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Role of post-operative X-rays in distal-radius fractures among pediatric patients 被引量:1
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作者 Ammar K Alomran Bandar A Alzahrani +4 位作者 Dana S Alamoud Layan S Alsultan Meshail M AlSaud Raneem G Althobaiti Badriah S Alruwaili 《World Journal of Orthopedics》 2025年第5期51-60,共10页
BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appea... BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures. 展开更多
关键词 X-RAY Distal radius fractures PEDIATRICS ORTHOPEDIC fractures
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Functional outcomes of radial head arthroplasty in Mason type III and IV fractures
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作者 Shikhar Bindal Harshaan Singh Pooni +1 位作者 Rajnish Garg Deepak Jain 《World Journal of Orthopedics》 2025年第6期56-66,共11页
BACKGROUND Radial head fractures constitute approximately one-third of all elbow fractures,significantly impacting the young and active population.While open reduction and internal fixation is the preferred treatment ... BACKGROUND Radial head fractures constitute approximately one-third of all elbow fractures,significantly impacting the young and active population.While open reduction and internal fixation is the preferred treatment for displaced fractures,its high complication rate in comminuted fractures has led to the increasing use of radial head arthroplasty(RHA).RHA provides improved functional outcomes with fewer complications,yet its long-term efficacy remains a topic of debate.AIM To evaluate the functional outcomes of patients undergoing RHA with a modular metallic prosthesis for comminuted Mason type III and IV radial head fractures.METHODS A prospective and retrospective hospital-based study was conducted at Dayanand Medical College and Hospital,Ludhiana over 32 months(January 2021-August 2023).A total of 26 patients with Mason type III and IV fractures were included,with six retrospective and 20 prospective cases.Functional outcomes were assessed using the Mayo Elbow Performance Score(MEPS),elbow range of motion,pain via Visual Analog Scale,and activities of daily living at immediate postoperative,three-month,and six-month follow-ups.RESULTS MEPS at 6 months follow up for 4 cases(15.38%)had good scores,and 22 cases(84.62%)had excellent scores,with a mean±SD of 97.31±6.67.Comparisons showed significant improvement from immediate post-operative to 3 months(P<0.0001),from immediate post-operative to 6 months(P<0.0001),and between 3 months and 6 months(P<0.0001).None of the patients had elbow instability after radial head replacement and 22 cases(84.62%)had no complications,while 3 cases(11.54%)had a stiff elbow,and 1 case(3.85%)had heterotopic ossification.CONCLUSION RHA is an effective treatment for comminuted radial head fractures,providing stable elbow function with minimal complications. 展开更多
关键词 Radial head arthroplasty Radial head replacement Mason classification Mason type III and IV fractures Elbow fractures Functional outcomes Mayo elbow performance score Elbow dislocation
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Comparative analysis of elbow radiographic measurements in patients with supracondylar humerus fractures and healthy controls
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作者 Nuri KÜlgen Batuhan Gencer Özgür Doğan 《World Journal of Orthopedics》 2025年第5期38-43,共6页
BACKGROUND Supracondylar humeral fractures(SCHF)are the second most common fractures in childhood and can lead to short-and long-term complications.Despite their prevalence,the anatomical factors that predispose child... BACKGROUND Supracondylar humeral fractures(SCHF)are the second most common fractures in childhood and can lead to short-and long-term complications.Despite their prevalence,the anatomical factors that predispose children to SCHF remain unclear.This study aimed to determine whether there are significant morpho-logical differences in the elbow by comparing the radiographic angular measure-ments of the contralateral elbows of patients with SCHF to those of patients with distal radius fractures(DRF)and a healthy control group.We sought to explore if these morphological variations contribute to the occurrence of SCHF.Radiographs of 78 SCHF patients were analyzed for angular measurements of the contralateral elbow.Two control groups were used:98 healthy children and 40 patients with DRF.Angular measurements included Baumann angle(BA),hu-meroulnar angle(HUA),humerus metaphysis-diaphysis angle(HMDA),humerus shaft-condylar angle(HSCA),and lateral capitellohumeral angle.Only BA,HUA,and HMDA were measured in the DRF group.Statistical analysis was performed to compare differences among groups.RESULTS Significant differences were found in elbow measurements between SCHF and control groups(P<0.05).However,the mean values for all groups fell within the ranges described in the literature.CONCLUSION While statistically significant differences were found in elbow morphology between SCHF patients and controls,these differences don't translate into clinically meaningful morphological deviations. 展开更多
关键词 Pediatric elbow Supracondylar humerus fractures Distal radius fractures Elbow morphology Baumann angle
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Correlation between anxiety, depression, and social stress in young patients with thoracolumbar spine fractures
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作者 Bo Wang Da Shi +1 位作者 Yin-Di Sun Bo Dong 《World Journal of Psychiatry》 SCIE 2025年第1期83-92,共10页
BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily comb... BACKGROUND Traumatic injuries,such as falling,car accidents,and crushing mostly cause spinal fractures in young and middle-aged people,and>50%of them are thoracolumbar fractures.This kind of fracture is easily combined with serious injuries to peripheral nerves and soft tissues,which causes paralysis of the lower limbs if there is no timely rehabilitation treatment.Young patients with thoracolumbar fractures find it difficult to recover after the operation,and they are prone to depression,low self-esteem,and other negative emotions.AIM To investigate the association between anxiety,depression,and social stress in young patients with thoracolumbar spine fractures and the effect on rehabilitation outcomes.METHODS This study retrospectively analyzed 100 patients admitted to the orthopedic department of Honghui Hospital,Xi’an Jiaotong University who underwent thoracolumbar spine fracture surgery from January 2022 to June 2023.The general data of the patients were assessed with the Hamilton anxiety scale(HAMA),Hamilton depression scale(HAMD),life events scale,and social support rating scale(SSRS)to identify the correlation between anxiety,depression scores,and social stress and social support.The Japanese Orthopedic Association(JOA)was utilized to evaluate the rehabilitation outcomes of the patients and to analyze the effects of anxiety and depression scores on rehabilitation.RESULTS According to the scores of HAMD and HAMA in all patients,the prevalence of depression in patients was 39%(39/100),and the prevalence of anxiety was 49%(49/100).Patients were categorized into non-depression(n=61)and depression(n=39),non-anxiety(n=51),and anxiety(n=49)groups.Statistically significant differences in gender,occupation,Pittsburgh Sleep Quality Index(PSQI)score,and monthly family income were observed between the non-depression and depression groups(P<0.05).A significant difference in occupation and PSQI score was found between the non-anxiety and anxiety groups.Both depression(r=0.207,P=0.038)and anxiety scores(r=0.473,P<0.001)were significantly and positively correlated with negative life events.The difference in negative life event scores as well as SSRS total and item scores was statist-ically significant between patients in the non-depression and depression groups(P<0.05).The difference between the non-anxiety and anxiety groups was statistically significant(P<0.05)in the negative life event scores as well as the total SSRS scores.Additionally,JOA scores were significantly lower in both anxious and depressed patients.CONCLUSION Young patients with thoracolumbar fractures are prone to anxiety and depression.Patients’anxiety and depression are closely associated with social pressure,which reduces the life pressure of young patients with thoracolumbar fractures,enhances social support,and improves the psychology of anxiety and depression.,which affects patients’recovery. 展开更多
关键词 Patients with thoracolumbar fractures ANXIETY DEPRESSION Social pressure Social support
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Analysis of Hydraulic Fracture Network Morphology in Stimulated Coal Reservoirs with Pre-Existing Natural Fractures
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作者 Weiping Ouyang Luoyi Huang +1 位作者 Jinghua Liu Hongzhong Zhang 《Energy Engineering》 2025年第4期1491-1509,共19页
Hydraulic fracturing is a crucial technique for efficient development of coal reservoirs.Coal rocks typically contain a high density of natural fractures,which serve as conduits for fracturing fluid.Upon injection,the... Hydraulic fracturing is a crucial technique for efficient development of coal reservoirs.Coal rocks typically contain a high density of natural fractures,which serve as conduits for fracturing fluid.Upon injection,the fluid infiltrates these natural fractures and leaks out,resulting in complex fracture morphology.The prediction of hydraulic fracture network propagation for coal reservoirs has important practical significance for evaluating hydraulic fracturing.This study proposes a novel inversion method for predicting fracture networks in coal reservoirs,explicitly considering the distribution of natural fractures.The method incorporates three distinct natural fracture opening modes and employs a fractal probability function to constrain fracture propagationmorphology.Based on thismethod,the study compares hydraulic fracture networkmorphologies in coal reservoirs with andwithout the presence of natural fractures.Theresults showthatwhile both reservoir types exhibitmulti-branch fracture networks,reservoirs containing natural fractures demonstrate greater branching and a larger stimulated reservoir volume(SRV).Additionally,the study employs a fractal dimension calculation method to quantitatively describe the geometric distribution characteristics of fractures.The analysis reveals that the geometry and distribution of natural fractures,as well as reservoir geological parameters,significantly influence the fracture networkmorphology and fractal dimension.The contact angle between natural and hydraulic fractures affects propagation direction;specifically,when the contact angle isπ/2,the fractal dimension of the hydraulic fracture network is maximized.Moreover,smaller lengths and spacings of natural fracture led to higher fractal dimensions,which can significantly increase the SRV.The proposed method offers an effective tool for evaluating the hydraulic fracturing of coal reservoirs. 展开更多
关键词 Coal reservoirs hydraulic fracturing natural fractures inversion and evaluation fracturing fluid flow fractal dimension
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Prophylactic fixation in elderly fractures: Preventive breakthrough or unnecessary intervention?
