Endoscopic Decompression of Periradicular Fibrous Tissue in Lumbar Canal Stenosis: A Case Report

Lumbar canal stenosis (LCS) is a common degenerative pathology in middle-aged patients. Symptoms of LCS arise from compression of the traversing root due to narrowing of the lateral recess, which is attributed to hypertrophy of the ascending facet and thickened ligamentum flavum. Decompression of these structures is the main management goal for these patients. However, in patients with neurological deficits, recovery of motor weakness remains uncertain despite adequate decompression. We report a case of a 52-year-old female patient diagnosed with L4–5 LCS and right foot drop (L4:2/5, L5:0/5 Medical Research Council [MRC] grade) who underwent surgical decompression using unilateral biportal endoscopy. Intraoperatively, we observed that even after adequate decompression of the neural elements, there was persistent blanching of the L5 root. Upon further evaluation, we noted periradicular fibrous tissue encasing the L5 root. Careful removal of these fibrous tissues improved the vascular supply of the L5 root, demonstrating that the tissues had exerted a compressive effect on the nerve root. Postoperatively, motor power partially recovered (L4, L5: MRC grade 3/5) at the 6-week follow-up. Our case highlights the importance of careful attention to fibrous elements in the epidural space using endoscopy, which could enhance the overall outcomes following decompression in LCS.