Posterolateral percutaneous endoscopic lumbar foraminotomy for L5-S1 foraminal or lateral exit zone stenosis. Technical note.

The purpose of this study was to determine the efficacy and feasibility of posterolateral percutaneous endoscopic lumbar foraminotomy (PELF) for foraminal or lateral exit zone stenosis of the L5-S1 level in the awake patient. Twelve consecutive patients with L5-S1 foraminal stenosis and associated leg pain underwent PELF between May 2001 and July 2002. Under fluoroscopic guidance, posterolateral endoscopic foraminal decompression was performed using a bone reamer, endoscopic forceps, and a laser. Using this new technique, the authors removed part of the hypertrophied superior facet, thickened ligamentum flavum, and protruded disc compressing the exiting (L-5) nerve root. Clinical outcome was measured using the Macnab criteria. The mean follow-up period was 12.9 months. All the patients were discharged within 24 hours. Satisfactory (excellent or good) results were demonstrated in 10 patients. There was no complication. The PELF procedure provides a simple alternative for treating lumbar foraminal or lateral exit zone stenosis in selected cases. The authors found that the posterolateral endoscopic approach to the L5-S1 foramen was usually possible and that using a bone reamer to undercut the superior facet was effective.