This video demonstrates the step-by-step surgical technique for the minimally invasive laminotomy for contralateral "over-the-top" foraminal decompression. This technique allows for excellent decompression with clearance of the contralateral recess and foramen. In the video, we present the case of a 51-yr-old female patient with a past medical history of left L5-S1 microdiscectomy who presented in clinic with residual/recurrent foraminal disc herniation at L5-S1 compressing the left L5 nerve root. The patient had left lower extremity pain in the left hip and thigh that radiated down the front and side of the leg, as well as tingling and numbness in the left foot. The patient was treated via a L5-S1 microdiscectomy using a portable intraoperative computed tomography scanner, (Airo®, Brainlab AG, Feldkirchen, Germany), combined with 3-dimensional (3D) computer navigation. Patient consent was obtained prior to performing the procedure. The main advantage of this technique is the direct "over-the-top" trajectory to the foraminal pathology that minimizes the need of facet joint resection. The use of 3D navigation facilitates surgical planning and further minimizes facet joint compromise. Particularly, the inferior facet contralateral to the approach side as well as its outer capsular surroundings can be preserved. Recent biomechanical studies have shown that "over-the-top" decompression produces significantly less instability than a traditional open midline laminectomy.
Keywords: 3D navigation; Decompression; Foraminal stenosis; Minimally invasive.
Copyright © 2019 by the Congress of Neurological Surgeons.