Absence Of Fracture Research Articles

Numerical simulation of wormhole propagation in fractured carbonate rocks during acidizing using a simplified Stokes–Brinkman model

Most numerical simulations for modeling acid reactive fluid transport and wormhole propagation during matrix acidizing, waterflooding, and CO2 sequestration in carbonate formations are computationally expensive, limiting real-time reservoir management and deep learning training datasets generation for inverse modeling research. Therefore, there is a need for less computationally expensive acid-reactive fluid flow models with adequate accuracy. This study developed and validated a simplified acid reactive-transport model by integrating a simplified Stokes–Brinkman model (as opposed to Darcy’s law), an averaged continuum model, and a pseudo-fracture model. Using FEniCS, the model effectively simulates acid-reactive fluid transport and wormhole propagation in carbonate rocks, achieving a high R-square value of about 0.97 based on a quantitative comparison of the breakthrough volume with other models. The simplified model can also simulate wormhole propagation for the reciprocal of the Damköhler number (1/Da) ranging from 0.001 to 1 with adequate accuracy. Sensitivity studies on the natural fracture parameters such as orientation, length, width, and density showed that higher fracture density, wider fracture aperture, longer fracture length, and orientation aligned with the direction of acid injection contribute to lower pore volume to breakthrough ratio but may not increase long-term acid stimulation efficiency. Also, the presence or absence of fractures in the matrix does not alter the dissolving patterns and optimum injection rate. This simple acid reactive-transport model can generate large training datasets for developing surrogate models in deep learning research. Finally, the FEniCS code in this paper is shared so future researchers can reproduce the results or extend the research work.

Mechanical consequences to the annulus fibrosus following rapid internal pressurization and endplate fracture under restrained-expansion conditions

Intervertebral disc herniation is not a common injury in the adolescent population, but the correlation between trauma and herniation warrants concern. Previous research demonstrated the capacity for rapid internal pressurization to reduce the mechanical integrity of the intervertebral disc's annulus fibrosus, even in the absence of fracture. The purpose of this study was to modify previous internal pressurization procedures towards a more transferable injury model, then investigate the capacity for these procedures to damage the mechanical integrity of the annulus fibrosus. Porcine cervical motion segments with intact facet joints were confined between a vice and force plate under 300 N of static compression, then a single, manual, rapid internal pressurization was delivered. Posterolateral annulus samples were extracted and situated in a 180° peel test configuration, exposing the interlamellar matrix of samples to separations of 0.5 mm/s, until complete separation of the sample occurred. Multilayer tensile testing was performed on superficial and mid-span samples of annulus by applying uniaxial tension of 1 %/s to 50 % strain. Compared to unpressurized controls, rapid pressurization causing fracture resulted in reduced lamellar adhesion and increased toe-region stress and strain properties in the annulus. Morphological assessment reported similar fracture patterns between endplate fractures achieved in the present experiment and endplate fractures documented in human patients. Mechanical plus morphological results suggest that rapid internal pressurization resulting in endplate fracture may represent a potent mechanism for subsequent damage to the intervertebral disc.

An overview of the performance of AI in fracture detection in lumbar and thoracic spine radiographs on a per vertebra basis

PurposeSubtle spinal compression fractures can easily be missed. AI may help in interpreting these images. We propose to test the performance of an FDA-approved algorithm for fracture detection in radiographs on a per vertebra basis, assessing performance based on grade of compression, presence of foreign material, severity of degenerative changes, and acuity of the fracture.MethodsThoracic and lumbar spine radiographs with inquiries for fracture were retrospectively collected and analyzed by the AI. The presence or absence of fracture was defined by the written report or cross-sectional imaging where available. Fractures were classified semi-quantitatively by the Genant classification, by acuity, by the presence of foreign material, and overall degree of degenerative change of the spine. The results of the AI were compared to the gold standard.ResultsA total of 512 exams were included, depicting 4114 vertebra with 495 fractures. Overall sensitivity was 63.2% for the lumbar spine, significantly higher than the thoracic spine with 50.6%. Specificity was 96.7 and 98.3% respectively. Sensitivity increased with fracture grade, without a significant difference between grade 2 and 3 compression fractures (lumbar spine: grade 1, 52.5%; grade 2, 72.3%; grade 3, 75.8%; thoracic spine: grade 1, 42.4%; grade 2, 60.0%; grade 3, 60.0%). The presence of foreign material and a high degree of degenerative changes reduced sensitivity.ConclusionOverall performance of the AI on a per vertebra basis was degraded in clinically relevant scenarios such as for low-grade compression fractures.

