Anterior Thoracic Spinal Cord Herniation: Surgical Treatment and Postoperative Course. An Individual Participant Data Meta-Analysis of 246 Cases

The clinical evolution of patients with idiopathic spinal cord herniation: a case series

STUDY DESIGN

Retrospective case series of 48 patients.

OBJECTIVES

This study's primary objective was to provide a clinical description of a group of individuals with a working diagnosis of idiopathic spinal cord herniation (ISCH). The secondary objectives were to appreciate the natural history of these patients and describe their clinical evolution with conservative or surgical management.

SETTING

The study was carried out at l'Hôpital de l'Enfant-Jésus, CHU de Québec (Québec, Canada), a tertiary care university hospital.

METHODS

This case series study is based on routinely collected data. Forty-eight (48) cases were identified as having an ISCH on MR imaging, between 2009 and 2019. Their medical files have been searched retrospectively. Patient characteristics were described according to their asymptomatic or symptomatic status.

RESULTS

The mean age of patients at the time of diagnosis was 52.5 years. Most of the patients identified were asymptomatic (69%) and followed clinically. The main neurologic presentation for the symptomatic group was Brown-Séquard-like syndrome. 20% of the symptomatic patients were rapidly treated surgically after consultation with the neurosurgeon. The mean follow-up duration was 56 months for asymptomatic patients and 51 months for symptomatic patients. Most of our patients (41 out of 45) were considered stable or unchanged at follow-up. There was no neurological progression in all asymptomatic patients.

CONCLUSIONS

Our study shows that ISCH and its variants are not always symptomatic and may be a fortuitous finding. As the natural history may be non-progressive, it is probably appropriate to treat some cases expectantly.

Unveiling the Current Understanding of Idiopathic Spinal Cord Herniation: A Systematic Review

Background

Idiopathic spinal cord herniation (ISCH) is a rare condition that is characterized by ventral herniation of the spinal cord through a defect in the dura mater into the epidural space, with no identifiable cause. ISCH is frequently underdiagnosed, and the information available in case reports is limited. To provide an overview of the clinical manifestations and diagnosis of this condition, this study aims to conduct a review of reported cases of ISCH.

Methods

A literature review was carried out using seven databases. The search was conducted using the keywords "Idiopathic spinal cord herniation" OR "Idiopathic Ventral Spinal Cord Herniation" AND "Case report" OR "case series."

Results

A total of 92 relevant papers reporting 224 cases, besides the index case, were determined. Of the cases, 58.5% were females and the mean age was 50.7 (SD 13.2) years. Symptoms, diagnoses, and outcomes were similar between genders. The most common clinical signs included motor symptoms (82.6%), instability (61.3%), hypoesthesia (59.2%), and disturbance of thermal sensitivity (47.3%). Brown-Séquard syndrome was observed in 27.2% of the cases, and surgical treatment was employed in 89.7% of the cases.

Conclusions

ISCH is a pathology that is principally treated with surgical approach. This study provides valuable insights into the clinical manifestations and diagnosis of ISCH, which can aid in the early recognition and treatment of this rare condition.

Case report: A vertebral bone spur as an etiology for spinal cord herniation: case presentation, surgical technique, and review of the literature

Objective

The pathophysiology of idiopathic spinal cord herniation remains unknown. However, several different factors have been postulated, such as congenital causes (ventral dura mater duplication, preexisting pseudomeningocele, or other congenital dural defects), inflammation, remote spinal trauma, or thoracic disc herniation. Herein, the diagnosis and surgical treatment of a patient with spinal cord herniation caused by an intraspinal bone spur is presented along with a relevant literature review.

Case presentation

A 56-year-old male patient presented with a non-traumatic Brown-Sequard syndrome persisting for over 1 year. A magnetic resonance imaging of the spinal axis revealed a ventral spinal cord displacement in the level of T 6/7. A supplementary thin-sliced computed tomography of the spine revealed a bone spur at the same level. For neurosurgical intervention, T 6 and T 7 laminectomy was performed. The cranial and caudal end of the right paramedian ventral dural defect was visualized and enlarged. Following extradural spinal cord mobilization by denticulate ligament transection, the spinal cord was finally released. The spinal cord was rotated and the ventral closure of the dural defect was performed by continuous suture. The patient recovered from surgery without additional deficits. The patient's postoperative gait, sensory, and motor function deficits improved, and further neurological deterioration was prevented.

Conclusion

Since the first description of spinal cord herniation by Wortzman et al. in 1974, approximately 260 cases have been reported in the literature. In addition to other causes, intraspinal bone spur is a possible cause of spinal cord herniation.

Natural history and surgical outcomes of idiopathic spinal cord herniation

STUDY DESIGN

Retrospective multicenter study.

OBJECTIVES

Although surgery is frequently selected for the treatment of idiopathic spinal cord herniation (ISCH), its impact on functional outcomes has yet to be fully understood given the limited number of patients in previous studies. This study aims to evaluate the symptomatic history and surgical outcomes of ISCH.

SETTING

Three institutions in Japan.

