This protocol introduces a modified eggshell surgical technique used for treating sclerosing thoracic disc herniation.
Sclerosing thoracic disc herniation refers to a condition in which the intervertebral disc in the thoracic region protrudes and becomes calcified, causing compression on the spinal cord and/or nerve roots. Sclerosing herniation of the thoracic disc poses a significant danger as it can lead to serious complications like paraplegia during or after surgery. Iatrogenic spinal cord injury is a common risk for individuals diagnosed with sclerosing thoracic disc herniation due to the inflexible protrusion of the sclerosing disc into the spinal canal and its adhesion to the ventral side of the dural sac. The challenging and crucial aspect of the surgery is how to safely and efficiently eliminate the hardened tissue. The eggshell method is a surgical procedure that addresses the kyphosis abnormality of the spinal column by excavating the vertebral body via the pedicles and subsequently inserting the kyphotic fracture block into the excavated vertebral body. In this article, a revised surgical method using the eggshell technique will be presented for the treatment of sclerosing thoracic disc herniation. The surgical procedure briefly involves hollowing out the anterior intervertebral space of the hardened disc tissue to create an eggshell-like structure, with the sclerotic tissue forming the posterior wall. Subsequently, the sclerotic disc tissue is pushed into the hollow intervertebral space to achieve complete decompression of the ventral spinal cord. The safety and effectiveness of this approach for treating sclerosing thoracic disc herniation have been confirmed.
In medical situations, thoracic disc herniation is categorized into three types: central, paracentral, and lateral. Spinal cord injury (SCI) symptoms are predominant in central protrusion, whereas radicular symptoms are commonly observed in lateral protrusion. Central and paracentral protrusions account for approximately 70%. Predominant segments affected are T11 and T12 (26%), with 75% of thoracic disc herniation occurring between T8 and T12, and the subsequent thoracic vertebrae exhibiting the highest incidence1,2,3.
When nerve compression occurs, the thoracic spinal canal typically becomes smaller than the cervical and lumbar spinal canal, resulting in reduced space for spinal cord escape4,5,6. Once patients exhibit symptoms, many are accompanied by signs of spinal cord injury7,8. The effectiveness of conservative treatment is generally poor, necessitating eventual surgical intervention.
The primary objective of thoracic disc herniation surgery is to alleviate pressure on the spinal cord8. Surgical approaches include two types – anterior and posterior approaches. Anterior surgery directly alleviates compression on the spinal cord, while posterior surgery indirectly relieves this compression. Even for skilled surgeons capable of directly removing compression from the anterior sclerotic disc, anterior surgery is technically demanding and poses a high risk to patients. Complications, including spinal cord injury, worsening symptoms, leakage of cerebrospinal fluid (CSF), and infection, were observed in a range of 9.6% to 40.8%9,10,11.
A major factor contributing to the elevated surgical risk is the relative fragility of the dorsal subarachnoid space and the ventral spine's dura. Even slight increased backward traction on the spinal cord can lead to disastrous outcomes12. Furthermore, detaching the dural sac from the thoracic spine and applying pressure often results in electrophysiological warning occurrences, significantly increasing the chances of spinal cord damage13,14,15. Additionally, anterior thoracic spinal stenosis surgery often requires thoracotomy and is more traumatic.
Posterior surgery, achieved by removing the posterior structure of the spinal canal, allows the spinal cord to have a certain backward movement space, indirectly relieving compression from the sclerotic disc to the spinal cord9,16,17. Both surgical approaches can yield certain surgical effects, but anterior surgery, influenced by the presence of lungs, blood vessels, and nerves, increases the surgical difficulty18. In contrast, posterior surgery's effect on spinal cord decompression is limited for patients9,16,17, and complete relief of compression may not be achieved. However, the advantage lies in the absence of vital vascular nerves and organs at the back, making it easily exposed and convenient for surgical operations15. Nevertheless, there is still debate on which surgery constitutes the gold standard for thoracic disc herniation.
Severe symptoms can manifest when the spinal cord or nerve roots are compressed due to the herniation and calcification of the thoracic intervertebral disc, a condition known as sclerosing thoracic disc herniation19. Because of the typical positioning of the hardened disc on the ventral side of the spinal cord, direct visual removal of the hardened disc is often unfeasible. Our team previously reported a posterior modified eggshell surgical technique for treating sclerosing thoracic disc herniation20. This modified eggshell technique, performed under direct vision, enables complete spinal cord decompression in all directions. The modified eggshell approach can completely remove the sclerotic disc, thereby reducing the risk of SCI. Treating sclerosing thoracic disc herniation with this surgical method is both safe and efficient. This article introduces and demonstrates the surgical procedure.
The primary application of this surgical procedure is to achieve thorough decompression of the spinal cord from all angles, utilizing the posterior pathway of the thoracic spine. Serious complications are common in patients with thoracic disc herniation, primarily due to the anatomy of the thoracic spine. According to Min et al.18, anterior decompression using an anterior method has a definite impact but requires a challenging procedure. Furthermore, the extensive trauma it induces, substantial di…
The authors have nothing to disclose.
None.
Bipolar electrocoagulation tweezers | Juan'en Medical Devices Co.Ltd | BZN-Q-B-S | 1.2 mm x 190 mm |
Bone wax | ETHICON | W810T | 2.5 g |
Curette | Qingniu | 20739.01 | 300 x Ø9 x 5° |
Curette | Qingniu | 20739.02 | 300 x Ø9 x 15° |
Curette | Qingniu | 20739.03 | 300 x Ø9 x 30° |
Curette | Qingniu | 20739.04 | 300 x Ø9 x 45° |
Double jointed forceps | SHINVA | 286920 | 240 mm x 8 mm |
High frequency active electrodes | ZhongBangTianCheng | GD-BZ | GD-BZ-J1 |
Laminectomy rongeur | Qingniu | 2054.03 | 220 x 3.0 x 130° |
Pedicle screw | WEGO | 800386545 | 6.5 mm x 45 mm |
Pedicle screw | WEGO | 800386550 | 6.5 mm x 50 mm |
Rod | WEGO | 800386040 | 5.5 mm x 500 mm |
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