Study on Flow Line Characteristics and Well Test Interpretation Methods of Multi Branch Fractured Wells in Dual Porous Media

Fractured reservoirs have developed fractures, strong heterogeneity, and complex seepage patterns. The analysis of core and imaging logging data in Bohai BZ Oilfield shows that there are a large number of fractures developed in the formation, with some wells having up to 6-8 fractures per meter. To study the impact of fractures on seepage, a multi fracture system seepage field simulation method was established, and the characteristic curves of flow lines under different fracture shapes were drawn. The fracture flow line morphology shows that there is a significant difference in the distribution of flow lines between the presence and absence of fractures, and the location of the fractures The size and shape of the reservoir have varying degrees of influence on the distribution of the streamline. The streamline around the well is distributed radially around it. When the fluid encounters an area with developed fractures, it first flows into the fractures and then flows from the fractures towards the wellbore. At the same time, based on the characteristics of fracture development in BZ oilfield and the theory of vertical fracture well testing, a dual medium multi fracture system oil well testing model was established. The model was numerically solved using Laplace transform, and a dual logarithmic curve chart for dual pore medium multi branch fracture well testing was obtained. The effects of fracture branching number, fracture length, conductivity coefficient ratio, and fracture conductivity on the shape of the testing curve were analyzed. The established well testing interpretation model can analyze oilfield stratigraphic information, reservoir fracture development, and boundary conditions. The research results have important guiding significance for evaluating the dynamic performance of oil wells in a dual pore medium multi fracture system and designing oilfield development plans.

Treatment of Acute Traumatic Central Cord Syndrome: A Study of North American Trauma Centers.

Central cord syndrome (CCS) is expected to become the most common traumatic spinal cord injury, yet its optimal management remains unclear. This study aimed to evaluate variability in nonoperative vs operative treatment for CCS between trauma centers in the American College of Surgeons Trauma Quality Improvement Program, identify patient- and hospital-level factors associated with treatment, and determine the association of treatment with outcomes. Adults with CCS were identified from the Trauma Quality Improvement Program database (2014-2016). Mixed-effects modeling with a random intercept for trauma centers was used to examine the adjusted association of patient- and hospital-level variables with nonoperative treatment. The random-effects output of the model assessed the risk-adjusted variability in nonoperative treatment across centers. Outlier hospitals were identified, and the median odds ratio was calculated. The adjusted effect of nonoperative treatment on mortality, morbidity, and hospital length of stay (LOS) was examined at the patient and hospital level by mixed-effects regression. Three thousand, nine hundred twenty-eight patients across 255 centers were eligible; of these, 1523 (38.8%) were treated nonoperatively. Older age, noncommercial insurance (odds ratio [OR] 1.26, 95% CI 1.08-1.48, P = .004), absence of fracture (OR 0.58, 95% CI 0.49-0.68, P < .001), severe head injury (OR 1.41, 95% CI 1.09-1.82, P = .008), and comatose presentation (1.82, 95% CI 1.15-2.89, P = .011) were associated with nonoperative treatment. Twenty-eight hospitals were outliers, and the median odds ratio was 2.02. Patients receiving nonoperative treatment had shorter LOS (mean difference -4.65 days). Nonoperative treatment was associated with lesser in-hospital morbidity (OR 0.49, 95% CI 0.37-0.63, P < .001) at the patient level. There was no difference in mortality. Operative decision-making for CCS is influenced by patient factors. There remains substantial variability between trauma centers not explained by case-mix differences. Nonoperative treatment was associated with shorter hospital LOS and lesser inpatient morbidity.

Bone bruise vs. non-displaced fracture on MRI: a novel grading system for predicting return-to-play.

