Segmental spinal dysgenesis: report of four cases and proposed management strategy

Atypical Variants of Spinal Dysraphism: A Case Series

The aim of this study is to present and discuss atypical instances of spina bifida (SB) within a Nigerian paediatric cohort, highlighting their distinctive clinicoradiological features. Additionally, a brief literature review is provided to contextualise these congenital anomalies. This series comprises eight rare cases of SB managed in a Nigerian neurosurgical facility. Additionally, a brief literature review is provided to contextualise these congenital anomalies. This case series comprises eight rare cases of SB managed in a Nigerian neurosurgical facility. Amongst these, four cases exhibited segmental spinal dysgenesis (SSD; one thoracolumbar, one lumbar, and two sacral). Each of these cases demonstrated diverse associated musculoskeletal, cutaneous, and perineal anomalies, accompanied by varying degrees of neurological dysfunction. Other cases included lipomyelomeningocele (LMMC), human tail (HT), membranous meningocele, and myeloschisis (MSS). Autonomic dysfunction was a common feature in all of the cases, whilst two of the patients presented with congenital kyphotic spinal deformity. Lower limb anomalies varied, including congenital talipes equinovarus deformity, pes planus, congenital calcaneovagus deformity, rocker bottom feet, clinodactyly, and tetrapolydactyly. Remarkably, none of the patients exhibited clinical features indicative of hydrocephalus. SSD, LMMC, HT, membranous meningocele, and MSS represent atypical forms of SB in the Nigerian paediatric population. Early neuroimaging of patients with suspected spinal dysraphism is crucial, as it may reveal a spectrum of diverse vertebral anomalies associated with this neurological condition within the African population.

A rare presentation of segmental spinal dysgenesis: Clinical and radiological findings

Segmental spinal dysgenesis is a rare and complex congenital condition affecting the dorso-lumbar spine, characterized by focal spinal cord dysgenesis and kypho-scoliotic deformity. It arises due to notochord malformation during embryogenesis. The case in question involves a 2-year-old female child. She presented to the outpatient department of our hospital with a history of inability to walk and increased frequency of micturition. The patient's mother had no antenatal visits. Upon examination, the patient was found to have a scoliotic deformity. Magnetic resonance imaging (MRI) of the spine revealed an absence of the spinal cord and spinal nerves from the T5 to L2 levels. A relatively thick spinal cord was visible from the L2 to L4 level. There was a complete absence of the spinal canal at the D10 and D11 levels, along with dorsal levoscoliosis. Segmental anomalies of the vertebrae were also noted in the dorsal spine. Additionally, imaging showed features of neurogenic bladder and mild left hydroureteronephrosis. The child underwent rehabilitation and surgical correction of the scoliosis.

Segmental spinal dysgenesis: insights from three consecutive cases and a review of the literature

OBJECTIVE

Segmental spinal dysgenesis (SSD) is a rare congenital spinal abnormality affecting the thoracic and lumbar region of the spine, as well as the spinal cord of neonates and infants. The purpose of the study was to analyze our institution's surgical case series to provide insights into our best practices to contribute to SSD management principles, while conducting a comprehensive literature review.

METHODS

Following institutional review board approval, a retrospective review of SSD surgical cases was examined to observe clinical findings, radiographic findings, management, surgical intervention, and outcomes. Keywords in the comprehensive literature review included SSD, congenital spinal dysgenesis, congenital spinal stenosis, spinal aplasia, and surgery.

RESULTS

Three cases underwent successful surgical management with either improvement or maintenance of neurological baseline. Patients were diagnosed at an average age of 2.7 months, while surgical intervention averaged at 40.3 months with fecal incontinence, neurogenic bladders, spinal cord compression, clubfoot, and concerns for worsening spinal deformity as surgical indicators. The average time for follow-up was 33.7 months and no complications were reported.

CONCLUSIONS

Operative management for SSD is a clinically complex decision that requires multidisciplinary input and care. Patients should be observed at neurological baseline and receive intervention at the appropriate time to allow sufficient growth for functioning without permitting drastic disease progression. Consideration of patient size and spinal instrumentation are significant towards surgical success.

Cervicothoracic dislocation due to congenital and bone-dysplasia-related vertebral malformations

PURPOSE

To evaluate the approaches to treatment of congenital and bone-dysplasia-related pediatric cervicothoracic dislocations and define the optimal treatment method.