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作者 Mohamed Sameer Sathish Muthu Srujun Vadranapu 《World Journal of Orthopedics》 2025年第11期7-15,共9页
Prophylactic fixation(ProFix)of the proximal femur in elderly patients with osteoporosis presents a forward-thinking approach to preventing debilitating fractures and their associated complications.By addressing fract... Prophylactic fixation(ProFix)of the proximal femur in elderly patients with osteoporosis presents a forward-thinking approach to preventing debilitating fractures and their associated complications.By addressing fracture risk before an injury occurs,ProFix has the potential to enhance patient outcomes,promote long-term mobility,and reduce healthcare costs.Early intervention in individuals at high risk can significantly lower hospital admissions,shorten recovery periods,and preserve independence,mitigating challenges such as chronic pain and reduced life expectancy.Given the high prevalence of undiagnosed osteoporosis,prioritising early risk assessment and targeted prevention is essential.Advancements in minimally invasive surgical techniques and safer anaesthesia methods further support ProFix as a feasible and effective strategy to decrease fracturerelated morbidity,improve overall patient well-being,and optimise the use of healthcare resources.This opinion review details the evidence supporting this concept,its efficacy,the challenges in its implementation,and a strategic plan for future implementation. 展开更多
关键词 Prophylactic fixation Osteoporotic fractures Proximal femur Fracture prevention Elderly patients Bone health Predictive analytics
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Effect of Spatial Variability in the Geometry of Fractures on Granite Slope Stability
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作者 Lin Jia Jing-Sen Cai +3 位作者 Li Wu Tian-Chyi Jim Yeh E-Chuan Yan Yi Du 《Journal of Earth Science》 2025年第5期1923-1935,共13页
A DFN-DEC(discrete fracture network-distinct element code)method based on the MATLAB platform is developed to generate heterogeneous DFN.Subsequently,the effects of the spatial variability(the meanμand the standard d... A DFN-DEC(discrete fracture network-distinct element code)method based on the MATLAB platform is developed to generate heterogeneous DFN.Subsequently,the effects of the spatial variability(the meanμand the standard deviationσ)of the geometric properties(i.e.,the fracture dip D,the trace length T and the spacing S)of both the gently-dipping(denoted with 1)and the steeply-dipping(denoted with 2)fractures on the stability of granite slope are investigated.Results indicate that the proposed DFN-DEC method is robust,generating fracture networks that resemble reality.In addition,the spatial variability of fracture geometry,influencing the structure of granite slope,plays a significant role in slope stability.The mean stability of the slope decreases with the increase ofμ_(D_(1))(the mean of gently-dipping fracture dip),σ_(D_(2))(the mean of steeply-dipping fracture dip),μ_(T_(1))(the mean of gently-dipping fracture trace length),μ_(T_(2))(the mean of steeply-dipping fracture trace length),σ_(T_(1))(the standard deviation of gently-dipping fracture trace length),σ_(T_(2))(the standard deviation of steeply-dipping fracture trace length),and the decrease ofσ_(D_(1))(the standard deviation of gently-dipping fracture dip),μ_(D_(2))(the standard deviation of steeply-dipping fracture dip),μ_(S_(1))(the mean of gently-dipping fracture spacing)andμ_(S_(2))(the mean of steeply-dipping fracture spacing).Among them,μ_(T_(1)),μ_(D_(1))andμ_(S_(1))have the major impact.When the fracture spacing is large,the variability in the fracture geometry becomes less relevant to slope stability.When within some ranges of the fracture spacing,the spatial varying of dips can increase the slope stability by forming an interlaced structure.The results also show that the effects of the variability of trace length on slope stability depend on the variability of dip.These findings highlight the importance of spatial variability in the geometry of fractures to rock slope stability analysis. 展开更多
关键词 slope stability spatial variability geometry of fractures steep-gentle combined fracture model DFN-DEC method engineering geology
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A 3D framework for geological media with multiple intersected fractures:Coupled Darcy flow and Fickian diffusion
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作者 Luyu Wang Weizhong Chen Cornelis Vuik 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6293-6307,共15页
Despite extensive research on computational geomechanics and fluid dynamics,accurately simulating convection-diffusion(CD)processes in complex fractured systems remains a significant challenge.This study develops a 3D... Despite extensive research on computational geomechanics and fluid dynamics,accurately simulating convection-diffusion(CD)processes in complex fractured systems remains a significant challenge.This study develops a 3D numerical framework for modelling CD processes in fractured geological media.The framework integrates Darcy's law and Fick's law,considering flux interactions between the matrix and fractures.The meshing strategy generates high-quality grids even in scenarios involving intersecting fractures.Then,a unified numerical scheme for solving the CD system is proposed.The novelties of this work include:(1)The proposed framework enables effective simulation of 3D fractured media,including more complex fractured vuggy media;(2)The numerical method precisely discretizes the CD terms in governing equations;(3)A Non-Orthogonal Correction(NOC)method,combined with an adaptive time integration scheme,is proposed for eliminating errors induced by skewed grids;and(4)The effects of fracture patterns and heterogeneity on flow are thoroughly analysed.The proposed method is validated through benchmark tests,demonstrating the superiority of the NOC method compared to classical methods.Further analysis reveals the evolution characteristics of pressure and concentration,offering insights into the effects of fracture patterns and heterogeneity on flow and diffusion processes. 展开更多