To devise an MRI grading scheme for osseous contusion patterns in elite hockey players for predicting return-to-play (RTP). A retrospective review was performed to identify traumatic lower extremity osseous injuries in professional hockey players. A total of 28 injuries (17 players) were identified over a 10-year period. All had MRIs acquired at ≥ 1.5T within a mean interval of 2days from initial injury. MRIs were retrospectively reviewed by 3 musculoskeletal radiologists for osseous contusion pattern, classified as grade 1 (mild), 2 (moderate), or 3 (severe). Grade 3 contusions were further subdivided by the presence or absence of fracture, defined as discrete cortical disruption on MRI or follow-up CT. RTP was calculated from date of injury to next game played based on game log data. Statistical analysis was performed using ANOVA and post hoc unpaired t test. Mean RTP for grade 1, 2, and 3 injuries was 2.8, 4.5, and 20.3days, respectively. Grade 3 injuries without and with cortical fractures had mean RTP of 18.3 and 21.4days, respectively. ANOVA analysis between groups achieved statistical significance (p < 0.001). Post hoc t test demonstrated statistically significant differences between grade 3 and grades 1 (p < 0.001) and 2 (p < 0.001) injuries. There was no statistical difference in RTP between grade 3 subgroups without and with fracture (p = 0.327). We propose a novel MRI grading system for assessing severity of osseous contusions and predicting RTP. Clinically, there was no statistically significant difference in RTP between severe osseous contusions and nondisplaced fractures in elite hockey players.

A Simulation Model for the Handheld Ultrasound Diagnosis of Pediatric Forearm Fractures.

Handheld ultrasound (HHU) devices have gained prominence in emergency care settings and post-graduate training, but their application in the diagnosis of pediatric fractures remains under-explored. The aim of this study is to evaluate the effectiveness and accuracy of an HHU device for diagnosing pediatric forearm fractures using a simulation model. The materials for the basic pediatric fracture model include turkey bones soaked in white vinegar to make them pliable, food-grade gelatine, and plastic containers. Ultrasound analysis of the models was done with an HHU device, Sonosite İViz US (FUJIFILM Sonosite, Inc.; Bothell, Washington USA). Four different fracture patterns (transverse fracture, oblique fracture, greenstick fracture, and a torus fracture) and one model without fracture were used in this study. Twenty-six Emergency Medicine residents sonographically evaluated different bone models in order to define the presence and absence of fracture and the fracture subtype. The participants' ability to obtain adequate images and the time taken to create and recognize the images were evaluated and recorded. After the sonographic examination, the residents were also asked for their opinion on the model as a teaching tool. All participants (100%) recognized the normal bone model and the fracture, regardless of the fracture type. The consistency analysis between the practitioners indicated a substantial agreement (weighted kappa value of 0.707). The duration to identify the target pathology in fracture models was significantly longer for the greenstick fracture (78.57 [SD = 30.45] seconds) model compared to other models. The majority of participants (92.3%) agreed that the model used would be a useful teaching tool for learning ultrasound diagnosis of pediatric forearm fractures. All participants successfully identified both the normal bone model and the presence of fractures, irrespective of the fracture type. Significantly, the identification of the greenstick fracture took longer compared to other fracture types. Moreover, the majority of participants acknowledged the model's utility as a teaching tool for learning ultrasound diagnosis of pediatric forearm fractures.

Radiologic blind spots in hip and pelvic radiographs.

The purpose of our study was to identify the locations at which hip and pelvic fractures are commonly missed on radiographs. A retrospective study was performed at four non-Level 1 trauma center emergency departments. IRB approval was obtained. All emergency department hip or pelvic radiographs with subsequent CT performed within 48h were identified from 2017 to 2022. Reports for each radiograph and CT were scored for the presence or the absence of fracture in the following locations: ilium, sacrum, superior pubic ramus, inferior pubic ramus, pubis, acetabulum, subcapital femoral, femoral neck, greater trochanter, lesser trochanter, intertrochanteric, and subtrochanteric. The CT report was used as the gold standard. The false-negative radiography cases were reviewed on a PACS workstation to determine whether the case had an "unexpected miss" of a fracture, a subtle fracture, radiographically occult fracture, or exam was limited by artifact. The percentage of missed fractures at each location was calculated. Nine hundred seventy-five radiography cases with subsequent CT were identified. One hundred forty-six cases did not meet entry criteria; therefore, 829 cases were analyzed further. Seventy-four percent of patients were female with age of 74 ± 16 (mean ± standard deviation) years (range 1-103). Three hundred fifty-two cases had at least one fracture, and many cases had multiple fractures. There were 68 false-negative cases. The most commonly missed fractures by percentage were pubis, ilium, and greater trochanter. The most common unexpectedly missed fractures were greater trochanter and femoral subcapital. A careful systematic evaluation of hip and pelvic radiographs, with particular attention to the pubis, ilium, greater trochanter, and subcapital region, may improve radiographic fracture detection and decrease delays in diagnosis.

