Interlaminar Endoscopic Lumbar Discectomy Using a New 8.4-mm Endoscope and Nerve Root Retractor.

Abstract

Surgical technique. Using an 8.4-mm endoscope and endoscopic nerve root retractor, the interlaminar endoscopic lumbar discectomy (IELD) technique is introduced for lumbosacral levels. Although spine surgeons are familiar with IELD, this technique is only used for L5-S1 disk herniations and requires a wide interlaminar space. Using an 8.4 mm-endoscope, high-speed drill, and endoscopic Kerrison punches, a nerve-root retractor facilitated the simultaneous medial retraction of the nerve root and removal of the disk fragment by the instrument's cannula. Clinical parameters such the visual analog scale scores for back and leg pain, modified Macnab criteria, and Oswestry Disability Index were analyzed. A total of 101 patients were enrolled. The visual analog scale scores for back and leg pain significantly decreased from 6.8±2.1 and 7.8±1.5 to 2.0±0.6 and 1.78±1.1, respectively, at the 1-year follow up (P<0.01). The Oswestry Disability Index score significantly improved from 28.6±11.7 to 7.4±2.9 (P<0.01). Ninety-nine patients (97.1%) showed good outcomes. A new IELD technique and instruments can overcome the drawbacks of existing IELD with adequate bone work and control of the affected nerve root.