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This chapter reviews the normal anatomy, fractures and challenges of the upper extremity frequently encountered in child abuse imaging. Specifically, fracture types of the humerus, the elbow and the forearm are examined with attention to imaging techniques and protocols, particularly radiography and ultrasound.
Facial and orbital trauma are frequently seen in cases of child abuse, with certain patterns, such as specific types of retinal haemorrhage, being highly indicative of abusive head trauma. These injuries can be subtle on imaging and often lack a clear history. While some abusive injuries may resemble accidental ones, particular injury patterns or combinations of injuries, alongside additional clinical findings, raise concerns for abuse. Radiologists play a critical role in diagnosing these injuries by obtaining a thorough history and utilizing advanced imaging techniques like MRI and CT with three-dimensional reconstructions, which provide detailed views of soft tissue and bone. Recognizing subtle signs of trauma and correlating them with the clinical context is essential for accurate diagnosis and the child’s protection. Early detection and precise diagnosis by the radiologist enable the multidisciplinary team to intervene appropriately, ensuring the safety and well-being of vulnerable children.
This chapter reviews the imaging approach in suspected child physical abuse, including differing presentations of child physical abuse as well as recommendations for screening children at risk. Imaging strategy of the skeleton, including radiography, chest CT, ultrasound, whole-body MR and radionuclide bone imaging is reviewed.
Osteogenesis imperfecta (OI), colloquially known as “brittle bone disease,” must be routinely considered in all children presenting with recurrent or unexplained fractures. Proper medical work-up includes careful consideration of the history of present illness, review of growth patterns including length/ height, past medical history, family history, physical examination, radiographic and laboratory findings. For decades, OI was described as four major types categorized largely based on clinical features, but in the modern era of genomics, there is more expanded molecular diagnosis and nomenclature. In general, OI can be clinically categorized into mild, moderate, and severe forms. In unexplained fractures in infants, mild forms of OI present an important differential diagnosis to child abuse; more moderate and severe types are usually readily diagnosed based on clinical and radiographical presentation. There is a role for judicious use of genetic testing in cases where OI is a possibility. Ehlers-Danlos syndrome has been purported to cause fractures and mimic child abuse in infants and young children, but this is a flawed explanation largely manufactured for courtroom purposes. By understanding the natural history of OI versus other connective tissue disorders, and by adopting appropriate clinical strategies and evidence-based practices, multidisciplinary clinical teams enhance diagnostic accuracy and improve clinical outcomes for children in our care.
Given there is no prospective research evidence on the association between ultra-processed food intake (UPF) and human bone health, this study aimed to analyze the associations of UPF intake with bone mineral density (BMD) and risk of fractures using data from 163855 participants in the UK Biobank. Multiple linear regression assessed BMD, and Cox regression models estimated fracture risk. Restricted cubic splines were used to evaluate non-linearity. Participants’ average age was 56.0 years, with 1097 hip fractures and 7889 all fractures recorded over 12.0 years of follow-up. Complex inverted U-shaped associations between UPF intake and BMD were found at the femur trochanter. Compared with the lowest UPF intake, the highest UPF intake was linked to a reduction in BMD at the femoral neck (β [SE] = –0.0061 [0.0024], P < .05), femur trochanter (β [SE] = –0.0083 [0.0024], P < .001), lumbar spine (β [SE] = –0.0114 [0.0036], P < .01), and total body (β [SE] = –0.0095 [0.0021], P < .001). The link was more pronounced in participants under 65 and those who were underweight (Pinteraction < .01). Per standard deviation increment of UPF intake was linked to 10.5% and 2.7% higher risks of incident hip fractures (HR, 95% CI: 1.105, 1.029-1.186; P < .01) and all fractures (HR, 95% CI: 1.027, 1.000-1.055; P < .05), respectively. Our results suggest that higher UPF intake is associated with lower BMD and increased risk of fractures captured in hospital inpatient records, highlighting the need for dietary interventions to protect bone health.