METHODS

The publications available in PubMed and Google Scholar data bases were selected following such criteria as the disease in question, pediatric age, the treatment description, and follow-up results. The paper also includes the descriptions of our own six cases of the cervicothoracic dislocations detected in children with different vertebral malformations.

RESULTS

Only eight patients meeting the abovementioned selection criteria were found in the publications: three of them had the Klippel-Feil syndrome (KFS), two had one-level vertebral anomaly, one had neurofibromatosis (NF type 1), one had the Larsen syndrome, and one had a variation of VACTERL association. Their treatment was long term, multi stage, and complicated. Among six our own cases, four patients also had KFS, one had a variation of VACTERL association, and one had NF type 1. All the patients suffered from preoperative neurological disorders. Posterior instrumental fixation with posterior vertebral body resection was performed in four cases and one patient underwent a combined surgery. The parents of one of the patients refused the operation, so he was observed while receiving bracing treatment. Since the treatment was long term and complicated by reoperations, the average follow-up period comprised 5 years.

CONCLUSION

Congenital cervicothoracic dislocations are an extremely rare pathology that manifests itself in early age and requires an early surgical treatment. Failure to provide the treatment leads to the patient's disability. The surgical tactics for such patients is determined individually, but the published data and our own experience demonstrate that early multi-stage combined treatment has been the best option available so far. The cervicothoracic dislocations due to NF 1 manifest later and have a more favorable forecast.

Severe type of segmental spinal dysgenesis with complete disconnection of the spinal cord and vertebra associated with open neural tube defect

Background

Severe type of segmental spinal dysgenesis (SSD) is a rare and complex anomaly in which the spinal cord completely disconnects at the portion of the spinal dysgenesis. Although closed spinal dysraphisms have been associated with SSD, to the best of our knowledge, the association between open neural tube defect (ONTD) and SSD is significantly rare, with only one case being reported to date.

Case Description

We report a case of an infant with severe SSD and a disconnected spinal cord and spinal column at the thoracolumbar junction associated with myelomeningocele (MMC) in the lumbosacral region. The patient presented severe neurological deficits in the legs and impaired bowel function. The spinal column of L1-L3 was absent. The lower spinal segment consisted of neural placode at the L5-S1 level and no connecting structure between the upper and lower spinal cords. A repair surgery for MMC, including cord untethering and dura plasty, was performed. Histopathological findings revealed a neural placode consisting of a neuroglial tissue and leptomeninges.

Conclusion

The management of severe SSD during the perinatal period is more challenging when it is associated with ONTD. We report detailed neuroradiological, intraoperative, and histological findings of such a case and discuss the embryopathogenesis of the associated ONTD and the treatment strategies.

Congenital cervicothoracic dissociation: report of two cases

PURPOSE

Congenital cervicothoracic dissociation (CCTD) of the spine is a rare condition while having major impacts on stability and neurological function. Surgical treatment includes decompression and instrumented fusion. Only few cases of CCTD have been reported in children. This report intends to demonstrate the complexity of this condition and its surgical management options based on two cases.

METHODS

Retrospective illustration of two cases with CCTD treated with instrumented occipito-thoracic fusion. Timing and options of surgical management are discussed.

RESULTS

Two patients aged 9 and 12 were treated. Patient 1 presented with asymmetric chronic weakness of the upper extremity and unstable neurogenic bladder. Imaging showed a CCTD with severe distortion of the posterior facets and a dysplastic spinal cord. Patient 2 presented with mild spasticity and unilateral weakness of the upper extremity. A low energy trauma resulted in tetraplegia by increasing the amount of antero-posterior displacement. Both patients were treated with Halo vest application, followed by posterior decompression, and instrumented occipito-thoracic fusion. Additional upfront Halo traction was applied in patient 2 for distraction and sagittal alignment improvement. The last follow-up confirmed solid fusion and minor residual neurological impairment in both patients at 5, and 6 years, respectively.

CONCLUSION

CCTD is a rare congenital condition, which can be successfully managed by posterior instrumented fusion. A sudden cervicothoracic displacement with neurological deterioration may respond to careful Halo traction with preoperative sagittal alignment correction. Timing of surgery depends on the actual instability in neurologically stable patients.

