Preoperative localization of herniated thoracic discs using myelo-CT guided transpleural puncture: technical note

The utility of internal spinal marking for intraoperative localisation: A systematic review

BACKGROUND

Incorrect level spinal surgery is an avoidable complication, with significant ramifications. Several pre-operative spinal marking techniques have been described to aid intraoperative localisation.

METHODS

A systematic search of Ovid MEDLINE, and EMBASE was performed from inception to July 2022. All publications describing cases of internal spinal marking were included for further analysis. 22 articles describing 503 patients satisfied our eligibility criteria.

RESULTS

A number of localisation techniques, including endovascular coiling (n = 16), fiducials (n = 177), dye (n = 109), needle/fixed wire (n = 199), cement (n = 4), and gadolinium tubes (n = 1) were described. The highest rates of technical success were observed with endovascular coiling, fiducials, cement and dye (100 %), and complication rates were lowest with endovascular coiling, fiducials and cement (0 %).

CONCLUSIONS

Overall, internal spinal marking was effective and safe. When considering practicality and efficacy, fiducial marking appears the optimal technique, as it can be performed in the outpatient setting under local anaesthesia. This review demonstrates the need for more targeted investigation into localisation methods in spinal surgery.

A modified vertebroplasty technique for intraoperative thoracic spine localisation: a technical report

The aim is to illustrate the modified vertebroplasty technique as a fixed marker for intraoperative thoracic spine localisation. Open and minimally invasive surgery in the thoracic spine has been correlated with a disproportionately high rate of wrong-level spinal surgery in pathologies where a focal deformity or fracture is absent. Spinal markers have evolved with time, and vertebroplasty as a spinal marker was initially described in 2008. A significant disadvantage is that the cement in the vertebral body and pedicle may preclude a more extensive osteotomy or subsequent instrumentation at the level of interest. We demonstrate the modified vertebroplasty technique, which introduces percutaneous polymethylmethacrylate cement two levels below the thoracic disc herniation on the contralateral side to the surgical approach using standard vertebroplasty methods. The vertebroplasty was performed as an outpatient procedure, and the radiopaque cement was instantaneously located on intraoperative fluoroscopy, identifying the correct level above. The modified vertebroplasty technique is a quick, safe and accurate method of thoracic spine localisation, facilitating the room required for the bony exposure and instrumentation if needed.

Thoracoscopic Microdiscectomy with Preservation of Rib and Costovertebral Joint

INTRODUCTION

Thoracic disc herniations (TDH) may cause major morbidity. While thoracoscopic microdiscectomy (TMD) is an excellent technique, postoperative band-like pain is an important drawback.

MATERIAL AND METHODS

We performed 181 consecutive TMDs (including 39 high-risk cases) with preservation of rib and costovertebral joint (CVJ). We shave a few mm of the rib, drill straight to target, and avoid opening the canal before the TDH is completely free and (in case of giant TDHs) internally debulked, creating initial decompression and limiting epidural venous oozing. Subsequently, we gently mobilize and remove the residual TDH while avoiding leverage.

RESULTS

Skin-to-skin time was <90' in 64, 90-120' in 48, >120' in 20, unknown in 10, and 162' mean in 39 high-risk procedures. Blood loss was <100 mL in 76, <250 mL in 48, and 537 mL mean in 39 high-risk procedures. The technique was successfully applied in all (including nine dural repairs) without a single conversion. We observed an increased neurological deficit in two (1.1%) and inadequate decompression in merely one (wrong level). Complications (mainly pulmonary) were few and managed conservatively, except for a segmental artery pseudoaneurysm treated endovascularly. We observed a substantial decrease in acute and chronic postoperative pain.

DISCUSSION

The technique is fast, straightforward, minimizes bone resection and blood loss, improves orientation, safely and effectively deals with any TDH, and prevents postoperative band-like pain as the CVJ is preserved.

CONCLUSION

We hope this technique will find broader acceptance among a new generation of spine surgeons to benefit patients suffering TDH-related myelopathy or merely intractable pain.

Use of a radiopaque localizer grid and methylene blue staining as an aid to reduce radiation exposure

Background: Localization of small femur lesions for resection can be challenging and may be associated with the need for significant fluoroscopic imaging and tissue dissection. This study was performed to evaluate the use of a radiopaque localizer grid along with methylene blue staining for resection of small femur lesions in children, and to determine the effectiveness of this effectiveness at reducing radiation exposure and tissue injury.Material and methods: A radiopaque localizer grid was used to identify the body surface site of bone lesions, and then 0.02-0.03 mL of methylene blue was injected into the bone lesions. After skin incision, the blue bone tissue was found and complete lesion resection performed.Results: A radiopaque localizer grid was utilized to plan the point of entry for lesion resection. The average operation time was shorter, and the C-arm was used less frequently, and the incision length was shorter in the grid and methylene blue group compared with the control group.Conclusion: A radiopaque localizer grid is a simple and practical device for efficient localization of the skin entry site, and methylene blue accurately pinpoints bone lesions, reducing radiation exposure and tissue injury.

