China
Africa
Explore chapters and articles related to this topic
Understanding the Passenger
Published in Gowri Dorairajan, Management of Normal and High Risk Labour During Childbirth, 2022
The cranium or vault has two parietal bones on each side – one occipital bone posteriorly and two frontal bones in the front (Figure 3.1a). These bones are separated by sutures that are nothing but membranous space. Identifying the sutures during vaginal examination are key findings to determine the position of the head. There are four sutures: the coronal suture between the frontal bones and the two parietal bones, the sagittal suture between the two parietal bones, and the lambdoid suture that separates the occipital bone from the parietal bones. The frontal suture between the two frontal bones extends from the glabella to the anterior end of the bregma.
Abnormal Labour
Published in Sanjeewa Padumadasa, Malik Goonewardene, Obstetric Emergencies, 2021
Sanjeewa Padumadasa, Malik Goonewardene
Moulding is defined as the extent of overlapping of fetal skull bones which occurs as the fetal head adapts to the birth canal during labour. The parietal bones overlap the occipital bone, each other and in severe cases, the frontal bone. Moulding is graded from 0 to +3 according to severity (Figure 8.15).
Regional injuries and patterns of injury
Published in Jason Payne-James, Richard Jones, Simpson's Forensic Medicine, 2019
Jason Payne-James, Richard Jones
There are a variety of fracture types to the skull, often dependent on the nature of the impacting force (Figure 10.2). Blows to the top of the head commonly result in long, linear fractures that pass down the parietal bones and may, if the force was severe enough, pass inwards across the floor of the skull, usually just anterior to the petrous temporal bone in the middle cranial fossa. If the vault fractures extend through the skull base from both sides, they may meet in the midline, at the pituitary fossa, and produce a complete fracture across the skull base, referred to as a hinge fracture (Figure 10.3). This type of fracture indicates the application of very severe force and may be seen, for example, in traffic accidents or falls from high buildings.
Intracerebroventricular infusion of D-serine decreases nociceptive behaviors induced by electrical stimulation of the dura mater of rat
Published in Neurological Research, 2019
xiaolin Wang, zhe Yu, zi He, qiang Zhang, shengyuan Yu
Rats of groups A, B, and C were anesthetized with 10% chloral hydrate (4 ml/kg, i.p.) and then placed into a stereotactic frame. The scalp covering the dorsal surface of the skull was incised and the connective tissue and muscle were removed, leaving the parietal bone exposed. Two cranial windows (4 mm prior and 6 mm posterior to bregma on the midline suture, 1 mm in diameter) for electrical stimulation [10] and one (1.6 mm beyond the midline suture, 3.8 mm deep from the surface, 0.72 posterior to bregma, 1 mm in diameter) for infusion [11] were carefully drilled into the parietal bone and the skull was opened to expose the dura mater. A pair of stimulation electrodes was oriented and fixed onto the dural surface as described in our previous study [10]. All animals received prophylactic treatment by antibiotic injection and then were housed individually. The experimental procedures were approved by the Committee of Animal Use for Research and Education of the Laboratory Animals Center of Chinese PLA General Hospital (Beijing, China) and were consistent with the ethical guidelines recommended by the International Association for the Study of Pain for experimental pain in conscious animals (Zimmermann, 1983).
Creating a human head finite element model using a multi-block approach for predicting skull response and brain pressure
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
Zhihua Cai, Yun Xia, Zheng Bao, Haojie Mao
The contact force-time curves for parietal (vertical), frontal, and occipital impacts are shown in Figure 4a.The model-predicted maximum contact force was 13,797 N during parietal impacts (1.6% smaller than experimental measurement of 13,579 N), 13,609 N during frontal impact (0.07% bigger than experimental measurement of 13,600 N), and 10,017 N during occipital impact (experiment 10,009 N). The skull deformation-time curves are shown in Figure 4b. The maximum deformations were 7.58, 7.36, and 5.78 mm, respectively. The stress contours are exhibited in Figure 4c. A small number of elements failed in parietal bone area with a certain degree of linear fractures. There were no fractures in frontal impact. A fracture line appeared in occipital impact. The results obtained from the simulation were in good agreement with experiments.
Fluid–structure interaction analysis of cerebrospinal fluid with a comprehensive head model subject to a rapid acceleration and deceleration
Published in Brain Injury, 2018
Both the brain deformation and the initial fluid compressibility contribute to the formation of empty space depicted in Figure 6. Figure 6(b) shows that during the rapid acceleration phase, fluid particles flow backward, preventing the brain from impacting the occipital/parietal bone and creating an empty space between the anterior brain and frontal bone. During the rapid deceleration phase, fluid particles flow forward, preventing the brain from impacting the frontal bone and creating an empty space between the posterior brain and the occipital/parietal bones, Figure 6(c). The change from acceleration to deceleration causes the fluid particles to reverse direction. Because the fluid particles move faster than the brain, during the deceleration phase the fluid particles fill in the empty space created in the acceleration phase. This demonstrates the cushioning effect of CSF.