The Niagara Escarpment in Hamilton, Ontario, presents significant geohazards, such as block failure, threatening human safety and infrastructure. Despite thorough documentation of the stratigraphy exposed along the escarpment, there remains a lack of quantitative assessment of the rock mass characteristics. This study addresses this gap and offers practical approaches to documenting rock mass characteristics by investigating rock strength properties. The Schmidt hammer (SH), a non-destructive tool widely used in geotechnical and geomorphological research, was used to compare the strength values of rock units exposed along the Niagara Escarpment in Hamilton. Systematic field investigations across selected sites used scanline surveys to measure weathering, fracture continuity, groundwater presence and SH values. The SH rebound values were qualitatively compared with those reported in previous literature and align with lithological expectations. Findings indicate that SH values are significantly influenced by both geographic location and geological formation, with a significant interaction effect. Comparative analysis of rock units in the Ancaster Member of the Goat Island Formation, the Gasport Formation and the Irondequoit Formation showed significant differences (p < 0.005) in rock hardness, with mean SH values of 32.8, 42.2 and 49.1, respectively. These findings demonstrate the necessity of integrating stratigraphic and site-specific geological data into hazard mitigation strategies, as rock hardness influences the stability of the escarpment face. The data reported here demonstrate rock strength variation along the Niagara Escarpment and contribute to the modelling and prediction of geohazards, thereby enhancing geohazard management strategies in similar regions.
Antiseizure medications (ASMs) have endocrine related side effects. Long term use of ASMs may result in menstrual irregularities, sexual dysfunction, anovulatory cycles, polycystic ovaries, and reduced fertility. Some ASMs also interfere with glucose and bone metabolism, as well as normal thyroid function. Other ASMs may result in syndrome of inappropriate ADH secretion (SIADH) and hyponatremia. Epilepsy patients treated with ASMs are at risk for bone loss and fractures. This chapter explores the endocrine and hormonal effects of antiseizure medications.
Premodern medicine used a variety of mineral substances for therapeutic purposes. The present article deals with pitch-asphalt, and, in particular, a precious kind of it called mūmiyāʾ originating in Persia. It was first described in detail in the Arabic pharmacological tradition, and its fame spread throughout the medieval Mediterranean, including Byzantium. By editing and examining for the first time a previously unexplored medieval Greek text on mūmiyāʾ, this study offers new insights into the medicinal uses of this substance. It also significantly increases our understanding of the intense cross-cultural transfer of medical knowledge from the Islamicate world to Byzantium by showing that this was not merely based on the translation of a few Arabic medical works into Greek, but was a multifaceted phenomenon involving a complex nexus of sources that require further investigation.
The concept of superposed fracture networks consisting of different generations, and often types, of fractures that have developed sequentially is discussed. Superposed networks can consist of different types of extension or shear fractures, and each fracture may abut, cross or follow (reactivate) earlier fractures. An example of a superposed fracture network in Liassic limestones in Somerset, UK, is presented, which comprises two sets of veins and a later joint network. The veins develop as damage zones around faults, with veins of the later set crossing or trailing along the earlier set. The later joints either cross-cut the earlier veins or reactivate them, the latter being common for the thicker (more than about 5 mm) veins. The veins and joint networks have markedly different geometries and topologies. The veins are spatially clustered and are typically dominated by I-nodes, while the joints are more evenly distributed and tend to be dominated by Y-nodes. The combined network of veins and joints at Lilstock is dominated by X-nodes because so many joints cross-cut the earlier veins. Understanding the development of superposed fracture networks leads to better understanding of the kinematic, mechanical, tectonic and fluid flow history of rocks.
Orogenic forelands host interactions between deformation and static or migrating fluids. Given their accessibility and dimensions, these areas are not only historic landmarks for structural geology, but they are also areas of prime interest for georesource exploration and geological storage, and loci of potential geohazards. Geochemical techniques applied on cements filling tectonic structures and associated trapped fluids can constrain the temperature, pressure, origin and pathways of fluids during deformation and allow the characterization of the past fluid system. In this review focused on calcite cements, we first present and critically discuss the most used geochemical techniques to appraise specific parameters of the fluid system. Second, we summarize the outcomes of selected case studies where the past fluid system was reconstructed with consideration of tectonics, either at the scale of the individual fold/thrust or at the scale of the fold-and-thrust belt. At first order, the past fluid system evolves in a similar way with respect to the considered stage of deformation, being rather closed to external fluids when deformation is bounded to mesoscale structure development, and opening to vertical flow when thrust and folds develop. In a more detailed view, it seems that the past fluid system evolves and distributes under the influence of the structural style, of the geometry of the major faults and of the lithology of the sedimentary succession. Through this review, we illustrate the concept of geochemistry-assisted structural geology through case studies where the geochemistry of calcite veins constrained subsurface geometries and structural developments in orogenic forelands.
