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World Neurosurgery Jan 2021Introduction of a posterior spacer for atlantoaxial joint distraction followed by posterior stabilization is a commonly performed procedure for irreducible atlantoaxial...
BACKGROUND
Introduction of a posterior spacer for atlantoaxial joint distraction followed by posterior stabilization is a commonly performed procedure for irreducible atlantoaxial dislocation. We present a unique case in which posterior distraction was associated with increased risk of injury to the vertebral artery (VA) owing to its anomalous course, and hence a novel anterior distraction technique was used.
CASE DESCRIPTION
A 45-year-old woman presented with severe neck pain for 1 month with gait imbalance and history of occipital headache for 1 year. Clinical examination revealed upper motor neuron-type findings. Hoffmann sign was positive bilaterally. Clinically, the patient had Nurick grade 4 cervical myelopathy. Magnetic resonance imaging showed basilar invagination along with Arnold-Chiari malformation and syrinx formation at C3-C4 vertebral levels. CT angiography revealed anomalous VAs directly overlying the atlanto-occipital joint. Owing to the anomalous route of the VA and unfavorable slope of facet joints, a 2-step anterior reduction followed by posterior stabilization surgery was planned. We achieved complete reduction using a 10-mm titanium cage inserted via a retropharyngeal approach. Following anterior reduction, instrumented in situ occipitocervical fusion was performed using a plate and screw construct. At 2-year follow-up, the patient is ambulating independently without gait imbalance and with successful radiologic fusion.
CONCLUSIONS
The craniovertebral junction has a unique pathoanatomy, and the course of the vertebral artery is variable. Appropriate investigations, including computed tomography angiography, with adequate surgical planning will provide a desirable long-term outcome. Our novel technique has the potential to add a new dimension to the management of irreducible atlantoaxial dislocation.
Topics: Arnold-Chiari Malformation; Atlanto-Occipital Joint; Bone Screws; Computed Tomography Angiography; Female; Headache; Humans; Internal Fixators; Joint Instability; Magnetic Resonance Imaging; Middle Aged; Neck Pain; Neurosurgical Procedures; Platybasia; Spinal Fusion; Treatment Outcome; Vertebral Artery
PubMed: 32891849
DOI: 10.1016/j.wneu.2020.08.220 -
Journal of Neurosurgery. Pediatrics Aug 2020Hajdu-Cheney syndrome (HCS) is a rare genetic disorder with autosomal dominant inheritance, although most cases result from de novo mutations. Progressive platybasia and...
Hajdu-Cheney syndrome (HCS) is a rare genetic disorder with autosomal dominant inheritance, although most cases result from de novo mutations. Progressive platybasia and basilar impression (BI) can potentiate obstructive hydrocephalus due to aqueductal stenosis. Limited literature exists on the surgical intervention for hydrocephalus in patients with this condition. The authors present (to their knowledge) the first case of obstructive hydrocephalus due to aqueductal stenosis from BI treated with an endoscopic third ventriculostomy in a patient with the complex anatomy of HCS.
PubMed: 32796142
DOI: 10.3171/2020.5.PEDS20218 -
European Spine Journal : Official... Nov 2020Retrospective study.
STUDY DESIGN
Retrospective study.
OBJECTIVE
Congenital craniovertebral (CV) anomalies include a wide variety of conditions involving basilar invagination (BI), atlantoaxial dislocation (AAD), bony congenital anomalies and Chiari malformation. The management of these disorders is more surgeon dependent rather than based on clear guidelines. This study aims to provide a step-by-step algorithmic approach to the management of congenital CV anomalies to achieve good CV alignment, neural recovery and long lasting stability.
MATERIALS
The study retrospectively analyses 71 patients of congenital CV anomalies treated by our algorithmic approach. Clinical assessment was done with the help of Nurick's grading pre- and post-operatively. Radiological outcome was assessed by plain radiographs, and computed tomographic scan was done at 12-month follow-up.
RESULTS
Mean age at presentation was 17.9 years (6-41 years). Mean Nurick score pre-operatively was 3.8 which was reduced to 1.3 at a mean follow-up of 13.6 months. Sixty-one patients had type I BI, 6 had type II BI, and 4 patients had os odontoideum. Most common symptom at presentation was weakness in limbs, neck pain and difficulty in walking. Patients of isolated AAD with os odontoideum required posterior atlantoaxial fixation and fusion only. Thirty-two patients of type I BI and 4 patients of type II BI required anterior release procedures prior to occipitocervical instrumentation. Bony fusion was achieved in 96% (68) cases with the help of autologous bone grafting. Three patients of occipitocervical fusion developed pseudoarthrosis.
