Neurospine.  2023 Dec;20(4):1513-1523. 10.14245/ns.2346572.286.

A Modified Laminotomy for Interlaminar Endoscopic Lumbar Discectomy: Technical Report and Preliminary Results

• Feng Z
• Wu Y
• Wu H
• Jon TG
• Yuan Y
• Chen Z
• Wang Y

• KMID: 2549874
• DOI: http://doi.org/10.14245/ns.2346572.286

Abstract

Objective
To introduce a technique of laminotomy using a common trephine to enlarge the interlaminar space at L4/5 segment for interlaminar endoscopic lumbar discectomy (IELD) and report the anatomical basis of this procedure, technical details, as well as primary clinical outcomes of a consecutive patient cohort with L4/5 lumbar disc herniation (LDH).
Methods
On anteroposterior fluoroscopy, the intersection of the medial edge of the inferior articular process and the inferior endplate of L4 vertebra was taken as the target. Using a common trephine, laminotomy was performed to remove a big portion of the posterior wall of the canal under the guidance of endoscopy. From June 2018 to December 2021, the consecutive patients who underwent L4/5 IELD were prospectively studied. Clinical outcomes were assessed at the day before surgery, 1 day, 1 month, 3 months, 12 months after surgery, and the last follow-up. Numerical Rating Scale, Roland-Morris Disability Questionnaire (RMDQ), and MacNab criteria were used to evaluate back and leg pain, the quality of life, and clinical efficacy, respectively.
Results
There were 64 men and 44 women, with an age of 50.3 ± 14.9 years. The operating time was 74.54 ± 17.42 minutes. The mean follow-up time was 32.7 ± 18.6 months (range, 12–64 months). The complications of IELD included numbness, neck pain, and recurrence. Both leg pain (6.2 ± 1.9 vs. 1.8 ± 0.8, p < 0.001) and back pain (3.1 ± 2.3 vs. 1.7 ± 0.9, p < 0.001) quickly improved after this procedure and maintained (1.1 ± 1.5, 1.1 ± 1.3) at final follow-up. Physical disability due to back pain, as assessed using RMDQ, was improved remarkably after surgery (15.0 ± 5.8 vs. 2.9 ± 4.1, p < 0.001). In addition, MacNab outcome grade was evaluated as good-to-excellent in 96 cases (88.9%).
Conclusion
A convenient technique of laminotomy using a common trephine was proposed for the L4/5 IELD. It can efficiently enlarge the interlaminar entry to perform endoscopic discectomy. This procedure is particularly suitable for treating LDH with concomitant lumbar spinal stenosis and migrated herniated disc.

Keyword

Interlaminar endoscopic lumbar discectomy; Laminotomy; Trephine; Spinal stenosis; Migrated disc herniation; Clinical efficacy