Stoats (Mustela erminea) are active hunters and, therefore, one might predict that any broken bones or other injuries impeding active movement would incur a serious risk of starvation. Dead stoats (n = 560) were collected from trappers operating predator control lines in three conservation areas of New Zealand from 1972-1978. Femurs were cleaned and examined for healed injuries and deformities. Five femurs from four stoats (one with both femurs injured) showed traumatic distortions following healing of complete breaks incurred during life. A further case recorded during post-eradication monitoring in 2010 on Rangitoto, an offshore island, is added. These data provide evidence that wild stoats have a remarkable capacity to tolerate catastrophic femur fractures. They can survive long enough, despite the implied limitation to their energetic hunting style, to permit full healing even though the result is a gross distortion of the femoral shaft.
The Niagara Escarpment is a fractured Palaeozoic sedimentary cuesta, subject to year-round weathering in a temperate climate. We examined the temperature of the rock surface and fractures at three in situ sites with varying aspect and lithology, as well as the surface and interior of three control blocks maintained in outdoor conditions between December 2020 and March 2021. The objectives were to examine the interplay between freeze–thaw and thermal weathering in the winter months and to identify potential factors influencing these processes. Both diurnal-scale and prolonged freeze–thaw cycles differing in spatial and temporal extent were identified, coincident with periods of high moisture. We frequently observed rapid temperature changes (>1 °C min−1) at sites with strong insolation, which implies that the temperature regime is suitable for thermal shock and fatigue to occur. Site-specific factors, such as the aspect of the escarpment face and lithology, impact the mechanism and extent of weathering. Southeast-facing sites with high insolation are dominated by diurnal-scale freeze–thaw; west- and east-facing sites with lower insolation experience a more prominent prolonged freeze–thaw cycle. Across all sites there is a gradient between surface and fracture temperature that follows diurnal trends in air temperature and insolation. Variability in the surface-fracture gradient may enhance weathering processes by shifting the orientation and magnitude of stress, and by changing the spatial distribution of freezing and thawing. Our research indicates that site-specific factors and pre-existing fractures moderate the influence of air temperature and insolation on thermal gradients, and ultimately the weathering regime.
The Niagara Escarpment is a geological feature located in southern Ontario, Canada, and the northeastern United States, comprising highly fractured sandstone, shale and carbonates deposited during the Ordovician and Silurian periods. Differential erosion of the strata has generated a steep cliff face which bisects the city of Hamilton, Ontario. Geological fractures are widespread in the escarpment and result in the formation of unstable blocks of rock subject to erosion through rockfall. This presents structural stability issues of concern due to the proximity of the escarpment to urban infrastructure. We quantify and analyse fracture networks in the escarpment using a combined field- and numerical-modelling-based approach. The location, orientation and aperture of fractures were documented from local outcrops using scanline and area survey methods. Clusters of poles describing the orientation of geological discontinuities were identified in spherical projections, defining three sets: (1) a sub-vertical stratabound set striking N–S, (2) a sub-vertical stratabound set striking E–W, and (3) a set parallel to horizontal sedimentary bedding planes which we infer controlled sub-vertical fracture geometry. Discrete fracture network modelling of fracture sets highlights their high degree of connectivity, and contribution to local geohazards, and quantifies their role in controlling fluid flow through escarpment strata, which is dependent on fracture aperture. Additionally, bedding planes have the potential to act as free surfaces, facilitating stress conditions in which approximately cuboid blocks are produced, and increasing the risk of rockfalls. We conclude that fractures present a first-order control on the fluid-flow properties and stability of the Niagara Escarpment.