Imaging of Congenital Spine Malformations

Congenital malformations of the spine and spinal cord are a large and diverse group of diagnoses, which are often broadly referred to as spinal dysraphisms (SDs). Derived from the Greek words dys (bad) and raphe (suture), the term dysraphism describes missteps in the process of forming a midline seam during the zipper-like fusion of the neural folds in primary neurulation. As such, the term "spinal dysraphism" is a designation that should technically be reserved for malformations resulting from aberrations in primary neurulation. In medical practice, however, it is a catch-all designation regularly used to describe any of the numerous abnormalities demonstrating incomplete midline closure of mesenchymal, osseous, and nervous tissue, occurring at any point during embryologic development. For the sake of clarity and completeness, this article will also include that breadth in the discussion of congenital abnormalities of the spine.

Junctional Neurulation : A Junction between Primary and Secondary Neural Tubes

Recent case reports of junctional neural tube defect (JNTD) which is a peculiar type of spinal anomaly showing the functional disconnection of the primary and secondary neural tubes has risen interest in the process of junctional neurulation (the connection between the two neural tubes) during development. This article summarizes the clinical features of the JNTD and reviews the literature on the basic research on junctional neurulation.

Surgical treatment of segmental spinal dysgenesis: a report of 19 cases

STUDY DESIGN

Retrospective review.

OBJECTIVE

To describe clinical presentation, surgical management, long-term results, and complications in patients with segmental spinal dysgenesis (SSD). In addition, we sought to emphasize early surgery for this complex congenital abnormality. SSD is a rare congenital malformation characterized by focal stenosis, spinal subluxation, kyphosis, and absence of the nerve roots. Neurologic function ranges from normal to complete paraplegia. Progression of the deformity and neurologic deterioration is the rule.

METHODS

An independent spinal surgeon reviewed the complete records of 19 patients with SSD, between 1998 and 2015 at a single institution. Mean follow-up was 10 years and 6 months (2-14 years).

RESULTS

We evaluated 11 males and 8 females, with a mean age of 2 years and 9 months (5 months-15 years). The dysgenetic segment involved an average of 2.9 vertebrae (1-5); the upper thoracic region was most commonly involved in ten cases. Fifteen patients had severe spinal stenosis. 14 patients presented neurological deficits and 15 patients had associated organ and musculoskeletal anomalies.Twenty-seven surgeries were performed, a mean of 1.76 procedures (1-5) to obtain solid fusion. Neurologic function improved in four, deteriorated in three, and remained unchanged in 12 patients Seven complications were recorded.

CONCLUSION

We strongly recommend decompression and fusion as soon as possible to preserve or prevent neurologic deterioration. Although challenging, it was possible to achieve a solid instrumented fusion in all cases; however, a high rate of patients may deteriorate or not recover neurological status after surgery.

LEVEL OF EVIDENCE

Level IV evidence.

Segmental spinal dysgenesis with open spinal dysraphism and Chiari II features, case report

Segmental spinal dysgenesis (SSD) is a complex spinal anomaly characterized by localized dysgenesis of the lumbar or thoracolumbar spine, and severe congenital kyphosis or kyphoscoliosis. We describe a newborn who presented with severe congenital paraplegia and a lumbar mass. Magnetic resonance imaging confirmed SSD type II associated with open spinal dysraphism and intracranial Chiari II features; this association has not been reported. The association modifies the disease management and outcome. The previous classification of SSD could be revisited based on our case.

Do junctional neural tube defect and segmental spinal dysgenesis have the same pathoembryological background?

INTRODUCTION

Junctional neural tube defect (JNTD) is a recently introduced form of congenital spinal dysraphism that is characterized by functional disconnection between the primary and secondary neural tubes. The upper and lower cords appeared to be connected by a non-functioning band-like structure. JNTD is suspected to arise from a developmental error not corresponding to either primary or secondary neurulation, but rather between the two neurulation processes. On the other hand, segmental spinal dysgenesis (SSD) is an older entity of spinal anomalies in which a segment of the spine and spinal cord does not develop properly. The anomaly had been noted for the bony abnormality, as it is the most prominent feature. Based on the recent encounter of two cases resembling both entities, we sought the possibility that the two diseases may have the same pathoembryogenesis.