METHODS

A total of 34 subjects with ISCH were retrospectively enrolled and followed up for at least 2 years. Demographic information, imaging findings, and clinical outcomes were collected. Functional status was assessed using the JOA score.

RESULTS

The types of neurologic deficit were monoparesis, Brown-Sequard, and paraparesis in 5, 17, and 12 cases, with their mean disease duration being 1.2, 4.2, and 5.8 years, respectively. Significant differences in disease duration were observed between the monoparesis and Brown-Sequard groups (p < 0.01) and between the monoparesis and paraparesis groups (p = 0.04). Surgery promoted significantly better recovery rates from baseline. Correlations were observed between age at surgery and recovery rate (p < 0.01) and between disease duration and recovery rate (p = 0.04). The mean recovery rates were 82.6%, 51.6%, and 29.1% in the monoparesis, Brown-Sequard, and paraparesis groups, respectively. The monoparesis group had a significantly higher recovery rate than did the Brown-Sequard (p = 0.045) and paraparesis groups (p < 0.01).

CONCLUSIONS

Longer disease duration was correlated with the progression of neurologic deficit. Older age, and worse preoperative neurologic status hindered postoperative functional recovery. These results highlight the need to consider surgical timing before neurologic symptoms deteriorate.

Analysis of Factors Contributing to the Occurrence of Systemic Toxicity in Patients with Hydrofluoric Acid Skin Exposure Injury: An Individual Participant Data Meta-Analysis of 125 Clinical Cases from 1979 to 2020

The purpose of this study is to analyze the factors contributing to the occurrence of systemic toxicity in patients injured after skin exposure to hydrofluoric acid (HFA) and to present guidelines for active treatment intervention based on this analysis. Data were acquired from EMBASE, PubMed, and Cochrane library for individual participant data (IPD) meta-analysis. Key searching terms included calcium gluconate (CAG), hydrofluoric acid, and case. This research consisted of case studies published between 1979 and 2020. Systemic toxicity was set as the main outcome. Data sets from 50 case studies (N = 125 participants) were analyzed. Multivariate binary logistic regression analyses of IPD found significant association effect of the total body surface area (TBSA) burned, indicating systemic toxicity [Regression coefficient estimate, 0.82; SE, 0.41; Odds ratio, 2.28; [95% confidence interval, 1.03-5.06], and p = 0.0424]. The optimal cutoff point (sensitivity; specificity) of the receiver operating characteristic curve of the total body surface area (TBSA) burned for contributing occurrence of systemic toxicity was 2.38(0.875; 0.959). IPD meta-analysis indicates that existing evidence supports the positive proportional association of the TBSA burned for systemic toxicity. If the TBSA burned (%) in patients exposed to hydrofluoric acid is greater than 2.38, early aggressive treatment intervention, including decontamination and various CAG application, should be recommended as the guideline.

Idiopathic Ventral Spinal Cord Hernia-A Single-Center Case Series of 11 Patients

BACKGROUND

Idiopathic spinal cord herniations (ISCH) are rare defects of the ventromedial or mediolateral dura mater with herniation of the spinal cord through the defect with approximately 350 described cases worldwide. Patients usually become symptomatic with motor or sensory neurological deficits and gait disturbances.

OBJECTIVE

To describe characteristic symptoms and clinical findings and to evaluate the postoperative course and outcomes of ISCH.

METHODS

We present a single-center data analysis of a case series of 11 consecutive patients who were diagnosed with ISCH and underwent surgery in our department between 2009 and 2021.

RESULTS

All herniations were located in the thoracic spine between T2 and T9. In most cases, gait ataxia and dysesthesia led to further workup and subsequently to the diagnosis of ISCH. A "far-enough" posterior-lateral surgical approach, hemilaminectomy or laminectomy with a transdural approach, was performed under intraoperative neurophysiological monitoring which was followed by adhesiolysis, repositioning of the spinal cord and sealing using a dura patch. After surgery, clinical symptoms improved in 9 of 11 patients (81.8%), while only 1 patient experienced deterioration of symptoms (9.1%) and 1 patient remained equal (9.1%). The median preoperative McCormick grade was 3 (±0.70), while the median postoperative grade was 2 (±0.98) ( P = .0047).

CONCLUSION

In our case series of ISCH, we found that in most patients, neurological deficits improved postoperatively. This indicates that surgery in ISCH should not be delayed in symptomatic patients.

Image-guided transthoracic transpedicular microdiscectomy for a giant thoracic disc herniation: patient series

BACKGROUND

This case series reports on five consecutive patients who underwent image-guided transpedicular transthoracic microdiscectomy. The authors retrospectively reviewed five patients who had undergone Stealth image-guided transpedicular transthoracic microdiscectomy between 2015 and 2021.