Understanding the distribution and geometry of faults and fractures is critical for predicting both subsurface permeability architecture and the integrity of geological fluid barriers, particularly in rocks with low primary porosity and permeability. While fracture patterns in relatively competent, weathering-resistant (therefore often well-exposed) rocks are generally well studied in outcrop, the role of mechanically weak layers in defining fracture patterns is frequently overlooked or under-represented. Here we show that rock composition, specifically clay and silicate minerals versus carbonate content, exerts a strong control on fault and fracture propagation and bed-containment within a mechanically layered, Cretaceous carbonate sequence at Canyon Lake Gorge, Texas. We find that relatively incompetent, clay-rich layers limit fault and fracture propagation, and cause bed-containment of fractures in more competent beds. In our results, no clear relationships exist between mechanical layer thickness and fracture abundance. These results are important for understanding the relative importance of composition versus bed thickness on fracture abundance in the subsurface, and for predicting fracture-controlled fluid flow pathways, seals and fracture connectivity across beds with variable compositions, thicknesses and competences.
Bedding-perpendicular joints striking parallel (longitudinal) and perpendicular (transverse) to both the axis of the hosting anticline and the trend of the foredeep-belt system are widely recognized in fold-and-thrust belts. Their occurrence has been commonly attributed to folding-related processes, such as syn-folding outer-arc extension, although they can also be consistent with a pre-folding foredeep-related fracturing stage. Here we report the pre-folding fracture pattern affecting the Pietrasecca Anticline, in the central Apennines (Italy), resolved by a detailed field structural analysis. Field observations, scan-lines and interpretation of virtual outcrops were used to study the intensity, distribution and the orientations of fracture pattern along the anticline. The fracture pattern of the Pietrasecca Anticline consists of longitudinal and transverse joints, oriented approximately perpendicular to bedding, and of a pre-folding longitudinal pressure-solution cleavage set, which is oblique to bedding regardless of the bedding dip. Cross-cutting relationships show that joints predated the development of the pressure-solution cleavage. Furthermore, joint intensity does not relate to the structural position along the anticline. Taken together, these observations suggest that jointing occurred in a foredeep environment before the Pietrasecca Anticline growth. Our work further demonstrates that joints striking parallel and orthogonal to the main fold axis do not necessarily represent syn-folding deformation structures.
The upr module in the MATLAB Reservoir Simulation Toolbox (MRST) can construct unstructured Voronoi grids that conform to polygonal boundaries and geometric constraints in arbitrarydimensions prescribed inside the reservoir volume. The resulting volumetric tessellations are usually realized as locally orthogonal, perpendicular bisector (PEBI) grids, in which cell faces can be aligned to accurately preserve objects of codimension one (curves in 2D and surfaces in 3D) and/or cell centroids can be set to follow curves in 2D or 3D. This enables you to accurately model faults, let grid cells follow horizontal and multilateral well paths, or create lower-dimensional or volumetric representations of fracture networks. The module offers methods for improving grid quality, like configurable policies for treating intersecting geometric object and handling conflicts among constraints, methods for locating and removing conflicting generating points, as well as force-based and energy-minimization approaches for optimizing the grid cells. You can use \mcode{upr} to create a consistent hierarchy of grids that represent the reservoir volume, the constraining geometric objects (surfaces and curves), as well as their intersections. The hierarchy is built such that the cell faces of a given (sub)grid conform to the cells of all bounding subgrids of one dimension lower.
Fractures are often implicitly represented in models used to simulate flow in fractured porous media. This simplification results in smaller models that are computationally tractable. As computational power continues to increase, there has been growing interest in simulation methods that explicitly represent fractures. The embedded discrete fracture model (EDFM) is one such method. In EDFM, fracture and matrix grids are constructed independently. The grids are then coupled to each other via source/sink relations. This modeling approach makes EDFM versatile and easy to use. EDFM has been shown to be able to handle complex fracture networks. The grid construction process is also straightforward and requires minimal fine-tuning. Within academia and industry, EDFM has been used to study geothermal energy production, unconventional gas production, multiphase flow in fractured reservoirs, and enhanced oil recovery processes. In this chapter, the mathematical formulation of EDFM is introduced. We then demonstrate the usage of EDFM via three examples. The first example involves a simple fracture network containing only three fractures. The second involves upscaling a stochastically generated fracture network. Finally, a well test will be simulated in a publicly available data set sourced from the Jandaira carbonate formation in Brazil.
