Laminectomy for the Removal of Thoracic Ossification of the Ligamentum Flavum (TOLF) Using Ultrasonic and Conventional Osteotomes

Summary

We present a methodology for using an ultrasonic osteotome combined with a conventional osteotome for laminectomy in thoracic ossification of the ligamentum flavum. This is a relatively safe and easy-to-learn method that avoids the perioperative complications associated with the conventional method.

Abstract

Thoracic ossification of the ligamentum flavum (TOLF) is a common cause of progressive thoracic myelopathy. TOLF is typically treated with surgical decompression. A variety of surgical techniques, including laminoplasty, laminectomy, and lamina fenestration, are used for the effective treatment of TOLF. However, traditional methods are associated with a substantial risk of perioperative complications, including dural laceration and/or iatrogenic spinal cord injury. Therefore, it is important to develop an efficient and secure surgical technique for TOLF. Herein, we describe a method for laminectomyperformed at the thoracic spine using an ultrasonic osteotome combined with a conventional osteotome. This technique can reduce intraoperative complications. This is a relatively safe and easy-to-learn method that should be recommended for the treatment of TOLF.

Introduction

Thoracic ossification of the ligamentum flavum (TOLF) is one of the major causes of thoracic spinal stenosis and has been established as the primary cause of thoracic myelopathy^1,2,3. TOLF is characterized by the replacement of the ligamentum flavum by ectopic new bone formation. The incidence of TOLF is as high as 36% in Japan and 63.9% in China. Most patients show slow progression to symptomatic thoracic canal stenosis or thoracic myelopathy⁴. Decompression is the only effective treatment for TOLF once it becomes symptomatic since conservative treatm....

Protocol

Ethical approval was obtained from the Medical Ethics Committee of the authors' hospital. Informed consent was obtained from each patient.

1. Inclusion/exclusion criteria and preoperative preparation

1. Include patients with the following preoperative symptoms: unable to walk steadily, numbness of the lower limbs, atrophy of the lower limbs, leg weakness, uncontrolled movement of the lower extremities, or sphincter dysfunction, etc., as well as signs and imaging data consistent with thoracic myelopathy.
2. Exclude patients based on the following criteria: the presence of cervical spinal stenosis or lumba....

Results

Representative case results
On the first postoperative day, the CT scans revealed that the ossification had been fully removed, and the spinal cord had been completely decompressed (Figure 5). The patient could walk steadily. The muscle strength of both lower limbs was 5. The patient was discharged 3 days after the operation.

A total of 71 patients were enrolled in the study. All surgeries were carried out satisfactorily. The mean duration of .......

Discussion

Laminectomy is the conventional treatment method for thoracic ossified ligamentum flavum. However, the improper use of traditional bone-cutting equipment, such as high-speed drills and revolving burrs, can result in nerve thermal injury, grasping the soft tissue, tearing the dura mater, and mechanical injury^15,16,17. An ultrasonic osteotome is a novel bone-cutting tool used for precise osteotomies. This device allows for bone di.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
C-arm X-ray machine	GE	20192060063	/
Cera styptica	Johnson&Johnson (China) Medical Equipment Co., Ltd	W810T	/
Conventional osteotome	Suzhou qingniu medical instrument co.	10012.01	/
Cottonoids	Piaoan Holding Group Co., Ltd	20182640073	/
Fluid gelatin	Johnson&Johnson (China) Medical Equipment Co., Ltd	20183142459	/
Gelatin sponge	B.Braun Melsungen AG	20163642299	/
Jackson–Pratt drainage	Suzhou Weikang Medical Equipment Co., Ltd	20162140955	/
Kerrison Rongeurs	Jinzhong Medical Instruments Co., Ltd	2100888	/
Nerve dissector	Jinzhong Medical Instruments Co., Ltd	p23110	/
Pedicle screw	Medtronic	76446545	/
Towel clamps	KEWEIDUN	10058468134417	/
Ultrasonic Osteotomy Surgical System	SMTP Technology Co.	FD880A	/
Unipolar/bipolar electrotome	Shanghai Hutong Electronics Co., Ltd	20143251899	/