A Modified Translaminar Osseous Channel-Assisted Percutaneous Endoscopic Lumbar Discectomy for Highly Migrated and Sequestrated Disc Herniations of the Upper Lumbar: Clinical Outcomes, Surgical Indications, and Technical Considerations

Figure 2

Intraoperative endoscopic view before decompression. A circular osteal groove (black arrows) is made with a trepan on the lamina of the vertebra to site a working sheath (a). The exiting nerve root (stars) is shifted laterally by the disc protrusion fragments (black arrows). The dural sac (crosses) is also compressed by the protrusion fragments, and the protruding fragments (long arrow) can be easily accessed under direct visualization by the endoscope (b).

(a)

(b)