Full Endoscopic Translaminar Approach Using 7 mm Working Endoscope for High Up Migrated Disc Herniation with Severely Collapsed Disc Space: Technical Note

Abstract

The clear indication for the transforaminal approach is simple or low migrated lumbar disc herniation (LDH). The incidence of migration of the disc fragment in LDH varies from 35% to 72%. The high up migrated disc herniation into MacNab’s hidden zone remains technical challenge. We provide a technical note of seldomly performed full endoscopic translaminar approach with its potential indications. A 52 years male patient presented with low back pain with left lower limb radiculopathy for 2 months. Visual analogue scale for back and leg was 2 and 8, respectively. MRI examination revealed high up migrated disc herniation with collapsed disc space at L4-5. Dynamic radiograph was not showing any instability. Based on the preoperative surgical planning working cannula was docked over left L4 lamina perpendicular to horizontal plane. With the help of 3.5 mm endoscopic burr translaminar keyhole was drilled in a concentric manner. The distance between lateral margin of pars and keyhole was intermediately inspected for preservation of adequate bone in pars interarticularis. Though the translaminar key hole subluxated tip of SAP, up-migrated disc fragment was removed. The VAS score of leg reduced significantly from 8 to 2 in immediate postoperative period. At the end of 6 months follow up period patients leg symptoms completely improved with minimal back pain. We measured the width of remaining pars postoperatively and found to be 5 mm. The full endoscopic translaminar approach is valid alternative approach for the high up migrated HNP.