Elevated inflammatory cytokine expression in CSF from patients with symptomatic thoracic disc herniation correlates with increased pain scores

BACKGROUND

The pathophysiology of pain in patients with symptomatic thoracic disc herniation (TDH) remains poorly understood. Mere mechanical compression of the spinal cord and/or the exiting nerve root by a prolapsed disc cannot explain the pathogenesis of pain in all cases. Previous studies report a direct correlation between the levels of proinflammatory cytokines in disc biopsies and the severity of leg pain in patients with lumbar disc herniation. A similar correlation in patients with TDH has not been investigated.

PURPOSE

To correlate the cerebrospinal fluid (CSF) expression of cytokines and pain-related amino acids with preoperative pain scores in patients with symptomatic TDH.

STUDY DESIGN

A prospective human study of CSF samples and clinical outcome scores.

METHODS

Using enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC), we determined inflammatory cytokine levels (TNF-α, IL-1β, and IL-10) and amino acid levels (glutamate, aspartate, gamma-aminobutyric acid, glycine, and arginine) in CSF samples from 10 patients with TDH and 10 control subjects who did not suffer an inflammatory disease nor pain related to spinal cord compression and subsequently correlated these levels with preoperative pain scores. Differences between both groups were evaluated by a Mann-Whitney U test. In order to estimate the correlation between cytokine or amino acid expression and pain scores, data were analyzed using a linear regression analysis.

RESULTS

No inflammatory cytokines were found in CSF samples from control subjects, whereas TNF-α, IL-1β, and IL-10 were detectable by ELISA in all CSF samples from patients with TDH. TNF-α and IL-10 but not IL-1β levels moderately correlated with preoperative pain scores. Elevated TNF-αlevels positively correlated with high pain scores; elevated IL-10 levels negatively correlated with high pain scores. Amino acids were detectable in all samples from both groups. There were no significant differences between the groups in any of the amino acids measured with HPLC.

CONCLUSION

Increased proinflammatory cytokine expression is associated with elevated pain scores in patients with symptomatic TDH. On the other hand, there is no conclusive correlation between the intensity of pain and the local or systemic presence of amino acids associated with pain transmission.

Crippling upper back pain after whiplash and other motor vehicle collisions caused by thoracic disc herniations: report of 10 cases

STUDY DESIGN

Retrospective analysis of a prospectively collected database of thoracoscopic microdiscectomies performed at the Maastricht University Medical Center.

OBJECTIVE

Many victims of a motor vehicle collision (MVC) report crippling upper back pain resistant to conservative treatment. Although this pain is often regarded as nonspecific or related to a whiplash type of cervical spine injury, this study demonstrates it may be caused by a thoracic disc herniation.

SUMMARY OF BACKGROUND DATA

Recent literature on bodily pain after whiplash and other MVCs has shown that most patients rather than pain confined to the posterior neck area (0.4%) report pain in multiple body areas, the most frequently affected region being the posterior trunk region, including the posterior neck, posterior shoulder, upper back, lumbar, and buttock areas. Although several patterns determining most variance in pain localization in these patients have been identified, different pathoanatomical and pathophysiological substrates underlying these patterns have not been identified. However, a high incidence of posterior shoulder pain (75%) and upper back pain (66%) is striking.

METHODS

In a series of 326 thoracoscopic microdiscectomies for one or more symptomatic TDHs, we identified 10 patients whose symptoms had started after an MVC. We analyzed their clinical and radiological presentation, intraoperative findings, and postoperative outcome.

RESULTS

All patients (7 females, 3 males; age, 26-58 yr, including 4 with typical whiplash complaints) had reported substantial improvement of their complaints except for their upper back pain. Most hernias were small or medium sized (n = 8), at the apex of the kyphotic curvature (n = 6), and to some extent calcified (n = 7). One year postoperatively, results were excellent in 7, good in 2, and poor in 1.

CONCLUSION

Crippling upper back pain after MVCs may be caused by a (previously asymptomatic) thoracic disc herniation. Although the exact pathophysiological mechanism has not been elucidated, results after thoracoscopic microdiscectomy are quite encouraging.