The metavolcanics of Chitradurga region host numerous shallow crustal veins and fractures and faults of multiple orientations. Several high and low Pf cycles have been recorded in the region, leading to the reactivation of most of the pre-existing fractures for high Pf and selective reactivation of some well-oriented fractures under low Pf conditions. The pre-existing anisotropy (magnetic fabric) in the metavolcanics acted as the most prominent planar fabric for fracture propagation and vein emplacement under both conditions, thereby attaining maximum vein thickness. In this study, we emphasize the reactivation propensity of these pre-existing fracture planes under conditions of fluid pressure variation, related to the high and low Pf cycles. Multiple cycles of fluid-induced fracture reactivation make it difficult to quantify the maximum/minimum fluid pressure magnitudes. However, in this study we use the most appropriate fluid pressure magnitudes mathematically feasible for a shallow crustal depth of ∼2.4 km. We determine the changes in the reactivation potential with states of stress for the respective fracture orientations under both high and low Pf conditions. Dependence of fluid pressure variation on the opening angle of the fractures is also monitored. Finally, we comment on the failure mode and deformation behaviour of the fractures within the prevailing stress field inducing volumetric changes at the time of deformation. We find that deformation behaviour is directly related to the dip of the fracture planes.
Electroconvulsive therapy (ECT) remains a valuable treatment for major depression with psychotic symptoms. However, it is necessary to pay special attention when there is a history of fractures.
Objectives
Through the description of the following clinical case, we will emphasize the importance of screening for vertebral fractures within ECT and the different procedures that must be taken if that occurs.
Methods
We undertook a narrative literature review by performing a search on PubMed for English-written articles. The query used was “Electroconvulsive Therapy” AND “Vertebral Fractures”.
Results
A 71-year-old woman was admitted with an episode of psychotic depression. Basic tests were performed and were all normal. After not responding to pharmacologic treatment, she was referred for ECT. The patient had a full recovery after 4 weeks of biweekly sessions. She was discharged and proposed for maintenance ECT. However, she started complaining of back pain after falling and did an X-ray and CT scan which revealed fractured L1 and L2. It was suggested conservative treatment with a Jewett orthosis. Within this period, the ECT was suspended and after a 4-week treatment, the fracture was consolidated. As there was no risk of neurological compression, the treatment was restarted with the same dosage of succinylcholine, and it was achieved complete muscular relaxation. The patient fully recovered without any orthopedic sequel.
Conclusions
Electroconvulsive therapy can be safely performed after conservative treatment of vertebral fractures, if special attention is provided to complete muscular relaxation. For this effect, the dosage of succinylcholine can be adjusted.
Introduction: Fractures are a common childhood presentation to the emergency department (ED). While ED providers are aware of treating pain, we are less aware of the functional impact of these fractures. Eighty percent of children with a fracture experience compromise in their daily function. Understanding the functional outcomes of fractures will help optimize discharge instructions for at-home care. The primary objective of our study was to describe caregivers' perspectives on the impact of their child's fracture on: (1) child functioning, (2) caregiver functioning and (3) family life. Methods: We performed a qualitative study interviewing caregivers of children (5 to 11 years) who received care for acute (< 24 hours old), non-operative long bone fractures at a Canadian tertiary care pediatric ED. Audio-recorded, semi-structured telephone interviews were completed 1-2 weeks post-ED visit, until thematic saturation was achieved. Transcripts were read and coded by two researchers concurrent with data collection. We applied content analysis to the interview material, explicating themes to summarize the data utilizing NVivo software. Results: Twenty-five interviews were completed. Most children (23/25) suffered upper extremity fractures and most participants were mothers (21/25). All caregivers reported a change in their child's function. The most commonly affected areas included: sleep, play and activities of daily living (ADL's; ie. dressing, bathing, eating). Children were impacted by pain and related negative emotional responses. All children required additional help from their caregivers to carry out ADL's. Strategies included changing household routines and missing work. Importantly, caregivers described a disrupted family dynamic. Adapting to their injured child's functional deficits and caring for pain and distress took time and attention away from the household's previously well-functioning routine. This burden was felt by all family members. Key concerns from caregivers included pain management, fracture healing/complications, and regression of their child's independence. Conclusion: Function is universally impaired in younger children with fractures. We suggest 5 main points to include in discharge instructions: (1) monitoring pain and providing analgesia, (2) helping children with ADL's, even if previously independent, (3) allotting extra time for morning and bedtime routines, (4) offering safe choices for play and (5) coaching children in positive thinking and problem-solving.