关键词 Fractured rock masses 3D multiple fractures CONVECTION-DIFFUSION Darcy flow Fickian diffusion
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Dynamic slip behavior and off-fault damage of tension-induced fractures constrained by different grain sizes in granite
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作者 Feili Wang Fanzhen Meng +4 位作者 Muzi Li Qijin Cai Zhufeng Yue Zhanguo Xiu Zaiquan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1539-1554,共16页
The mineralogy and texture of granite have been found to have a pronounced effect on its mechanical behavior.However,the precise manner in which the texture of granite affects the shear behavior of fractures remains e... The mineralogy and texture of granite have been found to have a pronounced effect on its mechanical behavior.However,the precise manner in which the texture of granite affects the shear behavior of fractures remains enigmatic.In this study,fine-grained granite(FG)and coarse-grained granite(CG)were used to create tensile fractures with surface roughness(i.e.joint roughness coefficient(JRC))within the range of 5.48-8.34 and 12.68-16.5,respectively.The pre-fractured specimens were then subjected to direct shear tests under normal stresses of 1-30 MPa.The results reveal that shear strengths are smaller and stick-slip behaviors are more intense for FG fractures than for CG fractures,which is attributed to the different conditions of the shear surface constrained by the grain size.The smaller grain size in FG contributes to the smoother fracture surface and lower shear strength.The negative friction rate parameter a-b for both CG and FG fractures and the larger shear stiffness for FG than for CG fractures can account for the more intense stick-slip behaviors in FG fractures.The relative crack density for the post-shear CG fractures is greater than that of the FG fractures under the same normal stress,both of which decrease with the distance away from the shear surface following the power law.Moreover,the damage of CG fracture extends to a larger extent beneath the surface compared with the FG fracture.Our findings demonstrate that the grain size of the host rock exerts a significant influence on the fracture roughness,and thus should be incorporated into the assessment of fault slip behavior to better understand the role of mineralogy and texture in seismic activities. 展开更多
关键词 Granite fractures Mineral grain size ROUGHNESS STICK-SLIP Microcracking behavior Crack density
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Characteristics,controlling factors and mechanisms of natural fractures formation in lacustrine shale oil reservoirs:The Chang 7 member in Ordos Basin,China
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作者 Xiao-Yu Du Zhi-Jun Jin +6 位作者 Lian-Bo Zeng Guo-Ping Liu Shi-Xiang Li Mehdi Ostadhassan Xin-Ping Liang Guan-Ping Wang Guo-Qing Lu 《Petroleum Science》 2025年第4期1391-1406,共16页
Lacustrine shale oil reservoirs of the Upper Triassic Chang 7 Member in the Ordos Basin have demonstrated significant potential for hydrocarbon resources.Natural fractures play a crucial role in hydrocarbon enrichment... Lacustrine shale oil reservoirs of the Upper Triassic Chang 7 Member in the Ordos Basin have demonstrated significant potential for hydrocarbon resources.Natural fractures play a crucial role in hydrocarbon enrichment and production.Outcrops,cores,borehole image logs,thin sections,and FE-SEM images were used to investigate the types and characteristics of natural fractures in the Chang 7 Member.The factors controlling fracture development and the mechanisms of bedding-parallel fracture formation were revealed by integrating TOC analysis,XRD analysis,and rock pyrolysis.Results show that natural fractures in the study area include high-angle tectonic fractures and nearly horizontal bedding-parallel fractures.Brittle minerals and bed thickness control the occurrence and attributes of tectonic fractures.High TOC content and thermal maturity positively affect the development of bedding-parallel fractures,formed through the conversion of organic matter to hydrocarbons or the smectite-to-illite transformation.Additionally,the dominant orientations of tectonic fractures intersect the present-day maximum horizontal principal stress at a small angle,resulting in large apertures and good effectiveness.Bedding-parallel fractures contribute to enhance porosity and provide favorable pathways for lateral hydrocarbon migration.Collectively,this study could provide valuable insights for finding promising exploration areas in lacustrine shale oil reservoirs in the Ordos Basin and worldwide. 展开更多