Use of a radiopaque localizer grid to reduce radiation exposure

Background

Minimally invasive spine surgery requires placement of the skin incision at an ideal location in the patient's back by the surgeon. However, numerous fluoroscopic x-ray images are sometimes required to find the site of entry, thereby exposing patients and Operating Room personnel to additional radiation. To minimize this exposure, a radiopaque localizer grid was devised to increase planning efficiency and reduce radiation exposure.

Results

The radiopaque localizer grid was utilized to plan the point of entry for minimally invasive spine surgery. Use of the grid allowed the surgeon to accurately pinpoint the ideal entry point for the procedure with just one or two fluoroscopic X-ray images.

Conclusions

The reusable localizer grid is a simple and practical device that may be utilized to more efficiently plan an entry site on the skin, thus reducing radiation exposure. This device or a modified version may be utilized for any procedure involving the spine.

Thoracic disc herniation and acute myelopathy: clinical presentation, neuroimaging findings, surgical considerations, and outcome

OBJECT

Thoracic disc herniations (TDHs) may occasionally present with an acute myelopathy, defined as a variable degree of motor, sensory, and sphincter disturbances developing in less than 24 hours, and resulting in a Frankel Grade C or worse. Confronted with such a patient, the surgeon has to decide whether to perform an emergency operation and whether to use an anterior or posterior approach. The authors analyze their own experience and the pertinent literature, focusing on clinical presentation, imaging findings, surgical timing, technique, and outcome.

METHODS

Among 250 patients who underwent surgery for symptomatic TDH, 209 had at least 1 year of follow-up at the time of writing, including 8 patients who presented with an acute myelopathy. They were surgically treated using standard thoracoscopic microdiscectomy, careful blood pressure monitoring, and intravenous methylprednisolone. The authors analyzed pre- and postoperative neuroimaging, and Frankel scores preoperatively, at discharge, and 1 year postoperatively.

RESULTS

Although 5 patients had multiple TDHs, the symptomatic TDH was invariably situated between T9-10 and T11-12. Seven TDHs were giant, 6 were calcified, 6 were accompanied by myelomalacia, and 4 were accompanied by segmental stenosis. Although sudden dorsalgia was the initial symptom in 6, a precipitating event was noted in only 1. All patients had severe neurological deficits by the time they underwent surgery. Frankel grades improved from B to D in 2 patients, from C to E in 4, and from C to D and B to E in 1 patient each. All patients regained continence and ambulation. Transient complications were CSF leak (in 2 patients), and intraoperative blood loss greater than 1000 ml, reversible ischemic neurological deficit, and subileus (in 1 patient each).

CONCLUSIONS

Approximately 4% of TDHs present with an acute myelopathy. They are often situated between T9-10 and T11-12, large or giant, and even calcified. They almost invariably cause important cord compression (sometimes aggravated by an associated segmental stenosis) and myelomalacia. Their clinical presentation may be misleading, and diagnosis may be delayed until other causes (especially vascular) have been excluded and the clinical picture has become more complete. Interestingly, whereas a precipitating event or trauma is rarely present, dorsalgia frequently precedes profound myelopathy and may help to make an early diagnosis. Remarkable recovery is possible even with profound neurological deficit, a delay of several days, in the elderly, and in the presence of myelomalacia, provided the spinal cord is adequately decompressed and intraoperative hypotension is strictly avoided. Although alternative approaches more familiar to most neurosurgeons may be used, the anterior transthoracic approach has the advantage of reaching the TDH in front of the compromised spinal cord, avoiding any manipulation. In experienced hands, thoracoscopic microdiscectomy combines the advantage and versatility of an anterior approach with minimal postoperative discomfort. The authors conclude that TDH-related acute myelopathy may have a favorable outcome when managed correctly, and they strongly recommend that every single patient should undergo surgical treatment.

Intra-operative MRI-assisted spinal localization

BACKGROUND

Level localization in the thoracic spine can be problematic. We describe a new method that can be used in difficult cases, e.g., ones where lesions are mid-thoracic, small, or only visible on MRI.

METHODS

Intra-operatively, a midline incision was made and the thoracic spinous processes were exposed. A length of contrast-filled tubing was wound around the processes and the incision was temporarily closed and the patient was transferred to the radiology department for MRI under general anesthetic. Upon return to theatre, the cross sections of contrast-filled tubing and the lesion itself were visible on the MRI scan, allowing localization of the level.

FINDINGS

This method was accurate and minimized the extent of bone removal required for access.

