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Child's Nervous System : ChNS :... May 2020To analyze the varied presentation and management of atlas assimilation with associated radiographic abnormalities in children in the MRI era METHODS: Database analysis...
OBJECTIVE
To analyze the varied presentation and management of atlas assimilation with associated radiographic abnormalities in children in the MRI era METHODS: Database analysis of 313 children (less than 10 years) RESULTS: Atlas assimilation (AA) was associated with atlantoaxial dislocation in 12, abnormal skull base and Chiari I abnormality in 42, C2-C3 segmentation failure and instability and Chiari I abnormality in 74, and condylar hypoplasia and basilar invagination in 74. Proatlas segmentation failures were 54, atlantoaxial rotary dislocation in 26 with Goldenhar's syndrome, abnormal C1 atlas posterior arch causing dynamic compression of cord in 31 children. Vascular compromise was documented in 26 children. The study encompassed ages 6 months to 10 years. Cranial nerves commonly affected were glossopharyngeal, vagal, and hypoglossal nerves. Children below 2 years presented with torticollis, failure to thrive, difficulty swallowing, and motor and sensory deficits. Craniovertebral junction instability associated with AA was treated with custom-built craniocervical orthosis below 5 years. Closed reduction of instability or basilar invagination was attempted with neuromuscular blockade under anesthesia and traction above age 5 years. Successful reduction was treated with dorsal foramen magnum and atlas decompression with occiput-C2 dorsal fusion using rib grafts below the age of 5 years and instrumentation after that. Follow-up was 2 to 32 years. Neurological recovery was seen in nearly all patients.
CONCLUSIONS
Children with atlas assimilation and associated abnormalities may be symptomatic in early childhood. The treatment depends on the age and tailored to the abnormalities present. The long-term results have been successful.
Topics: Arnold-Chiari Malformation; Atlanto-Axial Joint; Cervical Atlas; Child; Child, Preschool; Decompression, Surgical; Foramen Magnum; Humans; Joint Dislocations; Platybasia; Spinal Fusion
PubMed: 31901967
DOI: 10.1007/s00381-019-04488-3 -
Clinical Neurology and Neurosurgery Aug 2021For reasons that are poorly understood and still undocumented, few patients of craniovertebral junction (CVJ) anomalies with instability/atlantoaxial dislocation (AAD)...
OBJECTIVE
For reasons that are poorly understood and still undocumented, few patients of craniovertebral junction (CVJ) anomalies with instability/atlantoaxial dislocation (AAD) in our practice have been seen to suffer unprecedented acute neurological deterioration with respiratory compromise about 48-72 h post-surgery. This has been specifically observed after an uneventful, stable clinical condition in the immediate postoperative period. This study attempts to elucidate the factors and outcomes related to such latent worsening.
PATIENTS AND METHODS
The 4-year surgical data of 268-patients with CVJ instability (AAD/basilar-invagination) who underwent C1-C2 fixation were retrospectively studied. The relevant factors of 17 patients who showed such deterioration were compared with that of the remaining in a multivariate model.
RESULTS
Seventeen patients had acute neurological worsening with respiratory arrest after a latent period. Ten improved at follow-up. Contrary to the general expectation, poor preoperative neurological score or severe dislocation that needed considerable manipulation did not influence such worsening. Dural injury in patients with associated Chiari malformation and vertebral arterial (VA) injury emerged as independent factors (p < 0.01) associated with this pattern of delayed neurological decline.
CONCLUSIONS
We report our management and outcomes of a unique subset of AAD with neurological worsening in the postoperative period after 48-72 h. Such a subgroup was not previously identified in literature. Dural lacerations in AAD with Chiari, and VA injury seem to predispose to such complications and should be prevented at best. Close observation, and caution regarding early extubation (<72 h) is recommended in this subset despite an apparently uneventful immediate postoperative neurological status.