关键词 Natural fractures MECHANISMS Lacustrine shale Chang 7 Ordos Basin
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Psychological impact of minimally invasive approaches in the management of pelvic fractures with lumbosacral plexus injury
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作者 Osvaldo Mazza Giuseppe Marano Marianna Mazza 《World Journal of Psychiatry》 2025年第8期424-428,共5页
Pelvic fractures are rare but severe injuries that severely affect patients’quality of life.Treatment of these fractures often involves invasive approaches with high risk of injuries to nervous structures,particularl... Pelvic fractures are rare but severe injuries that severely affect patients’quality of life.Treatment of these fractures often involves invasive approaches with high risk of injuries to nervous structures,particularly lumbosacral plexus.The introduction of minimally invasive surgical approaches,such as the lateral rectus approach,not only contributes to preserving lumbar plexus integrity in operated patients but also positively impacts their psychological well-being.Patients treated by surgical reduction of pelvic fractures with lumbosacral plexus injury often experience states of anxiety and depression.The lateral rectus approach is associated with lower levels of anxiety and depression compared to more invasive surgical techniques used for similar fractures. 展开更多
关键词 Pelvic fractures ANXIETY DEPRESSION Lumbosacral plexus Minimally invasive approach
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Osteoporosis and fragility fractures in patients with acromegaly: A two-center cross-sectional study
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作者 Mauricio Alvarez Juliana Rincon +5 位作者 Maria Mercedes Ulloa Oswaldo Rincon Liliana Mejia Alejandra Alvarado Andres Pereira Mónica Bernal 《World Journal of Orthopedics》 2025年第11期83-91,共9页
BACKGROUND Acromegaly,a disease of excess growth hormone,is known to alter bone structure and increase the risk of osteoporosis and fractures.This study aimed to assess the prevalence of vertebral,non-vertebral,and hi... BACKGROUND Acromegaly,a disease of excess growth hormone,is known to alter bone structure and increase the risk of osteoporosis and fractures.This study aimed to assess the prevalence of vertebral,non-vertebral,and hip fragility fractures,as well as osteoporosis,in a cohort of patients with acromegaly.AIM To assess the prevalence of vertebral fragility fractures,non-vertebral fragility fractures,hip fragility fractures,and osteoporosis in patients diagnosed with acromegaly.METHODS Data were collected on age,sex,body mass index(BMI),time from diagnosis of acromegaly,insulin-like growth factor(IGF-1)levels,disease control,pharmacological management,risk factors for osteoporosis,vertebral fragility fractures,non-vertebral fragility fractures,hip fragility fractures,and osteoporosis.RESULTS A total of 124 patients with acromegaly were included(67 men and 57 women).The mean age at diagnosis was 44±12 years;the mean time from diagnosis was 12±8 years;and the mean BMI was 27±4 kg/m².Fragility fractures were found in 27 patients(21%).There were no significant differences in the presence of osteoporosis or fragility fractures according to age,sex,BMI,duration of acrom egaly,or IGF-1 levels at diagnosis.A higher percentage of patients with osteoporosis were treated with somatostatin analogs compared to those without osteoporosis(46%vs 15%;P<0.05).CONCLUSION A high prevalence of osteoporosis and fragility fractures was found in patients with acromegaly,regardless of age,sex,BMI,time from diagnosis,IGF-1 levels,and disease control.More patients with osteoporosis were treated with somatostatin analogs compared to those without osteoporosis.Taken together,our results suggest that the severity of the disease and the need for second-line therapies,may be associated with the increased risk of osteoporosis. 展开更多
关键词 ACROMEGALY Bone density Spinal fractures OSTEOPOROSIS Pituitary gland Growth hormone-secreting pituitary adenoma
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Response characteristics of shear waves scattered by fractures with borehole observation system
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作者 Peng Liu Hua-Jun Fan +4 位作者 Meng-Sheng Zhang Zhen Li Jing-Wei Jiang Yuan Gao Ke-Wen Wang 《Petroleum Science》 2025年第5期1912-1928,共17页
Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as ... Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as fracture length and dip angle are the focus of geophysical work.In borehole observation system,the short distance between fractures and detectors leads to weak attenuation of elastic wave energy,and high-frequency source makes it easier to identify small-scale fractures.Compared to traditional monopole logging methods,dipole logging method has advantage of exciting pure shear waves sensitive to fractures,so its application is becoming increasingly widespread.However,since the reflected shear waves and scattered shear waves of fractures correspond to different fracture properties,how to distinguish and analyze these two kinds of waves is crucial for accurately characterizing the fracture parameters.To address this issue,numerical simulation of wave responses by a single fracture near a borehole in rock formation is performed,and the generation mechanism and characteristics of shear waves scattered by fractures are investigated.It