CONCLUSION
Our retrospective analysis demonstrates that the algorithm is effective in ensuring long lasting results in all types congenital CV anomalies.
Topics: Atlanto-Axial Joint; Humans; Joint Dislocations; Platybasia; Retrospective Studies; Spinal Fusion
PubMed: 32676703
DOI: 10.1007/s00586-020-06522-4 -
Revista Da Associacao Medica Brasileira... Mar 2020Symptomatic Chiari Type I Malformation (CM) is treated with posterior fossa decompression with or without duroplasty. We have noticed some cases with concomitant severe...
BACKGROUND
Symptomatic Chiari Type I Malformation (CM) is treated with posterior fossa decompression with or without duroplasty. We have noticed some cases with concomitant severe cerebellar ataxia due to cerebellar atrophy. The aim of this study is to review the literature of CM associated with severe cerebellar atrophy and discuss its potential physiopathology.
METHODS
A systematic literature review in the Pubmed Database was performed using the following key-terms: "cerebellar atrophy Chiari", and "cerebellar degeneration Chiari". Articles reporting the presence of cerebellar degeneration/atrophy associated with CM were included.
RESULTS
We found only six studies directly discussing the association of cerebellar atrophy with CM, with a total of seven cases. We added one case of our own practice for additional discussion. Only speculative causes were described to justify cerebellar atrophy. The potential causes of cerebellar atrophy were diffuse cerebellar ischemia from chronic compression of small vessels (the most mentioned speculative cause), chronic raised intracranial pressure due to CSF block, chronic venous hypertension, and association with platybasia with ventral compression of the brainstem resulting in injury of the inferior olivary nuclei leading to mutual trophic effects in the cerebellum. Additionally, it is not impossible to rule out a degenerative cause for cerebellar atrophy without a causative reason.
CONCLUSIONS
Severe cerebellar atrophy is found in some patients with CM. Although chronic ischemia due to compression is the most presumed cause, other etiologies were proposed. The real reasons for cerebellar degeneration are not known. Further studies are necessary.
Topics: Arnold-Chiari Malformation; Atrophy; Cerebellar Diseases; Cerebellum; Decompression, Surgical; Female; Humans; Magnetic Resonance Imaging; Male
PubMed: 32520161
DOI: 10.1590/1806-9282.66.3.375 -
European Journal of Medical Genetics Aug 2020Primrose syndrome (OMIM 259050) is a rare disorder characterised by macrocephaly with developmental delay, a recognisable facial phenotype, altered glucose metabolism,...
Primrose syndrome (OMIM 259050) is a rare disorder characterised by macrocephaly with developmental delay, a recognisable facial phenotype, altered glucose metabolism, and other features such as sensorineural hearing loss, short stature, and calcification of the ear cartilage. It is caused by heterozygous variants in ZBTB20, a member of the POK family of transcription repressors. Recently, this gene was shown to have a role in skeletal development through its action on chondrocyte differentiation by repression of SOX9. We describe five unrelated patients with Primrose syndrome and distinct skeletal features including multiple Wormian bones, platybasia, bitemporal bossing, bathrocephaly, slender bones, epiphyseal and spondylar dysplasia. The radiological abnormalities of the skull and the epiphyseal dysplasia were the most consistent findings. This novel constellation of skeletal features expands the phenotypic spectrum of the disorder.
Topics: Abnormalities, Multiple; Adolescent; Bone and Bones; Calcinosis; Child; Child, Preschool; Ear Diseases; Female; Humans; Intellectual Disability; Male; Muscular Atrophy; Nerve Tissue Proteins; Phenotype; SOXB1 Transcription Factors; Transcription Factors; Young Adult
PubMed: 32473227
DOI: 10.1016/j.ejmg.2020.103967 -
BMC Neurology May 2020We propose two new concepts, the Filum Disease (FD) and the Neuro-cranio-vertebral syndrome (NCVS), that group together conditions thus far considered idiopathic, such...
BACKGROUND
We propose two new concepts, the Filum Disease (FD) and the Neuro-cranio-vertebral syndrome (NCVS), that group together conditions thus far considered idiopathic, such as Arnold-Chiari Syndrome Type I (ACSI), Idiopathic Syringomyelia (ISM), Idiopathic Scoliosis (IS), Basilar Impression (BI), Platybasia (PTB) Retroflexed Odontoid (RO) and Brainstem Kinking (BSK).
METHOD
We describe the symptomatology, the clinical course and the neurological signs of the new nosological entities as well as the changes visible on imaging studies in a series of 373 patients.
