Unilateral biportal endoscopic discectomy via translaminar approach for highly upward-migrated lumbar disc herniation: a technical note and preliminary treatment outcomes.

Study Design: A technical note and retrospective case series. Objective: Highly upward-migrated lumbar disc herniation (LDH) is challenging due to its problematic access and incomplete removal. The most used interlaminar approach may cause extensive bony destruction. We developed a novel translaminar approach using the unilateral portal endoscopic (UBE) technique, emphasizing effective neural decompression, and preserving the facet joint's integrity. Methods: This retrospective study included six patients receiving UBE translaminar discectomy for highly upward-migrated LDHs from May 2019 to June 2021. The migrated disc was removed through a small keyhole on the lamina of the cranial vertebra. The treatment results were evaluated by operation time, hospital stays, complications, visual analog scale (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) score, and modified MacNab criteria. Results: The mean pre-operative VAS for back pain (5.0 ± 4.9), VAS for leg pain (9.2 ± 1.0), JOA score (10.7 ± 6.6), and ODI (75.7 ± 25.3) were significantly improved to 0.3 ± 0.5, 1.2 ± 1.5, 27.3 ± 1.8, 5.0 ± 11.3 respectively at the final follow-up. Five patients had excellent, and one patient had good outcomes according to the Modified MacNab criteria. The hospital stay was 2.7 ± 0.5 days. No complication was recorded. The MRI follow-up showed complete disc removal, except for one patient with an asymptomatic residual disc. Conclusions: UBE translaminar discectomy is a safe and effective minimally invasive procedure for highly upward-migrated LDH with satisfactory treatment outcomes and nearly 100% facet joint preservation. [ABSTRACT FROM AUTHOR]