Translaminar Microendoscopic Herniotomy for Cranially Migrated Lumbar Disc Herniations Encroaching on the Exiting Nerve Root in the Preforaminal and Foraminal Zones

STUDY DESIGN Case series. PURPOSE The aim of this study was to describe translaminar microendoscopic herniotomy (TL-MEH) for cranially migrated lumbar disc herniations encroaching on the exiting nerve root in the preforaminal and foraminal zones and to report preliminary results of the procedure. OVERVIEW OF LITERATURE Conventional interlaminar approaches for preforaminal and foraminal lumbar disc herniations result in extensive removal of the lamina and facet joint to remove disc fragments safely. More destructive approaches increase the risk of postoperative segmental instability. METHODS TL-MEH is a minimally invasive procedure for herniotomy via the translaminar approach using a microendoscopic technique. TL-MEH was performed in seven patients with a cranially migrated lumbar disc herniation encroaching on the exiting nerve root. The disc fragments were located in the preforaminal zone in four patients, and in the preforaminal and foraminal zones in three. RESULTS All patients experienced immediate relief from symptoms after surgery and satisfactory results at the final follow-up. Surgical complications, such as a dural tear, nerve injury, and surgical site infection, were not investigated. CONCLUSIONS TL-MEH seemed to be an effective and safe alternative minimally invasive surgical option for patients with a cranially migrated lumbar disc herniation encroaching the exiting nerve root in the preforaminal and foraminal zones.