RESULTS
Our series included 72% women with a mean age of 33.66 years; 48% of the patients had an interval from onset to diagnosis longer than 10 years and 64% had a progressive clinical course. The commonest symptoms were: headache 84%, lumbosacral pain 72%, cervical pain 72%, balance alteration 72% and paresthesias 70%. The commonest neurological signs were: altered deep tendon reflexes in upper extremities 86%, altered deep tendon reflexes in lower extremities 82%, altered plantar reflexes 73%, decreased grip strength 70%, altered sensibility to temperature 69%, altered abdominal reflexes 68%, positive Mingazzini's test 66%, altered sensibility to touch 65% and deviation of the uvula and/or tongue 64%. The imaging features most often seen were: altered position of cerebellar tonsils 93%, low-lying Conus medullaris below the T12L1 disc 88%, idiopathic scoliosis 76%, multiple disc disease 72% and syringomyelic cavities 52%.
CONCLUSIONS
This is a paradigm shift that opens up new paths for research and broadens the range of therapeutics available to these patients.
Topics: Adolescent; Adult; Aged; Arnold-Chiari Malformation; Brain Stem; Child; Child, Preschool; Female; Headache; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Platybasia; Scoliosis; Syringomyelia; Young Adult
PubMed: 32393196
DOI: 10.1186/s12883-020-01743-y -
Surgical and Radiologic Anatomy : SRA Jul 2020There are many craniometric measurements that are used in evaluating craniovertebral junction (CVJ) pathologies such as basilar invagination, atlantoaxial dislocation...
INTRODUCTION
There are many craniometric measurements that are used in evaluating craniovertebral junction (CVJ) pathologies such as basilar invagination, atlantoaxial dislocation and platybasia. Therefore, it is important to determine the normal reference range of the craniometric measurements. This study aims to determine the morphometric reference values of the bony structures in the CVJ from cone-beam computed tomography (CBCT) images of a group of South Eastern Anatolian population.
MATERIALS AND METHODS
The CBCT images of 300 individuals were retrospectively evaluated. 14 parameters on midsagittal and 2 parameters on the coronal plane were studied. The data were statistically evaluated.
RESULTS
Measurement results were found as follows; the distances between odontoid process (OP) and McGregor line as 0.31 ± 3.22 mm, OP and Chamberlain line 1.06 ± 3.22 mm, OP and McRae line 5.30 ± 1.59 mm, OP and Fischgold digastric line 8.70 ± 4.12 mm, OP and Fischgold bimastoid line - 5.15 ± 4.86 mm, length of McRae line 35.58 ± 2.52 mm, atlantodental interval 1.28 ± 0.48 mm, posterior atlantodental interval 19.54 ± 2.24 mm, basion axial interval 4.01 ± 1.83 mm, basion dental interval 4.92 ± 1.77 mm, length of Modified Ranawat line 28.66 ± 2.38 mm, length of Redlund-Johnell line 35.11 ± 4.09 mm, clivus canal angle 157.62° ± 11.85°, Welcher basal angle 130.83° ± 6.29°, craniocervical tilt 126.98° ± 12.24° and Powers ratio as 0.72 ± 0.06.
CONCLUSION
In this study, the morphometric values were evaluated according to age and gender in individuals who did not have any radiologic anomalies. The normal reference ranges may be useful for researchers who are researching pathology in this region. It is recommended to conduct further studies with different populations to determine the normal reference range.
Topics: Adolescent; Adult; Aged; Anatomic Landmarks; Atlanto-Axial Joint; Atlanto-Occipital Joint; Cephalometry; Cone-Beam Computed Tomography; Female; Humans; Joint Dislocations; Male; Middle Aged; Occipital Bone; Odontoid Process; Platybasia; Reference Values; Retrospective Studies; Young Adult
PubMed: 32221664
DOI: 10.1007/s00276-020-02457-z -
World Neurosurgery Jun 2020Chiari malformation (CM) is defined as a herniation of cerebellar tonsils below the foramen magnum and is considered to be due to underdevelopment of posterior fossa... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Chiari malformation (CM) is defined as a herniation of cerebellar tonsils below the foramen magnum and is considered to be due to underdevelopment of posterior fossa (PF) bone components. There is overcrowding of neural structures, and normal cerebrospinal fluid circulation is frequently blocked. Although several publications exist of measurements of dimensions and volumes from bone components of PF in CM, there is no systematic review evaluating quantitatively these dimensions. The aim of this study was to evaluate PF dimensions and volumes in a meta-analysis.
METHODS
An electronic search using PubMed and Google Scholar was done. Study eligibility criteria were defined by the PICO strategy, which selected patients and interventions. Studies comparing PF dimensions between patients with CM and normal subjects were selected. A meta-analysis of pooled data was done using statistical software.