Analogy test rig for the generation of tooth flank fractures at large gears (WZL-double pulsator)—commissioning and first test results

As a result of the enhanced of load-carrying capacity with regard to pitting and tooth root breakage, generation of tooth flank fractures became more frequent. This type of damage differs from existing fatigue damages on the tooth flank in that crack initiation takes place below the case hardened surface layer and the tooth breaks in the area of the active tooth flank. An isolated investigation of tooth flank fractures is currently not possible because there is no analogy test rig available that can reproduce both, the compressive stress due to Hertzian contact flattening as well as the tensile stress due to tooth bending. For this reason, a test rig concept is being developed, manufactured and put into operation in the DFG research project “Analogy test rig for tooth flank fractures”, which allows the generation of tooth flank fractures in absence of other damage types. This report deals with the commissioning of the WZL-Double Pulsator as well as first test results. The FE model of the analogy test rig is validated by measuring tooth root strains with strain gauges and comparing them with the calculated strains. Finally, the commissioning is carried out and first tests are performed.

Lumbar osteoporotic fractures develop in segments with less degenerated discs which then become more degenerated.

Our aim was to study the influence of segmental variations in intervertebral disc degeneration on the location of acute osteoporotic compression fractures and to investigate chronic effect of such fractures on adjacent discs. This retrospective study included 83 patients (69 females; mean ± SD age: 72.3 ± 14.0years) with osteoporotic vertebral fractures. Using lumbar MRI, two neuroradiologists evaluated 498 lumbar vertebral segments for the presence and acuity of fractures and graded adjacent intervertebral disc degeneration on Pfirrmann's scale. Absolute and relative (to average patient-specific degeneration grade) segmental degeneration grades were compared against the presence and chronicity of vertebral fractures for all segments and for upper (T12-L2) and lower (L3-L5) subgroups. Intergroup analysis was conducted using Mann-Whitney U tests, withpvalue of < .05 considered significant. Fractures involved 149/498 (29.9%; 15.1% acute) vertebral segments, majority (61.1%) involving T12-L2 segments. Segments with acute fractures had significantly lower degeneration grades (mean ± SD: absolute: 2.72 ± 0.62; relative: 0.91 ± 0.17) than those with no (absolute: 3.03 ± 0.79, p = 0.003; relative: 0.99 ± 0.16, p < 0.001) or chronic fractures (absolute: 3.03 ± 0.62, p = 0.003; relative: 1.02 ± 0.16, p < 0.001). Degeneration grades were higher in the lower lumbar spine (p < 0.001) in the absence of fractures, but comparable to upper spine for segments with acute or chronic fractures (p = 0.28 and 0.56, respectively). Osteoporotic vertebral fractures favour segments with lower burden of disc degeneration, but likely contribute to subsequent worsening of adjacent disc degeneration.

Serum bone remodeling parameters and transcriptome profiling reveal abnormal bone metabolism associated with keel bone fractures in laying hens

