Thoracoscopic Diskectomy

33 Thoracoscopic Diskectomy

Victor Lo, Alissa Redko, Ashley E. Brown, Daniel H. Kim, and J. Patrick Johnson

33.1 Introduction

Video-assisted thoracoscopic surgery (VATS) emerged to treat spinal disorders in 1993.1,2,3 Current uses of thoracoscopy in spinal procedures include spinal canal decompression (e.g., diskectomy, corpectomy), spinal biopsy, deformity correction, and sympathectomy. The thoracoscopic technique parallels an open thoracotomy procedure in that a ventrolateral approach is taken through the chest cavity, providing a full and direct vertebrolateral view of the vertebra and thecal sac. The benefits of the thoracoscopic procedure include minimal tissue retraction, reduced postoperative pain, and decreased hospital length of stay.4,5,6 The thoracoscopic approach can also be adapted for instrumentation and fusion if required.7 In addition, innovation in intraoperative navigation technology has led to the incorporation of image-guided VATS.8,9 This chapter describes the indications and procedure for thoracoscopic diskectomy.

33.2 Indications for Thoracic Diskectomy

The incidence of clinically significant thoracic disk herniation is reported to be as low as 1 per million or 0.25 to 0.75% of all ruptured disks.10,11 Radiculopathy due to thoracic disk herniation typically causes both axial back pain and radicular pain that manifests as paraspinal muscular spasms and bandlike radiating chest wall pain.

Nonsurgical management of these lesions with nonsteroidal anti-inflammatories, epidural steroid injections, and physical therapy has been successful in treating many patients with solely radicular symptoms. Nonsurgical treatment of tolerable thoracic radiculopathy for 3 to 6 months is reasonable given that a large proportion of cases will improve without surgical intervention.

Although there is no consensus regarding thoracic disk removal, surgery is generally reserved for patients who failed conservative treatment of primarily radicular symptoms or who have myelopathy, especially if it is progressive or severe.

Approaches for thoracic diskectomy are dorsolateral (e.g., transpedicular), lateral (e.g., costotransversectomy, lateral extracavitary, parascapular), ventrolateral (e.g., transthoracic/thoracoscopic, retropleural), and ventral (e.g., transsternal). Approach selection depends on the anatomical location of the disk herniation. All soft herniated disks, calcified lateral disks, and mildly calcified centrolateral disks can usually be treated with posterolateral approaches (Fig. 33.1). Centrolateral disks that are densely calcified or certain mildly calcified disks that require any retraction of the spinal cord for diskectomy should be considered for treatment primarily with a ventrolateral or lateral approach (Fig. 33.2). When a transthoracic approach is indicated, one may consider a thoracoscopic approach as well.

33.3 Contraindications to Thoracoscopic Diskectomy

Contraindications include:

• Respiratory insufficiency (i.e., inability to tolerate single-lung ventilation)

• Pleural symphysis

• Failed prior open ventral surgery

• Thoracic empyema

• Previous thoracotomy

• Previous tube thoracostomy

• Bullous lung pathology with reduced lung function

33.4 Imaging for Thoracic Disk Disease

MRI is the optimal modality for assessing the thoracic vertebra, intervertebral disk, and neural elements. MRI can characterize the herniated disk’s location with respect to the spinal canal (i.e., central, paracentral, lateral; Fig. 33.2).

CT defines the bony anatomy and can determine whether the herniated disk is calcified (Fig. 33.3) or the posterior longitudinal ligament is calcified (Fig. 33.4). CT myelography is useful when the patient is unable to tolerate, or has a contraindication to, MRI (Fig. 33.5).

Plain film studies of the thoracic and lumbar spine can be used as an intraoperative reference for localizing the herniated disk.

33.5 Surgical Instruments

The endoscopic equipment needed for a thoracoscopic diskectomy procedure is available in hospital operating rooms where general surgical and gynecological laparoscopy and/or general thoracic endoscopy is performed.12 The equipment includes:

• Radiolucent surgical table

• Fluoroscopy equipment (C-arm)

• Endoscope

image 5-mm or 10-mm diameter optical working channel

image 0°, 30°, and 45° angled cameras (Fig. 33.6)

• Surgical drill

image Extended drill attachments

image Pistol grip provides some rotational and angular stabilization (Fig. 33.7a)

image Coarse diamond drill bit and round cutting bit (Fig. 33.7b)

• Extended long-handled spine instruments (Fig. 33.8)

image Kerrison rongeurs

image Straight and angled curets

image Pituitary grasper

image Nerve hook

image Penfield dissectors

image Dental dissector

• Suction-irrigator

image Available from the standard endoscopic equipment set

image Extended Frazier suction tip can also be used

• Endoscopic instruments

image Endo shears

image Bipolar endoscopic cautery

Mar 29, 2020 | Posted by in ORTHOPEDIC | Comments Off on Thoracoscopic Diskectomy
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