgery.

Transforaminal endoscopic spine surgery is increasingly used to treat a range of spinal conditions. The success of the surgery requires an accurate insertion of the guide needle and a precise placement of the working cannula and endoscope. However, such a precise placement is challenging for many surgeons to achieve when the pathology is located at the L5-S1 level. On the basis of our years of experience with performing transforaminal endoscopic spine surgery, we have developed a simple technique to help surgeons safely access the L5-S1 level. The technique has been proven intuitive and easy for experienced as well as inexperienced surgeons to learn. The key steps of the technique involve identifying an appropriate entry point on the skin and choosing an accurate trajectory angle for insertion. The purpose of this chapter is to report how to easily identify the entry point and choose a trajectory angle depending on the patient's anatomic characteristics.