Keel bone fractures affect welfare, health, and production performance in laying hens. A total of one hundred and twenty 35-wk-old Hy-line Brown laying hens with normal keel (NK) bone were housed in furnished cages and studied for ten weeks to investigate the underlying mechanism of keel bone fractures. At 45 wk of age, the keel bone state of birds was assessed by palpation and X-ray, and laying hens were recognized as NK and fractured keel (FK) birds according to the presence or absence of fractures in keel bone. The serum samples of 10 NK and 10 FK birds were collected to determine bone metabolism-related indexes and slaughtered to collect keel bones for RNA-sequencing (RNA-seq), Micro-CT, and histopathological staining analyses. The results showed that the concentrations of Ca, phosphorus, calcitonin, 25-hydroxyvitamin D3, and osteocalcin and activities of alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP) in serum samples of FK birds were lower than those of NK birds (P < 0.05), but the concentrations of parathyroid hormone, osteoprotegerin, and corticosterone in serum samples of FK birds were higher than those of NK birds (P < 0.05). TRAP staining displayed that FK bone increased the number of osteoclasts (P < 0.05). Micro-CT analysis indicated that FK bone decreased bone mineral density (P < 0.05). Transcriptome sequencing analysis of NK and FK bones identified 214 differentially expressed genes (DEGs) (|log2FoldChange| > 1, P < 0.05), among which 88 were upregulated and 126 downregulated. Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analysis indicated that 14 DEGs related to skeletal muscle movement and bone Ca transport (COL6A1, COL6A2, COL6A3, PDGFA, MYLK2, EGF, CAV3, ADRA1D, BDKRB1, CACNA1S, TNN, TNNC1, TNNC2, and RYR3) were enriched in focal adhesion and Ca signaling pathway, regulating bone quality. This study suggests that abnormal bone metabolism related to keel bone fractures is possibly responded to fracture healing in laying hens.

Tumor-induced osteomalacia treated with T12 tumor resection

Tumor-induced osteomalacia (TIO) is a rare form of osteomalacia caused by fibroblast growth factor-23 (FGF23)-secreting tumors. Most of these tumors are phosphaturic mesenchymal tumors (PMTs) typically involving soft tissue in the extremities and bone of the appendicular skeleton and cranium. We report the case of a 60-year-old woman with about 3 years of persistent bone pain and multiple fractures, initially diagnosed as osteoporosis, who was found to have hypophosphatemia with low 1,25-dihydroxyvitamin D and elevated alkaline phosphatase and inappropriately normal FGF23 consistent with TIO. Her symptoms improved with phosphate supplementation, vitamin D and calcitriol. 68Ga-DOTATATE imaging revealed a T12 vertebral body lesion confirmed on biopsy to be a PMT. She underwent resection of the PMT with resolution of TIO and increased bone density. This rare case of TIO secondary to a PMT of the thoracic spine highlights some of the common features of PMT-associated TIO and draws attention to PMT-associated TIO as a possible cause of unexplained persistent bone pain, a disease entity that often goes undiagnosed and untreated for years. Tumor-induced osteomalacia (TIO) is typically caused by phosphaturic mesenchymal tumors (PMTs) that are usually found in the soft tissue of the extremities and bone of the appendicular skeleton/cranium and rarely in the spine. TIO may be misdiagnosed as osteoporosis or spondyloarthritis, and the correct diagnosis is often delayed for years. However, osteoporosis, in the absence of fracture, is not associated with bone pain. The hallmark of TIO is hypophosphatemia with inappropriately normal or low 1,25-dihydroxyvitamin D and elevated or inappropriately normal fibroblast growth factor-23 (FGF23) levels. In patients with unexplained persistent bone pain, a serum phosphate should be measured. Consider PMT-associated TIO as a potential cause of unexplained persistent bone pain and hypophosphatemia. PMTs express somatostatin receptors and may be identified with 68Ga-DOTATATE imaging. Complete surgical resection is the preferred treatment for spinal PMTs associated with TIO.

M2ABQ-a proposed refinement of the modified algorithm-based qualitative classification of osteoporotic vertebral fractures.

