Endoscopic Extraforaminal Lumbar Discectomy

Abstract

Lateral lumbar disk herniation, which is classified as foraminal or extraforaminal herniation, can cause lower extremity pain in patients who have no evidence of nerve compression lesions in the spinal canal. It accounts for 10% of all lumbar disk herniations. Full-endoscopic lumbar discectomy (FELD) is a minimally invasive surgical technique in which an endoscope and related instruments are directly inserted into the lesion through an 8 mm cannula, without the need for dissection of the spinal structures around the nerve. Using the posterolateral approach, FELD allows direct access to the lateral disk herniation without excessive resection of the lumbar facet joint. Lateral disk herniations are often associated with degenerative spondylolisthesis or foraminal stenosis; therefore, it is sometimes necessary to perform foraminoplasty. Lateral and ventral sides of the superior articular process are shaved anteromedially at a 45° angle with a high-speed drill until the proximal side of the pedicle of the lower vertebra, and the annular surface of the disk appears, preserving the facet joint. Within the Kambin’s triangle, the ganglion is usually pushed upward dorsally by the fragment of the herniated disk from the annular fissure in the intervertebral foramen. The approach to the base of the pedicle of the lower vertebra, which is the farthest from the exiting nerve root within the Kambin’s triangle, can help prevent damage to the exiting nerve root. FELD can be performed under local anesthesia and is an effective surgical method for patients with comorbidities, owing to its low invasiveness.