Endoscope-Assisted Minimally Invasive Interlaminar Lumbar Decompression for Spinal Stenosis.

Background: Lumbar stenosis is characterized by a narrowing of the spinal canal in association with progressive degenerative changes in the lumbar spine and surrounding structures, including hypertrophy of the ligamentum flavum (LF).

Objectives: The aim of this study was to examine the usefulness of endoscope-assisted interlaminar lumbar decompression (EILD) for patients with lumbar stenosis and hypertrophy of the LF.

Study Design: Retrospective study.

Setting: Department of Anesthesiology and Pain Medicine, Neurosurgery at Wooridul Spine Hospital.

Methods: A total of 51 patients were enrolled in this study. Outcomes were evaluated at baseline and at 2 weeks and 6 months postprocedure via the Numeric Rating Scale, Oswestry Disability Index (ODI), and Zurich Claudication Questionnaire (ZCQ).

Results: Mean posttreatment pain scores at 2 weeks and 6 months were significantly lower, and ODI scores were significantly decreased compared with baseline. ZCQ scores were also significantly decreased compared with pretreatment surveys. Two patients required reoperation within one month. At postprocedure 6 months, a>/= 50% reduction in pain score was recorded in 26 (80%) of 51 patients, and there was >/= 40% reduction in ODI score in 82% of patients. No serious complications including epidural bleeding, dural or neural injuries, or infection were recorded.

Limitations: This study lacked secondary outcome substantiation. In addition, the follow-up period was short (< 6 months), and no patients had postprocedure magnetic resonance imaging. The number of patients was also small.

Conclusions: EILD provided good outcomes and may be a reasonable treatment option for carefully selected patients with hypertrophy of the LF.

Key Words: Spinal stenosis, ligamentum flavus, hypertrophy, decompression, endoxcope, minimally.