RESUMO
SUMMARY: A comparative study of the skull morphology was conducted using 270 prenatal and 750 postnatal skull samples from three breeds of sheep in Nigeria namely, Balami, Uda and Yankasa. A unique bone peculiar to the Yankasa breeds of sheep was found consistently at the centre of the anterior fontanelle in the young (day-old to 1 year). At two years of age and above, the bone was fused and disappeared completely. This brings the total numbers of the neurocranium bones of the skull in the Yankasa breeds to 8, as against the 7 bones documented in the ovine species. Due to the fact that this bone has not been described in the literature, we venture to name it the anterio-fontanelle bone (of Atabo).
Se realizó un estudio comparativo de la morfología del cráneo utilizando 270 muestras de cráneos prenatales y 750 postnatales de tres razas de ovejas en Nigeria, Balami, Uda y Yankasa. Un hueso único peculiar de las razas de ovejas Yankasa se encontró consistentemente en el centro de la fontanela anterior en las crías (de un día a 1 año). A los dos años de edad o más, el hueso se fusionó y desapareció por completo. Esto eleva el número total de huesos del neurocráneo en el cráneo en las razas Yankasa a 8, frente a los 7 huesos documentados en la especie ovina. Debido a que este hueso no ha sido descrito en la literatura, nos aventuramos a denominarlo hueso antero-fontanela (de Atabo).
Assuntos
Animais , Carneiro Doméstico/anatomia & histologia , Fontanelas Cranianas/anatomia & histologia , Crânio/anatomia & histologiaRESUMO
Background and Objective: To simulate infant skull trauma after low height falls when variable degrees of ossification of the sutures are present. Methods: A finite elements model of a four-week-old infant skull was developed for simulating low height impact from 30 cm and 50 cm falls. Two impacts were simulated: An occipito-parietal impact on the lambdoid suture and a lateral impact on the right parietal and six cases were considered: unossified and fully ossified sutures, and sagittal, metopic, right lambdoid and right coronal craniosynostosis. Results: 26 simulations were performed. Results showed a marked increase in strain magnitudes in skulls with unossified sutures and fontanels. Higher deformations and lower Von Mises stress in the brain were found in occipital impacts. Fully ossified skulls showed less overall deformation and lower Von Mises stress in the brain. Results suggest that neonate skull impact when falling backward has a higher probability of resulting in permanent damage. Conclusion: This work shows an initial approximation to the mechanisms underlying TBI in neonates when exposed to low height falls common in household environments, and could be used as a starting point in the design and development of cranial orthoses and protective devices for preventing or mitigating TBI.
Assuntos
Fontanelas Cranianas/lesões , Suturas Cranianas/lesões , Modelos Anatômicos , Osso Occipital/lesões , Osso Parietal/lesões , Acidentes por Quedas/prevenção & controle , Fenômenos Biomecânicos , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/prevenção & controle , Fontanelas Cranianas/anatomia & histologia , Suturas Cranianas/anatomia & histologia , Traumatismos Craniocerebrais/patologia , Traumatismos Craniocerebrais/prevenção & controle , Craniossinostoses/patologia , Análise de Elementos Finitos , Humanos , Recém-Nascido , Osso Occipital/anatomia & histologia , Osso Parietal/anatomia & histologiaRESUMO
OBJECTIVE: To make a description of the anatomy of fontanelles and to update what is currently known about their applications. METHOD: 7 cadaveric heads, 2 dry skulls and 2 frontal bones of foetus were used, and 48 anterior fontanelles from paediatric patients with or without associated pathology were examined. Surgical cases and neurosonography were also used. All the structures were measured and subsequently analysed. RESULTS: The size, structure and limits of the fontanelles were evidenced in the cadaveric head and skulls, as well as the evaluation of paediatric patients and the size of their fontanelles in different pathologies. CONCLUSION: Owing to their anatomical characteristics, fontanelles are a true window to the inside of the skull, which determines their multiple clinical and surgical applications.
Assuntos
Fontanelas Cranianas/anatomia & histologia , Cadáver , Criança , Feminino , Feto/anatomia & histologia , Osso Frontal/anatomia & histologia , Idade Gestacional , Humanos , GravidezRESUMO
To analyze cranial growth and size of anterior fontanel during the first year of life, we undertook a cohort study with a sample of 33 infants assessed at birth and reexamined at 1, 2, 3, 4, 5, 6, 9, and 12 months. Examination included assessment of head circumference, anterior fontanel size, anteroposterior distance, biauricular distance, and cephalic index. All infants were neurologically normal. Mean size of the anterior fontanel at birth was 1.77 cm(2) and, in disagreement with literature data, fontanel size increased up to 2 months of age; fontanel was closed at 1 year for 27.3% of infants. Significant differences in cranial anthropometry were not found in relation to method of delivery (vaginal or cesarean section), gender and gestational age. Our results indicate the need to reevaluate anthropometric examination data and to establish patterns of normality, particularly for miscegenated populations that have not been widely investigated.