Finite element (FE) analysis has proven to be useful when studying the biomechanics of the cervical spine. Although many FE studies of the cervical spine have been published, they typically develop ...their models using commercial software, making the sharing of models between researchers difficult. They also often model only one part of the cervical spine. The goal of this study was to develop and evaluate three FE models of the adult cervical spine using open-source software and to freely provide these models to the scientific community. The models were created from computed tomography scans of 26-, 59-, and 64-year old female subjects. These models were evaluated against previously published experimental and FE data. Despite the fact that all three models were assigned identical material properties and boundary conditions, there was notable variation in their biomechanical behavior. It was therefore apparent that these differences were the result of morphological differences between the models.
The fibrous posterior atlanto-occipital membrane (PAOM) at the craniocervical junction is typically removed during decompression surgery for Chiari malformation type I (CM-I); however, its importance ...and ultrastructural architecture have not been investigated in children. We hypothesized that there are structural differences in the PAOM of patients with CM-I and those without.
In this prospective study, blinded pathological analysis was performed on PAOM specimens from children who had surgery for CM-I and children who had surgery for posterior fossa tumors (controls). Clinical and radiographic data were collected. Statistical analysis included comparisons between the CM-I and control cohorts and correlations with imaging measures.
A total of 35 children (mean age at surgery 10.7 years; 94.3% white) with viable specimens for evaluation were enrolled: 24 with CM-I and 11 controls. There were no statistical demographic differences between the two cohorts. Four children had a family history of CM-I and five had a syndromic condition. The cohorts had similar measurements of tonsillar descent, syringomyelia, basion to C2, and condylar-to-C2 vertical axis (all p>0.05). The clival-axial angle was lower in patients with CM-I (138.1 vs. 149.3 degrees, p = 0.016). Morphologically, the PAOM demonstrated statistically higher proportions of disorganized architecture in patients with CM-I (75.0% vs. 36.4%, p = 0.012). There were no differences in PAOM fat, elastin, or collagen percentages overall and no differences in imaging or ultrastructural findings between male and female patients. Posterior fossa volume was lower in children with CM-I (163,234 mm3 vs. 218,305 mm3, p<0.001), a difference that persisted after normalizing for patient height (129.9 vs. 160.9, p = 0.028).
In patients with CM-I, the PAOM demonstrates disorganized architecture compared with that of control patients. This likely represents an anatomic adaptation in the presence of CM-I rather than a pathologic contribution.
“Complex Chiari” malformations may be defined as cerebellar tonsil herniation combined with one or more of the following radiographic findings: brainstem herniation through the foramen magnum (Chiari ...1.5 malformation), medullary kink, retroflexed odontoid, abnormal clival-cervical angle, occipitalization of the atlas, basilar invagination, syringomyelia or scoliosis. Patients with “complex Chiari” malformation are different from those with typical Chiari 1 malformation in that their management strategy has a higher chance of including other operative interventions aside from a typical suboccipital decompression. These other operative procedures include odontoid resection and craniocervical fusion. This paper outlines specific scenarios where these other operative procedures must be considered and carried out.
Head trauma is a common presenting complaint among children requiring urgent medical attention, accounting for more than 600,000 emergency department (ED) visits annually, 4% to 30% of which identify ...skull fractures among the patient's injuries. Previous literature shows that children with basilar skull fractures (BSFs) are usually admitted for observation. We studied whether children with an isolated BSF have complications precluding them from safe discharge home from the ED.
We performed a retrospective review of ED patients aged 0 to 18 years given a simple BSF diagnosis (defined by nondisplaced fracture, with normal neurologic examination, Glasgow Coma Score of 15, no intracranial hemorrhage, no pneumocephalus) during a 10-year period to identify complications associated with their injury. Complications were defined as death, vascular injury, delayed intracranial hemorrhage, sinus thrombosis, or meningitis. We also considered hospital length of stay (LOS) longer than 24 hours or any return visit within 3 weeks of the original injury.
Of the 174 patients included in the analysis, there were no deaths, cases of meningitis, vascular injury, nor delayed bleeding events. Thirty (17.2%) patients required a hospital LOS longer than 24 hours and 9 (5.2%) returned to the hospital within 3 weeks of discharge. Of those with LOS longer than 24 hours, 22 (12.6%) patients needed subspecialty consultation or intravenous fluids, 3 (1.7%) had cerebrospinal fluid leak, and 2 (1.2%) had a concern for facial nerve abnormality. On the return visits, only 1 (0.6%) patient required readmission for intravenous fluids because of nausea and vomiting.
Our findings suggest that patients with uncomplicated BSFs can be safely discharged from the ED if the patient has reliable follow-up, is tolerating oral fluids, has no evidence of cerebrospinal fluid leak, and has been evaluated by appropriate subspecialists before discharge.
The complex Chiari, characterized by abnormal craniocervical bony anatomy in addition to Chiari tonsillar herniation, is a relatively recent addition to the concepts surrounding the Chiari ...literature. The primary findings of complex Chiari include craniocervical kyphosis and retroflexed odontoid, both of which can be described with radiographic measurements. This manuscript will outline the background literature regarding Chiari craniocervical morphometrics and supply an algorithm for the general management of complex Chiari patients.
Purpose
The purpose of this study was to assess the quality of articles utilizing large administrative databases to answer questions related to pediatric spinal neurosurgery by quantifying their ...adherence to standard reporting guidelines.
Methods
A systematic literature search was conducted with search terms including “pediatric” and “neurosurgery,” associated neurosurgical diagnoses, and the names of known databases. Study abstracts were reviewed to identify clinical studies involving pediatric populations, spine-related pathology or procedures, and large administrative databases. Included studies were graded using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria.
Results
A total of 28 papers of the initial 1496 identified met inclusion criteria. These papers involved 10 databases and had a mean study period of 11.46 ± 12.27 years. The subjects of these research papers were undergoing treatment of scoliosis (
n
= 5), spinal cord injury (
n
= 5), spinal cord tumors (
n
= 9), and spine surgery in general (
n
= 9). The mean STROBE score was 19.41 ± 2.02 (out of 22).
Conclusion
Large administrative databases are commonly used within pediatric spine-related neurosurgical research to cover a broad spectrum of research questions and study topics. The heterogeneity of research to this point encourages the continued use of large databases to better understand treatment and diagnostic trends, perioperative and long-term outcomes, and rare pathologies within pediatric spinal neurosurgery.
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