Endoscopic and Microscopic Interlaminar Discectomy for the Treatment of Far-Migrated Lumbar Disc Herniation: A Retrospective Study with a 24-Month Follow-Up

PURPOSE: Percutaneous endoscopic lumbar discectomy for the treatment of far-migrated lumbar disc herniation (LDH) is clinically challenging. The aim of this study was to compare the efficacy and safety of interlaminar endoscopic lumbar discectomy (IELD) and interlaminar microscopic lumbar discectomy (IMLD) for the treatment of far-migrated LDH. MATERIALS AND METHODS: We retrospectively analyzed 50 consecutive cases of far-migrated LDH treated by IELD or IMLD. Clinical data and outcomes were assessed before the operation and 1 day and 3, 12, and 24 months after the surgery using the visual analog scale (VAS) and Oswestry disability index (ODI). Modified MacNab criteria were used to evaluate patient satisfaction at the 24-month follow-up. RESULTS: A significant reduction in leg pain and improvement in ODI (P<0.01) were observed in both groups after surgery. Lower back pain (LBP) was reduced at 24 months postsurgery in the IELD group (P<0.05) but not in the IMLD group (P>0.05). There were significant intergroup differences in VAS LBP score at 1 day and 24 months postsurgery (p=0.01 and 0.02, respectively) and in ODI at 24 months (p=0.03). The rate of excellent or good outcome was 90.32% with IELD and 78.95% with IMLD (p=0.55). Hospital stay and time to ambulation were shorter in the IELD group than in the IMLD group, but the former had a longer operative time (p<0.01). Low and comparable complication rates were reported in the IELD (16.13%) and IMLD (10.53%) groups (p=0.70). CONCLUSION: Both IELD and IMLD achieve favorable clinical results in the treatment of far-migrated LDH, with only minor complications. Compared to IMLD, LBP was significantly reduced with IELD presumably because it involved less trauma.