Topics: Adolescent; Adult; Aged; Arnold-Chiari Malformation; Atlanto-Axial Joint; Atlanto-Occipital Joint; Child; Female; Humans; Joint Dislocations; Male; Middle Aged; Platybasia; Postoperative Complications; Spinal Fusion; Young Adult
PubMed: 34144465
DOI: 10.1016/j.clineuro.2021.106741 -
World Neurosurgery Feb 2021To evaluate the results of surgery for congenital craniovertebral junction (CVJ) anomalies with atlantoaxial dislocation (AAD)/basilar invagination (BI) and compare the...
OBJECTIVE
To evaluate the results of surgery for congenital craniovertebral junction (CVJ) anomalies with atlantoaxial dislocation (AAD)/basilar invagination (BI) and compare the results of transoral odontoidectomy and posterior fusion (TOO+PF) with only posterior fusion (PF) in patients with irreducible AAD/BI.
METHODS AND RESULTS
All 94 patients with congenital CVJ anomalies with AAD/BI operated on during the 3-year study period (June 2013-May 2016) were included. Of these patients, 55 had irreducible AAD/BI and the remaining 39 had reducible AAD/BI. TOO+PF was restricted to patients (34/94; 36.2%) with irreducible AAD/BI when reduction and realignment by intraoperative C1-C2 facet joint manipulation were considered technically difficult and risky. The remaining patients with irreducible AAD/BI and all the patients with reducible AAD/BI (60/94; 63.8%) were managed with only posterior fusion. Poor preoperative Nurick grade, preoperative dyspnea/lower cranial nerve deficits, and syringomyelia were associated with significantly higher incidence of postoperative pulmonary complications. Follow-up ≥3 months (final follow-up) was available for 87 patients. Good outcome (Nurick grade 0-3) at final follow-up was noted in 90% (45/50) of the patients with irreducible AAD/BI and 91.9% (34/37) of the patients with reducible AAD/BI. Preoperative poor Nurick grade (4-5) was the only factor associated with poor outcome. No significant difference in perioperative complications, outcome, and fusion was noted between patients who underwent TOO+PF or only PF for irreducible AAD/BI.
CONCLUSIONS
Many of the patients with congenital AAD/BI showed remarkable recovery after surgery. Preoperative poor Nurick grade (4-5) is associated with poor outcome. TOO+PF is a safe alternative treatment option for irreducible AAD/BI when only PF techniques are technically difficult/risky.
Topics: Adolescent; Adult; Aged; Atlanto-Axial Joint; Cervical Vertebrae; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Joint Dislocations; Male; Middle Aged; Odontoid Process; Platybasia; Preoperative Care; Retrospective Studies; Spinal Fusion; Treatment Outcome; Young Adult
PubMed: 33096283
DOI: 10.1016/j.wneu.2020.10.082 -
World Neurosurgery Dec 2019We evaluated the technical feasibility and potential advantages of transcranial insertion of an atlas screw for atlantoaxial fixation.
OBJECTIVE
We evaluated the technical feasibility and potential advantages of transcranial insertion of an atlas screw for atlantoaxial fixation.
METHODS
From January 2016 to August 2018, the transcranial technique for atlas screw insertion was used in 6 patients. Conventional lateral mass atlantoaxial fixation was not possible because of the presence of a complex craniovertebral junctional abnormality and difficulty in direct exposure of the facet of the atlas. In all cases, severe basilar invagination and assimilation of the atlas was present. Of the 6 patients, 3 were male and 3 were female. The age range was 12-41 years (average, 23 years). The surgical technique involved a small suboccipital craniotomy in line with the facet of the axis. Extradural elevation of the cerebellum exposed the region of the occipital condyle and fused atlas. The screw was directed medially and inferiorly into the facet of the atlas.
RESULTS
In all 6 patients, strong and successful atlantoaxial fixation was achieved. All patients showed clinical improvement after surgery. At an average follow-up period of 21 months, successful arthrodesis of atlantoaxial joint had been achieved in all 6 patients, with no complications.
CONCLUSIONS
Transcranial insertion of atlas screw can be used as a salvage procedure when the conventional method of screw insertion is not possible because of technical difficulties.