METHODS AND RESULTS

Based on the impression that the two entities share important features, we compared the details of the two anomalies. First, our two recently encountered cases of JNTD were described. Second, previous reports of SSD were comprehensively reviewed. The two cases had the essential anomaly of the neural structures satisfying the definition of JNTD, as well as the elaborate spinal deformity as seen in SSD. In the previous literature on SSD, it was recognized that in addition to the bone anomaly, disconnected spinal cord was present. Hence, the two entities seem to have many similar clinical and neuroimaging features. The dysgenic spinal level is similar, and the disconnection between the primary and secondary neural tubes is found in the two diseases. The two neural tubes are connected by a band-like structure, with severe stenosis of the spinal canal at the level of the band. Both entities show segmental anomalies of the vertebrae in the thoracolumbar region, especially in the posterior element. Although the extent of shared features seems high, the previously suggested hypothetical pathoembryogenesis of SSD did not involve the process of junctional neurulation. We suggest that SSD shares the same origin as JNTD, and the bony abnormality may be a secondary phenomenon to the core error during neural tube development.

CONCLUSIONS

We propose that JNTD and SSD may be the same entity, originating from an error during junctional neurulation. As there is controversy regarding the treatment strategy for both entities, unified accumulation of clinical experience and analysis may help improve the management of patients.

Segmental Spinal Dysgenesis-"Redefined"

STUDY DESIGN

Retrospective single institutional observational study.

PURPOSE

Segmental spinal dysgenesis (SSD), a complex spinal dysraphic state caused by notochord malformation disorders, is named after its morphological presentation where a spine segment is dysgenetic, malformed or absent. This study's objective was to examine and reassess SSD imaging findings and correlate them with an embryological explanation.

OVERVIEW OF LITERATURE

Scott and his colleagues defined SSD as segmental agenesis or dysgenesis of the lumbar or thoracolumbar vertebrae and underlying spinal cord. Tortori-Donati and his colleagues defined it as a morphologic continuum ranging from hypoplasia to an absent spinal cord segment.

METHODS

Fifteen children, whose imaging findings and clinical features were consistent with SSD, were included in the study. Magnetic resonance imaging (MRI) was performed per institutional spine protocol.

RESULTS

Five children (33.3%) presented with a high-ending bulbous cord with no caudal segment, six (40%) presented with a dorsal or lumbar segmental dysgenetic cord with a low-lying, bulky caudal cord but without significant spinal canal narrowing, and four (26.6%) presented with segmental caudal dysgenesis with severe kyphoscoliosis, gibbus deformity, and spinal canal narrowing with a normal distal segment (normal or low-lying).

CONCLUSIONS

SSD is a complex spinal anomaly in children requiring clinical-radiological assessment followed by multidisciplinary management based on the extent and severity of the dysgenetic cord and the type of SSD. MRI plays a crucial role in both diagnosing and classifying SSD prior to surgical treatment to prevent further impairment.

Surgical Treatment of Thoracolumbar Segmental Spinal Dysgenesis: Optimal Type of Fusion

OBJECTIVES

We sought to evaluate long-term results of surgical treatment of thoracolumbar segmental spinal dysgenesis (SSD).

METHODS

We analyzed 8 patients with thoracolumbar SSD treated in our institution. Each case was evaluated for specific clinical and radiologic criteria and types and outcomes of treatment.

RESULT

The average age of primary surgery was 3.4 years (median 3.4 years, range 1.7-7 years). The average correction of kyphosis was 49.3° (mean 45°, from 25°-75°) and scoliosis 10.6° (mean 10°, from 0°-25°). Average follow-up time was 3.2 years (mean 2.6 years, from 1.8-5.6 years). Neurologic improvement was also achieved in all patients. The Japanese Orthopaedic Association scale score (Benzel's modification) was increased by 2.5 points on average (mean 2.5 points, from 2-5 points). One patient had complications: pseudarthrosis and rod fracture followed by refusion.

CONCLUSIONS

Our treatment strategy provides favorable deformity correction and neurologic improvement. It is limited by immature vertebral structures in newborns and infants, who should be carefully monitored from birth with braces until they reach the age when a fixing tool can be used.

Segmental spinal dysgenesis: a report of early surgical intervention and outcome in a 14-month-old child

Segmental spinal dysgenesis is a rare spinal deformity that is the result of failure of formation resulting in some cases spondyloptosis and neurological dysfunction usually at the thoracolumbar junction. There is little known concerning surgical intervention and timing in these patients. The goal of this case report is to present a case involving 14 months old diagnosed with segmental spinal dysgenesis with stenosis at the thoracolumbar junction soon after birth, treated with definitive posterior spinal fusion and subsequent follow-up.