OBSERVATIONS

Image guidance with O-arm verified critical anatomical landmarks in the setting of large central calcified and/or soft tissue disc prolapse. This allowed limited rib head resection, pedicle removal, and corpectomy to give adequate access and not require interbody fusion. The authors performed a partial posterior corpectomy anterior to the affected disc prolapse and microsurgical delivery of the affected disc anteriorly into the corpectomy cave away from the thecal sac. Electronic and radiographic records were analyzed at their initial presentation and at follow-up. The median patient age was 51 years (range, 44-56 years), with 80% of the patients being males. Four of five patients had significant improvement of their presenting clinical symptoms. One patient had a complicated postoperative recovery with a pneumothorax and subsequent bilateral pneumonia requiring intensive care. Another patient developed delayed postoperative worsening of paraparesis.

LESSONS

The use of Stealth image guidance with O-arm for transthoracic microdiscectomy for complex calcified thoracic disc herniation is an effective operative technical adjunct to verify anatomical landmarks and limit the microsurgical procedure.

Long-term Risks of Persistent Ventral Spinal CSF Leaks in SIH: Superficial Siderosis and Bibrachial Amyotrophy

BACKGROUND AND OBJECTIVES

Superficial siderosis, bibrachial amyotrophy, and spinal cord herniation are unusual but serious long-term sequelae of persistent spontaneous spinal CSF leaks in patients with spontaneous intracranial hypotension (SIH), particularly ventral spinal CSF leaks. However, the risk of developing such sequelae has not been established in this population. We undertook this study to determine the risk of these serious complications of persistent ventral spinal CSF leaks.

METHODS

This cohort study was conducted using data from a prospectively maintained database of patients who meet the modified International Classification of Headache Disorders, 3rd edition criteria for SIH. The patient population consisted of a consecutive group of patients with SIH and persistent ventral spinal CSF leaks who were first seen within 1 year of onset of SIH symptoms and who had at least 1 year of follow-up.

RESULTS

Among 51 patients with SIH and a persistent ventral spinal CSF leak, superficial siderosis developed in 6 patients and bibrachial amyotrophy in 2 patients during 280 patient-years of follow-up. The probability of these complications increased from 0% at 48 months to 4.5% (95% confidence interval [CI] 1.0%-28.0%) at 56 months, 10.5% (95% CI 3.0%-36.4%) at 96 months, 32.7% (95% CI 15.0%-62.8%) at 144 months, and 57.9% (95% CI 30.2%-87.6%) at 192 months. None of the patients developed spinal cord herniation.

DISCUSSION

Among patients with SIH and a persistent ventral spinal CSF leak, the risk of developing serious long-term sequelae is considerable. This study shows that early treatment of a ventral spinal CSF leak offers a unique opportunity to prevent neurologic disability from superficial siderosis and bibrachial amyotrophy.

A unique case of pure lateral spinal cord herniation

BACKGROUND

Spinal cord herniation (SCH) remains a challenging diagnosis for neuroradiologists and may require treatment challenging for neurosurgeons. Most cord herniations are usually found at anterior thoracic levels.

CLINICAL PRESENTATION

A 28-year-old woman presented at our department with a 7-year history of progressive myelopathy. MR analysis showed a displacement of the spinal cord in a lateral thoracic dural defect. The herniated cord was released using a microscope and the patient significantly recovered 6 months after surgery.

CONCLUSION

We present a unique case of pure lateral SCH. In the light of reviewed literature and operative findings, the underlying pathophysiological mechanisms are discussed.

Genetic analysis of spinal dysraphism with a hamartomatous growth (appendix) of the spinal cord: a case series

Background

Spinal dysraphism with a hamartomatous growth (appendix) of the spinal cord is better known as herniated spinal cord. There are many arguments in favour of considering it a developmental defect. From this point of view, it is a type of neural tube disorder. Neural tube disorders can be caused by multiple factors, including a genetic factor. A common genetic defect in patients with a spinal dysraphism with a hamartomatous growth of the spinal cord is sought for.

Case presentation

In two patients with a symptomatic lesion and referred to an academic hospital a genetic analysis was performed after informed consent. Whole-exome analysis was performed.

: Whole-exome analysis did not result in identification of a clinically relevant genetic variant.

Conclusions

This the first study to investigate the genetic contribution to spinal dysraphism with a hamartomatous growth (appendix) of the spinal cord. We could not establish a genetic cause for this entity. This conclusion cannot be definitive due to the small sample size. However, the incidental occurrence, the lack of reports of inheritance of this disorder and the absence of contribution to syndromal disorders favours a defect of normal development of the spinal cord.

Ventral Thoracic Spinal Cord Herniation: Clinical Image and Video Illustration of Microsurgical Treatment

Idiopathic spinal cord herniation is a rare cause of progressive myelopathy that can result in severe disability. In the following report, an illustrative case and associated video in the surgical management of ventral thoracic spinal cord herniation is presented and discussed. Spinal cord herniation is most commonly observed in the thoracic spine and is characterized by ventral displacement of the spinal cord through a defect in the dura. Over time ventral herniation of the spinal cord can compromise its vascular perfusion, resulting in further ischemic injury. The etiology is unclear, but suspected to be either acquired or congenital. Multiple surgical techniques have been reported with the goal of detethering the cord and taking adjunctive measures in reducing the risk for re-herniation. Surgical management of thoracic spinal cord herniation carries great risks, although neurological outcomes are generally favorable with improvements reported in the majority of cases.