# Precise localization value of lumbar lamina and ligamentum flavum boundaries in minimally invasive tubular resection of intraspinal schwannomas

## TL;DR

This study shows that using specific spinal landmarks helps surgeons precisely remove tumors with minimal invasion, leading to good patient outcomes.

## Contribution

The study demonstrates the effectiveness of lumbar lamina and ligamentum flavum boundaries as anatomical landmarks for minimally invasive schwannoma resection.

## Key findings

- All tumors were successfully resected without neurological complications.
- Patients showed significant improvement in disability scores after surgery.

## Abstract

This study aimed to assess the utility of lumbar lamina and ligamentum flavum boundaries as anatomical landmarks for the precise localization and resection of lumbar intraspinal schwannomas using a minimally invasive tubular approach.

We conducted a retrospective analysis of 17 patients who underwent surgical resection between September 2021 and September 2023. Preoperative imaging was used to determine the optimal lamina landmarks relative to the tumor’s poles or midpoint. The boundaries or specific sites of the ligamentum flavum subsequently guided the precise drilling of the bone window. We recorded intraoperative parameters, including retractor inclination angle, operative time, and blood loss. Patient outcomes were assessed during a two-year follow-up using the Oswestry Disability Index (ODI), MRI to evaluate resection, and X-ray to assess spinal stability.

All tumors were successfully resected without neurological complications. The mean operative time was 119.7 ± 14.7 min, mean blood loss was 47.1 ± 11.9 mL, and the mean retractor angle was 6.3 ± 2.5°. After a mean follow-up of 30.9 ± 1.6 months, ODI scores showed significant improvement, decreasing from 31.5 ± 5.4% to 14.9 ± 3.4%. Postoperative MRI confirmed gross-total resection in all cases, and X-rays revealed no spinal instability.

The boundaries of the lumbar lamina and ligamentum flavum are reliable and effective anatomical landmarks. Utilizing these landmarks facilitates precise, minimally invasive resection and is correlated with favorable short-term outcomes.