Topics: Adolescent; Adult; Atlanto-Axial Joint; Bone Screws; Child; Craniotomy; Feasibility Studies; Female; Humans; Male; Spinal Fusion; Vertebrobasilar Insufficiency; Young Adult
PubMed: 31476458
DOI: 10.1016/j.wneu.2019.08.152 -
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 -
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 -
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 -
European Spine Journal : Official... Jul 2023Malformations of the craniovertebral junction (CVJ) range from mild, asymptomatic conditions to severe forms of instability with basilar invagination. Rarely, there have...
PURPOSE
Malformations of the craniovertebral junction (CVJ) range from mild, asymptomatic conditions to severe forms of instability with basilar invagination. Rarely, there have been accounts of forms of so-called paramedian basilar invagination, with abnormal bone masses invading the lateral portion of the foramen magnum. All these entities have been comprehensively classified both from an anatomical and embryological standpoint.
METHODS
Here, we report a case of a unique CVJ malformation which is not included in any existing classification framework and could represent a novel pathologic entity. We also provide an overview of the pertinent literature.
RESULTS
The patient was a 14-year-old boy with a recent onset of spastic tetraparesis. Radiological studies documented a malformation of the atlas which invaginated through the foramen magnum, causing anterolateral medullary incarceration. Surgical treatment involved posterior decompression with resection of the abnormal bone and occipito-cervical fusion.
CONCLUSION
Our report enriches the panorama of CVJ malformations, showing how anatomical knowledge and embryological insights constitute the basis for the correct assessment and treatment of these complex entities.
Topics: Male; Humans; Adolescent; Foramen Magnum; Decompression, Surgical; Platybasia; Arnold-Chiari Malformation; Spinal Fusion
PubMed: 36527509
DOI: 10.1007/s00586-022-07500-8 -
BMC Musculoskeletal Disorders Dec 2020Transoral atlantoaxial reduction plate (TARP) fixation or occipitocervical fixation (OF) is an effective treatment for basilar invagination (BI) with irreducible...
BACKGROUND
Transoral atlantoaxial reduction plate (TARP) fixation or occipitocervical fixation (OF) is an effective treatment for basilar invagination (BI) with irreducible atlantoaxial dislocation (IAAD). But, all current clinical studies involved a single surgical procedure. The clinical effects of TARP and OF operation for BI with IAAD have yet to be compared. We therefore present this report to compare the treatment of TARP and OF procedure for BI with IAAD.
METHODS
Fifty-six patients with BI with IAAD who underwent TARP or OF operation from June 2011 to June 2017 were retrospectively analyzed. Among these, 35 patients underwent TARP operation (TARP group), and 21 patients underwent OF operation (OF group). We compared the difference of clinical, radiological, and surgical outcomes between the TARP and OF groups postoperatively.
RESULTS
Compared with OF group, the operative time and blood loss in TARP group were lower. There was no statistical difference in the atlantodental interval (ADI), clivus canal angle (CCA), cervicomedullary angle (CMA), distance between the top of the odontoid process and the Chamberlain line (CL) and Japanese Orthopaedic Association (JOA) score between the TARP and OF groups preoperatively, but the improvements of these parameters in the TARP group were superior to those in the OF group postoperatively. The fusion rates were higher in the TARP group than those in the OF group at the early stage postoperatively.
CONCLUSIONS
TARP and OF operations are effective surgical treatment for BI with IAAD, but the performance of reduction and decompression and earlier bone fusion rates of TARP procedure are superior to those of OF.
Topics: Atlanto-Axial Joint; Bone Plates; Decompression, Surgical; Humans; Joint Dislocations; Platybasia; Retrospective Studies; Spinal Fusion; Treatment Outcome
PubMed: 33292209
DOI: 10.1186/s12891-020-03838-6 -
European Journal of Radiology Nov 2020
Topics: Humans; Magnetic Resonance Imaging; Platybasia; Radiography; Radiology
PubMed: 32950798
DOI: 10.1016/j.ejrad.2020.109280