is found that when the dip angle of the fracture surpasses a critical threshold,the S-wave will propagate to both endpoints of the fracture and generate scattered S-waves,resulting in two distinct scattered wave packets on the received waveform.When the polarization direction of the acoustic source is parallel to the strike of the fracture,the scattered SH-waves always have larger amplitude than the scattered SV-waves regardless of changing the fracture dip angle.Unlike SV-waves,the SH-waves scattered by the fracture do not have any mode conversion.Additionally,propagation of S-waves to a short length fracture can induce dipole mode vibration of the fracture within a wide frequency range.The phenomena of shear waves reflected and scattered by the fracture are further illustrated and verified by two field examples,thus showing the potential of scattered waves for fracture evaluation and characterization with borehole observation system. 展开更多
关键词 Numerical modeling Wave scattering Shear wave fractures Borehole observation system
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Anisotropy of non-Darcian flow in rock fractures subjected to cyclic shearing
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作者 Zihao Sun Liangchao Zou +3 位作者 Liangqing Wang Jia-Qing Zhou Zhen Cui Qiong Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6373-6387,共15页
Non-Darcian flow in rock fractures exhibits significant anisotropic characteristics,which can be affected by mechanical processes,such as cyclic shearing.Understanding the evolution of anisotropic nonDarcian flow is c... Non-Darcian flow in rock fractures exhibits significant anisotropic characteristics,which can be affected by mechanical processes,such as cyclic shearing.Understanding the evolution of anisotropic nonDarcian flow is crucial for characterizing groundwater flow and mass/heat transport in fractured rock masses.In this study,we conducted experiments on non-Darcian flow in single rough fractures under cyclic shearing conditions,aiming to analyze the anisotropic evolution of inertial permeability and viscous permeability.We established quantitative characterization models for the two types of permeability.First,we conducted cyclic shearing experiments on four sets of 24 rough rock fractures,investigating their shear characteristics.Then,we performed 480 non-Darcian flow experiments to analyze the anisotropic evolution of viscous permeability and inertial permeability of these rock fractures.The results showed that viscous permeability exhibited significant differences only in the orthogonal direction,while inertial permeability exhibited differences in both orthogonal and opposite directions.With increase in the shear cycles,the differences in the orthogonal direction gradually increased,while those in opposite direction gradually decreased.Finally,we established characterization equations for the two permeabilities based on the proposed directional geometric parameters and validated the performance of these equations with experimental data.These findings are useful for the quantitative characterization of the evolution of non-Darcian flow in fractures under dynamic loading conditions. 展开更多
关键词 Rock fractures Cyclic shearing Viscous permeability Inertial permeability Rock anisotropy Non-darcian flow
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Formation Mechanisms and Distribution Patterns of Fractures in Shale Reservoirs:A Case Study of the Lucaogou Formation,Jimsar Sag,Junggar Basin
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作者 Xiangye Kong Xingjian Wang +6 位作者 Zhiwu Li Peng Zhu Yixin Dong Qun Luo Zhiqi Zhong Zhanbo Liu Jie Tan 《Journal of Earth Science》 2025年第5期2373-2379,共7页
0 INTRODUCTION Shale oil has become a significant component of unconventional oil and gas exploration worldwide,dramatically transforming the global energy landscape over the past two decades(Xu et al.,2024;Guo et al.... 0 INTRODUCTION Shale oil has become a significant component of unconventional oil and gas exploration worldwide,dramatically transforming the global energy landscape over the past two decades(Xu et al.,2024;Guo et al.,2023;Wan et al.,2023;Zou et al.,2020).The successful commercial development of shale oil resources in North America has triggered a global surge in unconventional petroleum exploration,with many countries now actively pursuing their own shale resource development programs(Yang and Jin,2019). 展开更多
关键词 unconventional oil gas exploration unconventional petroleum explorationwith Lucaogou formation shale resource shale oil formation mechanisms shale reservoirs fractures
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Novel handheld pelvic alignment guide for hollow screw fixation in osteoporotic pelvic fragility fractures
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作者 Yuan Wang Zhen-Yu Tan +4 位作者 Jie-Ming He Yue-Xia Shu Zhen Pan De-Gang Zhu Jia Wang 《World Journal of Orthopedics》 2025年第7期72-81,共10页