RESULTS
Data for pooled analysis were obtained from 12 studies. Data synthesis was based on small published sample sizes in the majority of studies. Key findings included smaller measurements of clivus, supraoccipital bone, and PF area dimensions in patients with CM compared with normal subjects. Brainstem and cerebellar length was not different between groups.
CONCLUSIONS
This review provides evidence of smaller measurements of clivus, supraoccipital bone, and PF area dimensions in patients with CM compared with normal subjects. An implication of the key findings is that surgical treatment of CMs should consider the smaller dimensions of PF in planning.
Topics: Arnold-Chiari Malformation; Case-Control Studies; Cephalometry; Cranial Fossa, Posterior; Humans; Magnetic Resonance Imaging; Occipital Bone; Organ Size; Platybasia; Reference Values; Tomography, X-Ray Computed
PubMed: 32156591
DOI: 10.1016/j.wneu.2020.02.182 -
World Neurosurgery May 2020Lumbar puncture is a common procedure that can be safely performed in most patients. Certain populations may have increased risk for complications following lumbar...
BACKGROUND
Lumbar puncture is a common procedure that can be safely performed in most patients. Certain populations may have increased risk for complications following lumbar puncture, but the significance of basilar invagination is often underappreciated.
CASE DESCRIPTION
A 45-year-old woman with basilar invagination received multiple lumbar punctures in the workup of acute meningitis. Preprocedural computed tomography was obtained. Following lumbar puncture, the patient developed locked-in syndrome. Magnetic resonance imaging obtained several days later demonstrated severe compression and infarction of the medulla and inferior cerebellum by the odontoid process and ectopic cerebellar tonsils. The patient was transferred but at this point, surgical decompression was not possible. She did not regain significant neurologic function.
CONCLUSIONS
Basilar invagination is a risk factor for devastating neurologic complications following lumbar puncture. Awareness of this complication and prompt recognition of its occurrence may prevent future morbidity of lumbar puncture in patients with basilar invagination.
Topics: Brain Stem Infarctions; Cerebellum; Female; Humans; Klippel-Feil Syndrome; Locked-In Syndrome; Magnetic Resonance Imaging; Medulla Oblongata; Meningitis, Pneumococcal; Middle Aged; Odontoid Process; Platybasia; Postoperative Complications; Spinal Fusion; Spinal Puncture; Streptococcus pneumoniae; Tomography, X-Ray Computed
PubMed: 32068170
DOI: 10.1016/j.wneu.2020.02.040 -
Clinical Radiology Jun 2020To describe the magnetic resonance imaging (MRI) findings of the cervical spine of patients with mucopolysaccharidosis type VI (MPS VI) and correlate them with clinical...
AIM
To describe the magnetic resonance imaging (MRI) findings of the cervical spine of patients with mucopolysaccharidosis type VI (MPS VI) and correlate them with clinical manifestations.
MATERIALS AND METHODS
This is a cross-sectional study involving 12 patients with MPS VI. A limited neurological examination was undertaken in each patient including Tinel's test, assessment of muscle tone, and the evaluation of deep tendon reflexes. Additionally, each patient underwent cervical spine MRI to evaluate platybasia, odontoid dysplasia, periodontoid soft-tissue thickening, spinal canal stenosis, myelopathy, basilar invagination, platyspondyly, and reduction of nasopharyngeal airway.
RESULTS
Nine patients were male (75%). The average age was 12.5 (±3.5 years). Tinel's test was negative in all patients. No muscle tone abnormalities were observed. Approximately 48% of the tested reflexes were considered abnormal, 10 of which (8.3%) were pathological occurring in five different patients (41.6%). At MRI, all patients showed periodontoid soft-tissue thickening and cervical spinal stenosis; six showed spinal cord compression and two showed myelopathy. Odontoid hypoplasia and basilar invagination were observed in nine patients. All patients with cervical stenosis on MRI had abnormal reflexes; however, only two of the six patients with evidence of cord compression on MRI had abnormal reflexes on clinical examination.
CONCLUSIONS
The present study of 12 patients with MPS VI demonstrated that a normal neurological examination cannot confidently exclude potential cord compression in patients with this condition. MRI may aid in the timely identification of cervical spine abnormalities, and potentially play a role in lessening morbidity and mortality in patients with MPS.
Topics: Cervical Vertebrae; Child; Cross-Sectional Studies; Female; Humans; Magnetic Resonance Imaging; Male; Mucopolysaccharidosis VI; Neurologic Examination; Spinal Cord Compression
PubMed: 32061396
DOI: 10.1016/j.crad.2020.01.007