CONCLUSIONS

This technique, while not appropriate in every case, is repeatable, and does not require specialized equipment or training. It is an extremely accurate method of localization for difficult cases.

Novel fluoroscopic technique for localization at cervicothoracic levels

STUDY DESIGN

To use a novel modified intraoperative fluoroscopic view for spinal level localization.

OBJECTIVE

To evaluate the safety and utility of the modified oblique fluoroscopic technique for intraoperative localization of distal cervical and proximal thoracic spinal levels.

SUMMARY OF BACKGROUND INFORMATION

Operative radiographic localization of the cervicothoracic spine using standard anterior-posterior and lateral views is made difficult by its anatomic relationship to the shoulder and upper chest, which produce radiographic shadowing obscuring the spine. Additional image degradation can be caused by muscular patients or those with a high body mass index. An oblique modification of the standard cross table lateral can be used to accurately identify pathologic levels at or across the cervicothoracic junction. This method distinctly demonstrates the bony lamina, which can then be used to count spinal levels. The unique feature of this technique is that the oblique angle removes the shoulder and the majority of the ribs from the active field of view, thereby producing a cleaner and more distinct image. When the gantry angle of the fluoroscope is parallel to the plane of the opposite lamina, it gives a type of "target sign" similar to the trans-pedicular image commonly used in pedicle screw placement. This radiographic sign can be easily identified and recognized across the cervicothoracic junction, even in those patients with a large body mass index or large musculature.

METHODS

Spinal level was determined intraoperatively through our oblique technique and confirmed in the same patient through standard views with retrograde counting. Postoperative imaging confirmed correct level surgery.

RESULTS

Correct spinal level identification was achieved in the distal cervical and proximal thoracic spine by implementation of our novel oblique fluoroscopy technique.

CONCLUSIONS

The modified oblique cross table fluoroscopy technique allows accurate operative localization across the cervicothoracic junction and well into the thoracic spine.

Two brothers with a symptomatic thoracic disc herniation at T11-T12: clinical report

BACKGROUND

In contrast to what is commonly believed, thoracic disc herniations are not rare lesions. Their etiopathogenesis is largely unknown, but may be linked to trauma, Scheuermann's disease or a degenerative back.

OBJECTIVE

We report two brothers with a symptomatic thoracic disc herniation at T11-T12 and address the possibility of a genetic factor as well as other factors in the etiopathogenesis of (symptomatic) thoracic disc herniations.

CLINICAL FEATURES

Both brothers were in their early thirties and had a physically demanding job, however, only the first one was a smoker and was diagnosed with Scheuermann's disease.

CONCLUSION

The etiology of thoracic disc herniations is likely multifactorial. Their occurrence in siblings may reflect some genetic predisposition or may be merely coincidental, given the high prevalence of thoracic disc herniations in asymptomatic individuals. Further research, including genetic studies, is warranted.

The position of the aorta relative to the spine: is it mobile or not?

STUDY DESIGN

This study analyzes the mobility of the aorta relative to the spine in patients with a herniated thoracic disc requiring surgical intervention.

OBJECTIVES

To determine the mobility of the aorta relative to the spine with the patient in prone and supine position.

SUMMARY OF BACKGROUND DATA

In anterior scoliosis surgery, safe screw placement is important and knowledge of the position of the aorta relative to the spine is crucial. To the authors' knowledge, there are no studies on the mobility of the aorta relative to the spine with the patient in different positions.

METHODS

All 50 patients before surgery had a computed tomography (CT) and/or magnetic resonance (MR) scans of the involved spinal segment in supine position, as well as a CT with intrathecal contrast in prone position. The aorta-vertebral angle and the aorta-vertebral distance were measured on as many levels as possible.

RESULTS

In supine position, the aorta is positioned left lateral to the vertebral body at midthoracic levels (T4-T8) and more anterior to the vertebral body at lower thoracic levels (T9-L2). In prone position, the aorta moves to a more anteromedial position relative to the vertebra, which is most significant at levels T4 to T8. The mediolateral aorta-vertebral distance according to Sevastik is shorter in prone position, whereas the anterior-posterior distance according to Sucato is larger, especially at levels T5 to T10.

CONCLUSIONS

We demonstrate a substantial difference in the position of the aorta relative to the spine in prone and in supine position, which is most markedly seen at levels T4 to T8. The aorta is positioned posterolateral to the spine in supine position and more anteromedial in prone position. Before performing anterior thoracolumbar spine surgery, we suggest to measure vertebral body width, as well as the position of the aorta in the prone and in the supine patient to decide if his approach is technically feasible, or if an alternative (contralateral) approach is preferable.