BACKGROUND Retrograde pubic ramus screw placement is an effective technique but requires substantial surgical expertise and specialized equipment.The management of osteoporotic anterior pelvic ring injuries remains ch... BACKGROUND Retrograde pubic ramus screw placement is an effective technique but requires substantial surgical expertise and specialized equipment.The management of osteoporotic anterior pelvic ring injuries remains challenging due to technical difficulties and a high risk of complications.AIM To introduce a novel and simplified surgical approach that utilizes a custom-designed handheld pelvic alignment guide(HPAG)in combination with a 6.0 mm hollow screw,aiming to enhance the accuracy,efficiency,and safety of retrograde pubic ramus screw fixation in osteoporotic pelvic fragility fractures.METHODS The HPAG and 6.0 mm hollow screw were employed during surgical treatment.A 2.0-3.0 cm incision was made to expose the optimal screw entry point.Intraop-erative pelvic inlet and obturator oblique views were used to monitor fracture reduction and guide screw insertion.Clinical outcomes and fracture reduction quality were evaluated using Matta,visual analog scale,and Majeed scores during follow-ups.A representative case is presented to demonstrate the surgical procedure in detail.RESULTS No perioperative complications were observed.The mean operative time was 35.2±6.97 minutes,with a screw insertion time of 7.25±1.86 minutes,an average incision length of 2.8±0.67 cm,and mean blood loss of 43.25±15.64 mL.At one-year follow-up,seven patients achieved excellent Majeed scores and three achieved good scores.CONCLUSION No perioperative complications were observed.The mean operative time was 35.2±6.97 minutes,with a screw insertion time of 7.25±1.86 minutes,an average incision length of 2.8±0.67 cm,and mean blood loss of 43.25±15.64 mL.At one-year follow-up,seven patients achieved excellent Majeed scores and three achieved good scores. 展开更多
关键词 Pelvic fragility fractures Anterior pelvic ring OSTEOPOROSIS Hollow screw Minimally invasive
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Accuracy of artificial intelligence in prediction of osteoporotic fractures in comparison with dual-energy X-ray absorptiometry and the Fracture Risk Assessment Tool: A systematic review
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作者 Mir Sadat-Ali Bandar A Alzahrani +4 位作者 Turki S Alqahtani Musaad A Alotaibi Abdallah M Alhalafi Ahmed A Alsousi Abdullah M Alasiri 《World Journal of Orthopedics》 2025年第4期51-57,共7页
BACKGROUND Osteoporotic fractures,whether due to postmenopausal or senile causes,impose a significant financial burden on developing countries and diminish quality of life.Recent advancements in artificial intelligenc... BACKGROUND Osteoporotic fractures,whether due to postmenopausal or senile causes,impose a significant financial burden on developing countries and diminish quality of life.Recent advancements in artificial intelligence(AI)algorithms have demonstrated immense potential in predicting osteoporotic fractures.AIM To assess and compare the efficacy of AI models against dual-energy X-ray absorptiometry(DXA)and the Fracture Risk Assessment Tool(FRAX)in predicting fragility fractures.METHODS We conducted a literature search in English using electronic databases,including PubMed,Web of Science,and Scopus,for studies published until May 2024.The keywords employed were fragility fractures,osteoporosis,AI,deep learning,machine learning,and convolutional neural network.The inclusion criteria for selecting publications were based on studies involving patients with proximal femur and vertebral column fractures due to osteoporosis,utilizing AI algorithms,and analyzing the site of fracture and accuracy for predicting fracture risk using SPSS version 29(Chicago,IL,United States).RESULTS We identified 156 publications for analysis.After applying our inclusion criteria,24489 patients were analyzed from 13 studies.The mean area under the receiver operating characteristic curve was 0.925±0.69.The mean sensitivity was 68.3%±15.3%,specificity was 85.5%±13.4%,and positive predictive value was 86.5%±6.3%.DXA showed a sensitivity of 37.0% and 74.0%,while FRAX demonstrated a sensitivity of 45.7%and 84.7%.The P value for sensitivity between DXA and AI was<0.0001,while for FRAX it was<0.0001 and 0.2.CONCLUSION This review found that AI is a valuable tool to analyze and identify patients who will suffer from fragility fractures before they occur,demonstrating superiority over DXA and FRAX.Further studies are necessary to be conducted across various centers with diverse population groups,larger datasets,and a longer duration of follow-up to enhance the predictive performance of the AI models before their universal application. 展开更多
关键词 Artificial intelligence OSTEOPOROSIS PREDICTION Fragility fractures
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The threat of hemorrhage from pelvic fractures:Clinicians seeking new solutions based on biomedical Mg implant
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作者 Qinghui Han Xiaonong Zhang +2 位作者 Wenhui Wang Kaiyang Wang Tao Wang 《Journal of Magnesium and Alloys》 2025年第4期1476-1479,共4页