The current methods to classify osteoporotic vertebral body fractures are considered ambiguous; there is no reproducible, accepted gold standard. The purpose of this study is to refine classification methodology by introducing clear, unambiguous rules and a refined flowchart to allow consistent classification of osteoporotic vertebral body fractures. We developed a set of rules and refinements that we called m2ABQ to classify vertebrae into five categories. A fracture-enriched database of thoracic and lumbar spine radiographs of patients 65years of age and older was retrospectively obtained from clinical institutional radiology records using natural language processing. Five raters independently classified each vertebral body using the m2ABQ system. After each annotation round, consensus sessions that included all raters were held to discuss and finalize a consensus annotation for each vertebral body where individual raters' evaluations differed. This process led to further refinement and development of the rules. Each annotation round showed increase in Fleiss kappa both for presence vs absence of fracture 0.62 (0.56-0.68) to 0.70 (0.65-0.75), as well as for the whole m2ABQ scale 0.29 (0.25-0.33) to 0.54 (0.51-0.58). The m2ABQ system demonstrates moderate interobserver agreement and practical feasibility for classifying osteoporotic vertebral body fractures. Future studies to compare the method to existing studies are warranted, as well as further development of its use in machine learning purposes.

Divergent mechanical properties of older human male femora reveal unique combinations of morphological and compositional traits contributing to low strength.

Bone strength is generally thought to decline with aging and prior work has compared traits between younger and older cohorts to identify the structural and compositional changes that contribute to fracture risk with age. However, for men, the majority of individuals do not fracture a bone in their lifetime. While fracture occurrence is multifactorial, the absence of fracture in the majority of males suggests that some individuals maintain bone strength or do not lose enough strength to fracture, whereas others do lose strength with aging. Consequently, not all structural and material changes observed with age may lead to strength-decline. We propose that consideration of different subgroups of older individuals will provide a more precise understanding of which structural and material changes directly contribute to strength-decline. We identified subgroups using latent profile analysis (LPA), which is a clustering-based algorithm that takes multiple continuous variables into account. Human cadaveric male femoral diaphyses (n=33, 26-89years) were subjected to whole bone and tissue-level mechanical tests. Morphological traits, porosity, and cortical tissue mineral density (Ct.TMD) were obtained, as were measures of enzymatic cross-links and the advanced glycation end product, pentosidine (PEN). A univariate analysis first identified a younger cohort (YNG, n=11) and older cohort (n=22). LPA was then conducted using three mechanical traits (whole bone strength, tissue-level strength, and tissue-level post-yield strain), resulting in a further stratification of the older group into two similarly aged groups (p=0.558), but one with higher (OHM, n=16) and another with lower mechanical properties (OLM, n=6). The OLM group exhibited lower whole bone strength (p=0.016), tissue-level strength (p<0.001), and tissue-level post-yield strain (p<0.001) compared to the YNG group. Meanwhile, the OHM only exhibited significantly lower tissue-level post-yield strain (p<0.001), compared to the YNG group. Between the two older groups, the OHM group exhibited higher whole bone strength (p=0.037), tissue-level strength (p=0.006), and tissue-level post-yield strain (p=0.012) than the OLM group. Probing the morphological and compositional relationships among the three groups, both OHM and OLM exhibited increased PEN content (p<0.001, p=0.008 respectively) and increased Log(cortical pore score) relative to YNG (p=0.003, p<0.001 respectively). Compared to the OHM group, the OLM also exhibited increased marrow area (p=0.049), water content (p=0.048), and decreased Ct.TMD (p=0.005). The key traits that were unique to the OLM group compared to YNG were decreased Ct.TMD (p<0.001) and increased Log(porosity) (p=0.002). There were many properties that differed between the younger and older groups, but not all were associated with reduced mechanical properties, highlighting the relative importance of certain age-related traits such as porosity, Ct.TMD, water content, and marrow area that were unique to the OLM group. Overall, this work supports the hypothesis that there are subgroups of men showing different strength-decline trajectories with aging and establishes a basis for refining our understanding of which age-related changes are directly contributing to decreased strength.

Impact of Fracture Line Width on Radiographic Diagnosis of Vertical Root Fractures: Analysis of the Generalised Estimating Equation Model.

