Abstract
This video aims to describe an endoscopic surgical approach for accessing difficult to reach pathology such as disc herniations after previous surgery. The relatively small size of endoscopic instruments facilitates significant freedom of movement inside the spinal canal. The authors have experience with interlaminar approaches for contralateral pathology such as disc herniations, recurrent disc herniations, spinal stenosis, and facet cysts. The advantages of starting from the opposite side of the canal in a revision situation include the ability to establish a clear plane between the dura and the borders of the canal and visualize the disc from a different angle than the index operation. Contralateral approaches to residual or recurrent herniations can be performed with an "over the top" technique, navigating dorsal to the thecal sac to reach the far side of the canal. In the associated video we demonstrate a novel technique, a contralateral transaxillary endoscopic approach to a recurrent disc herniation at the L5-S1 level in a young male collegiate wrestler. In our experience, we have found this particular approach to be useful in patients with an early take off of the S1 nerve root which creates a large axillary window. In several instances this technique has allowed us to inspect the area of the reherniation from both the axilla and over the top of the thecal sac. This particular patient has a large recurrence 2 years after an open microscopic hemilaminotomy and discectomy. In this instance, an approach was chosen that navigates dorsal to the S1 nerve root and ventral to the thecal sac, starting on the opposite side of the spinal canal from the herniation. This approach is described as a contralateral interlaminar transaxillary discectomy.