Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation

Summary

Presented here is a novel technique of C-arm free transtubular posterolateral decompression for lumbar foraminal stenosis and lateral disc herniation under O-arm navigation.

Abstract

We report a novel technique for C-arm free transtubular L5 nerve decompression under CT-based navigation to reduce the radiation hazard. This procedure is performed under general anesthesia and neuromonitoring. The patient is placed in a prone position on an operating carbon table. A navigation reference frame is placed percutaneously into the contralateral sacroiliac joint or spinous process. Then, CT scan images are obtained. After instrument registration, the L5-S1 foraminal level is confirmed with a navigated probe, and the entry point is marked. Using an approximately 2 cm skin incision, the subcutaneous tissue and muscles are dissected. The navigated first dilator is aimed at the L5-S1 Kambin's triangle, and sequential dilation is performed. The 18 mm tube is used and fixed to the frame. The bone around the Kambin's triangle is removed with a navigated burr. For lateral disc herniation, the L5 nerve root is identified and retracted, and the disc fragment is removed. The navigation-guided tubular endoscopic decompression is an effective procedure. There is no radiation hazard to the surgeon or the operating room staff.

Introduction

Diagnosis and surgeries for lumbar foraminal stenosis (LFS) and lumbar lateral disc herniation (LLDH) at the L5-S1 level are challenging for spine surgeons because of this level's unique structure¹. The iliac crest, broad L5 transverse process (TP), small space between the sacral ala and the L5 TP, and osteophytes make the operating window very narrow². If the bony resection is not enough, inadequate decompression to the L5 nerve root may lead to residual symptoms. Massive bony removal causes postoperative instability. These issues limit surgeons' competencies with foraminal/extraforaminal L5 root decompression. ....

Protocol

This study was approved by the ethics committee of Okayama Rosai Hospital (No. 305).

1. Patient history taking

1. Ensure that the patient has a herniated disc that causes severe sciatica. Usually, the patient will have a history of some prodromal low back pain. They may correlate their symptoms with an episode of trauma.
2. Ask the patient to describe their radiating leg pain, including its location. Also ask them about the activities that make it better or worse when LFS or LLDH is suspected.

2. Physical examination

1. To determine the nerve level....

Results

Eight cases (four men, four women) underwent surgery using this new technique. The average age was 72.0 years, and the average follow-up period was 1.5 years. There were five patients with L5/S1 foraminal stenosis, two patients with L5/S foraminal disc herniation, and one patient with L3/4 foraminal disc herniation. We could perform all surgeries without a C-arm. The average surgical time and blood loss were 143 min ± 14 min and 134 ± 18 mL, respectively.

The average recovery percent.......

Discussion

L5 radicular symptoms are caused mainly by L4-L5 disc herniation or stenosis. These symptoms may also occur due to L5 lumbar foraminal stenosis or L5-S1 lateral lumbar disc herniation (LLDH)⁹. Of all the symptomatic lumbar disc herniations, L5-S1 FLDH accounts for approximately 3%¹⁰. For L5-S1 foraminal lesions, a posterolateral or transforaminal approach is recommended. For this approach, there are three main techniques, such as the microscopic, tube with endoscopic, and f.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
1488 HD 3-Chip camera system	Stryker	1000902487
16mm Endoscope Attachment, Sterile	Medtronic	9560160
18mm Endoscope Attachment, Sterile	Medtronic	9560180
4K 32" surgical display	Stryker	0240-031-050
Adjustable hinged operating carbon table	Mizuho OSI	6988A-PV-ACP	OSI Axis Jackson table
L10 AIM light source	Stryker	1000902487
METRx MED System Endoscope, Long	Medtronic	9560102
METRx MED System Reusable Endoscope	Medtronic	9560101	Metrx
METRx MED System Reusable Endoscope	Medtronic	9560101 M
METRx MED System Reusable Endoscope, Long	Medtronic	9560102
Navigated high speed bur	Medtronic	EM200N	Stelth
Navigated passive pointer	Medtronic	960-559
NIM Eclipse system	Medtronic	ECLC	Neuromonitouring
O-arm	Medtronic	224ABBZX00042000	Intraoperative CT
Stealth station navigation system Spine 7R	Medtronic	9733990	Navigation
Surgical Carts	Stryker	F-NSK-006-00
Tubular Retractor, 16mm	Medtronic	955-524
Tubular Retractor, 16mm, Long	Medtronic	9560216
Tubular Retractor, 18mm	Medtronic	9560118
Tubular Retractor, 18mm, Long	Medtronic	9560218