To undertake a joint analysis of the influence of fracture width, dental thickness and distance of the fracture from the cortical bone on the radiographic diagnosis of vertical root fractures. Thirty-six uniradicular bovine teeth were endodontically treated and distributed into three groups according to the remaining root dentine thickness: 1.2 mm, 1.5 mm and 1.8 mm. Each group comprised 12 teeth, six with vertical root fracture and six without. Scanning electron microscopy (SEM) images of the fractured tooth groups were obtained and the fracture lines were measured. All specimens were inserted into bone defects created in bovine ribs, at different distances from the external cortical bone. Digital periapical radiographs were randomly evaluated by three blinded examiners (presence or absence of fractures). The specificity for periapical radiography was found to be 89% and the accuracy rate was 57.4%. The mixed-model regression using the generalised estimating equation (GEE) model showed that the width of the fracture line and the thickness of the dental remnant play an important role in radiographic detection of vertical root fractures. There is a lower chance of correct diagnosis with fracture line widths < 0.2 mm (odds ratio [OR] 0.294, 95% confidence interval [CI] 0.103 to 0.836; P = 0.022) and tooth thicknesses < 1.2 mm (OR 0.342, 95% CI 0.157 to 0.747; P = 0.007). Fracture line widths < 0.2 mm and smaller root thicknesses lead to a less accurate diagnosis of vertical root fractures on periapical radiographs.

Current Concepts in Pediatric Pelvic Ring Fractures: A Narrative Review

Trauma is still the leading cause of death in children. Post mortem studies have shown a high incidence and a high rate of deaths related to pelvic fractures and associated injuries. The pelvic ring in children has characteristics that differentiate it from the adult. The bone tissue is more elastic and is covered with a thick periosteum. Elasticity mainly translates into plastic deformity when it is impacted. Overall, lesions tend to be more stable as the relatively thick periosteum limits bone breakdown. As a result of this elasticity, the intrapelvic organs are more vulnerable and injuries can occur in the absence of fractures. High energy is required to produce a fracture and this energy can be transferred to the pelvic organs. Minimally displaced fractures may be the result of high energy trauma with a significant risk of further intrapelvic and intra-abdominal injury. This leads to a relatively high incidence of pelvic and abdominal organ injuries associated with stable fractures. A complete lesion of the pelvic ring anteriorly or posteriorly or a complex pelvic lesion is a high risk factor for morbidity and mortality. Treatment in the pediatric patient with a pelvic fracture has historically been guided by concepts that have become established in adults. The main parameters in the decision making process are hemodynamic stability and the degree of mechanical instability of the pelvis. The purpose of this review is to report current knowledge on pelvic ring fractures with a particular focus on their management and treatment.

Reactive fluid flow guided by grain-scale equilibrium reactions during eclogitization of dry crustal rocks

Fluid flow in crystalline rocks in the absence of fractures or ductile shear zones dominantly occurs by grain boundary diffusion, as it is faster than volume diffusion. It is, however, unclear how reactive fluid flow is guided through such pathways. We present a microstructural, mineral chemical, and thermodynamic analysis of a static fluid-driven reaction from dry granulite to ‘wet’ eclogite. Fluid infiltration resulted in re-equilibration at eclogite-facies conditions, indicating that the granulitic protolith was out of equilibrium, but unable to adjust to changing P–T conditions. The transformation occurred in three steps: (1) initial hydration along plagioclase grain boundaries, (2) complete breakdown of plagioclase and hydration along phase boundaries between plagioclase and garnet/clinopyroxene, and (3) re-equilibration of the rock to an eclogite-facies mineral assemblage. Thermodynamic modelling of local compositions reveals that this reaction sequence is proportional to the local decrease of the Gibbs free energy calculated for ‘dry’ and ‘wet’ cases. These energy differences result in increased net reaction rates and the reactions that result in the largest decrease of the Gibbs free energy occur first. In addition, these reactions result in a local volume decrease leading to porosity formation; i.e., pathways for new fluid to enter the reaction site thus controlling net fluid flow. Element transport to and from the reaction sites only occurs if it is energetically beneficial, and enough transport agent is available. Reactive fluid flow during static re-equilibration of nominally impermeable rocks is thus guided by differences in the energy budget of the local equilibrium domains.

Treatment of Degenerative Lumbar Spondylolisthesis by Tongdu Bushen Acupuncture, Intradermal Acupuncture, and Moxibustion Integrated Therapy Combined with Core Muscle Training Program: Study Protocol for a Randomized Controlled Clinical Trial.

