Biportal Endoscopic Paraspinal Approach for Foraminal and Extraforaminal Disc Herniations

Abstract

For lumbar foraminal stenosis, the biportal endoscopic technique, which can reach deeper into the foramen less invasively, is becoming widespread and surpassing microscopic surgery in popularity. The best advantage of the biportal endoscopic paraspinal approach is that it can reach deep into the foramen less invasively. Further, this technique provides a good field of vision in a high magnification endoscopic view which is familiar to most spine surgeons and a clearing view by continuous irrigation for good decompression of foraminal stenosis. There are several technical tips about the biportal endoscopic paraspinal approach. First, the target point is below the pedicle, which is located on top of the superior articular process (SAP) and lateral to the isthmus on an anteroposterior view of the C-arm fluoroscopy. Second, the surgical anatomy is first identified as a landmark, including the lateral part of the isthmus, the lower part of the transverse process, and the top of the SAP. Third, if removal of the SAP medial part is enough, the disc can be removed without much root retraction. Finally, taking great care to maintain fluid output is important to prevent increasing intracranial pressure and retroperitoneal fluid collection.