Biodegradable magnesium(Mg)materials offer significant advantages in trauma care due to their degradable nature and superior mechanical properties.This study reports the first successful use of degradable Mg clips in ... Biodegradable magnesium(Mg)materials offer significant advantages in trauma care due to their degradable nature and superior mechanical properties.This study reports the first successful use of degradable Mg clips in damage control surgery for pelvic fractures,addressing challenges associated with severe hemorrhage and high mortality rates(30-70%).A 57-year-old male patient with pelvic fractures and traumatic shock underwent open reduction and internal fixation with Mg clips.At a six-month follow-up,imaging confirmed fracture healing,clip degradation,and no signs of rebleeding or infection,highlighting their effectiveness in precise hemorrhage control.Unlike traditional titanium clips,Mg clips degrade over time,eliminating the need for removal and reducing infection risks.This innovative approach combines Mg clips with conventional gauze packing,offering a more effective and safer alternative for managing pelvic trauma.Future large-scale clinical trials are necessary to validate these findings and establish Mg clips as a global standard for pelvic fracture treatment.Their portability and functionality hold promise for advancing emergency trauma care. 展开更多
关键词 Biodegradable Mg HEMORRHAGE Pelvic fractures Ligation clip
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Natural fractures controlled by strike-slip faults in ultradeep carbonate reservoirs:A case study of the Middle and Lower Ordovician in the Tarim Basin,China
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作者 Dong-Sheng Cao Jun Han +8 位作者 Lian-Bo Zeng Cheng Huang Paul Dirk Bons Guo-Ping Liu Ying-Tao Yao Zhe Mao Wen-Ya Lyu Isaac Naaman Ling-Ping Zeng 《Petroleum Science》 2025年第7期2760-2776,共17页
Natural fractures controlled by faults in ultradeep carbonate strata play substantial roles as both fluid migration channels and storage spaces.However,characterizing the heterogeneous distribution of underground frac... Natural fractures controlled by faults in ultradeep carbonate strata play substantial roles as both fluid migration channels and storage spaces.However,characterizing the heterogeneous distribution of underground fractures within the complex three-dimensional geometry of strike-slip fault zones remains challenging.This study investigates the characteristics of natural fractures controlled by strike-slip faults in the fractured Middle and Lower Ordovician reservoirs of the central and northern Tarim Basin,China.Seismics,cores,and image logs were integrated to quantitatively analyze the intensity and dip angle of natural fractures and findings were verified using published sandbox simulations.The carbonate reservoir contains three main types of natural fractures:tectonic fractures,abnormal high-pressure-related fractures,and stylolites.Strike-slip faults control the distribution and characteristics of tectonic fractures across various scales.Generally,both fracture intensity and porosity exhibit a decreasing trend as the distance from the main fault surface increases.Compared with those in non-stepover zones along a strike-slip fault,natural fractures and faults in stepover zones are more developed along the fault strike,with significantly greater development intensity in central stepover regions than that at its two ends.Furthermore,strike-slip faults influence the dip angles of both natural fractures and secondary faults.The proportion of medium-to-low-dip angle fractures and faults in the stepover zone is greater than that in the non-stepover zone.Additionally,the proportion of medium-to low-dip angle fractures and faults in the middle of the stepover is greater than that at both ends.Therefore,strike-slip fault structures control the dip angle of natural fracture and the heterogeneity of secondary fault and fracture intensity.The linking damage zone in the stepover contains a larger volume of fractured rocks,making it a promising petroleum exploration target.The development of stepovers and the orientation of present-day in-situ stress substantially influence the productivity of fractured reservoirs controlled by strike-slip faults.The analysis in this study reveals that reservoir productivity increases as the angle between the strike-slip fault segment and the maximum horizontal principal stress decreases.This study provides valuable insights for quantitatively evaluating fracture heterogeneity in fractured reservoirs and establishing optimized selection criteria for favorable targets in fault-related fractured reservoirs. 展开更多
关键词 Ultradeep carbonate reservoirs Strike-slip fault Natural fractures Fault stepover Tarim Basin
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Influence of Particle Size Distribution on Shear Behavior of Weak Interlayers:Insights from Filled Fractures Shear Tests
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作者 Jiajun Ji Changdong Li +2 位作者 Cheng Dong Wenqiang Chen Bingchen Li 《Journal of Earth Science》 2025年第5期2341-2347,共7页
0 INTRODUCTION During the geological evolution process,tectonic activities coupled with anthropogenic engineering disturbances have collectively contributed to the development of complex fracture-filling networks with... 0 INTRODUCTION During the geological evolution process,tectonic activities coupled with anthropogenic engineering disturbances have collectively contributed to the development of complex fracture-filling networks within rock masses(Feng et al.,2024;Tan et al.,2020;Li et al.,2019).The particle size distribution of infilling materials within fractures is susceptible to multiple controlling factors,including material composition,seepage-induced erosion,and tectonic disturbances(Zhang et al.,2024;Tan et al.,2023). 展开更多
关键词 geological evolution tectonic disturbances zhang weak interlayers infilling materials rock masses feng shear behavior filled fractures anthropogenic engineering disturbances
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