The endoscopic technique of percutaneous discectomy is a newly emerging field with advantages of minimal invasiveness and direct intraoperative visualization in surgery for lumbar disc herniation. Conventionally, the posterolateral approach that has a trajectory toward the center of the disc has been performed mainly for contained disc herniation, but it has been less frequently applied for more protruded disc herniations. Recently, transforaminal techniques of percutaneous endoscopic discec- tomy has been proposed to treat more protruded disc herniations. However, the indications for the transforaminal approach have not been well established in detail according to the various situations of more protruded disc herniation. In the authors' experiences of 15 cases of non-contained and extruded lumbar disc herniations including migrated disc, the percutaneous endoscopic procedure by transforaminal approach allowed nearly complete and successful accessibility to the herniated disc. The authors suggest that although more experience needs to be gained, percutaneous transforaminal endoscopic discectomy is a considerably valuable surgical method for complicated lumbar disc herniations that have been considered exclusion criteria with posterolateral endoscopic approach.