Background Degenerative lumbar spondylolisthesis (DLS), one of the most common causes of low back pain, is defined as the displacement of a vertebral body over the lower vertebral body with degenerative changes and the absence of fracture or defect in the vertebral ring. This disease is a common and frequently occurring disease. Currently, there are many clinical treatment methods, but there is no specific method, and most of them have the characteristics of slow effect and easy recurrence. Objective The objective of this study is to summarize and analyze the effects of treatment of degenerative lumbar spondylolisthesis by Tongdu Bushen acupuncture, intradermal acupuncture, and moxibustion integrated therapy combined with core muscle training program (CMT) on the improvement of pain degree and dysfunction index, as well as the gait characteristics. Methods 120 patients with DLS will be recruited and randomly divided into two groups using electroacupuncture combined with the CMT group as the control group. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedic Association score (JOA) will be used for evaluation. The spatiotemporal and kinematics parameters in gait analysis, as well as the ability of lumbar muscle contraction, fatigue resistance, relaxation, and coordination of lumbar muscle in surface electromyography (sEMG), will be used as objective observation indexes to observe the effectiveness of Tongdu Bushen acupuncture, intradermal acupuncture, and moxibustion integrated therapy combined with CMT. Discussion. Tongdu Bushen acupuncture, intradermal acupuncture, and moxibustion integrated therapy is a traditional Chinese medicine treatment for DLS. Our results will provide evidence to determine whether the integrated therapy can effectively treat DLS, as well as its advantages and safety, and lay a foundation for further research. This trial is registered with ChiCTR2100050409.

Bayesian Deterministic Inversion Based on the Exact Reflection Coefficients Equations of Transversely Isotropic Media With a Vertical Symmetry Axis

Unconventional reservoirs usually have strong anisotropy. Generally, they can be regarded as transversely isotropic media with a vertical symmetry axis [(VTI) media] in the absence of fractures. Therefore, it is of great significance to develop high-accuracy inversion method for VTI media. The three elastic parameters and two Thomsen anisotropy parameters of VTI media are usually obtained by indirect calculation or inversion methods based on the approximate formulas. However, the cumulative errors caused by indirect calculation and low calculation accuracy of the approximate formulas limit the estimation accuracy of these parameters. In this article, we propose a new method based on the exact reflection coefficients equations (ERCEs) of VTI media to improve the inversion accuracy of these elastic and anisotropy parameters. The new method adopts the Bayesian deterministic inversion (BDI) strategy to solve the inversion problem, which becomes highly nonlinear when using the ERCEs. We analyze the feasibility of the new method using the residual function maps (RFMs) and eigenvalue analysis of Hessian matrix. The analysis results show that the BDI strategy can well solve a series of problems brought by the ERCEs for nonlinear inversion, such as strong nonlinearity and more target parameters need to invert. Both synthetic and field data examples show that the proposed method can accurately estimate the elastic and anisotropy parameters, which verifies the feasibility and effectiveness of the method.

Comparative analysis of functional outcome between operative and conservative treatment for closed, displaced, intra- articular fractures of the Calcaneum, a randomized study

Background: Calcaneum fracture is one of the more common fractures causing significant morbidity to the patients, so debate continues for choice of management of calcaneal fractures, between operative and conservative management. The aim of this study was to compare the outcomes of operative management and conservative management in closed, displaced, intra- articular fractures of the calcaneum. Materials and Methods: Thirty patients with thirty-two displaced intra-articular calcaneal fractures were selected during July 2019 to June 2020 with taking inclusive and exclusive criteria into consideration and randomly divided into surgical and non-surgical groups. First group of patients was managed with operative technique. Patients in other group were treated with closed reduction and cast immobilization using the Omoto technique. The observations in both the groups were compared and analysed. Results: The difference between the outcomes of surgical treatment and nonsurgical methods that were significant were noted. The fracture union occurred between 12 -16 weeks and no case of non-union has been reported. Some of the patients had reported with wound related complications and were managed with higher antibiotics and regular antiseptic dressings. The functional assessment of patients during follow ups has indicated that 87.6% patients of the operated group has good to excellent outcomes while 87.55% of conservatively managed patients have good to fair outcome. Conclusion: Operative management for closed displaced, intra- articular calcaneal fractures in absence of high grade osteoporosis, fracture comminution, and associated morbidity may be the preferred method of treatment.