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Trochanteric Buttress Plate Combined with Proximal Femoral Nail for Unstable Intertrochanteric Fractures. [Innovative Technique] 被引量:3
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作者 Shashikant Basavraj Ganjale Wasudeo M. Gadegone Pradeep Kothadia 《Open Journal of Orthopedics》 2018年第6期235-247,共13页
Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric commin... Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric comminution and coronal split. This study is to evaluate the results of Trochanteric Buttress Plate (TBP) combined with PFN in an unstable IT fractures for buttressing lateral wall and reinforcing fixation. Materials and Methods: We carried out a consecutive study of 32 patients of Unstable intertrochanteric fracture femur with lateral wall comminution. It was studied at Ashwini Sahakari Rugnalaya and Sanshodhan Kendra Solapur India and Government medical college Chandrapur India from April-2015 to December-2017 using innovative Trochanteric buttress plate along with PFN. Eighteen male and fourteen female in the age group of 55 to 80 years were included in the study. There were 26 cases of A3 and six cases of A2 were fixed by PFN combined with trochanteric buttress plate to augment the comminuted lateral wall. Results: The bone healing is observed in all the cases in the mean period of 12.6 weeks. Four patients developed complications, including lateral migration of neck screws (n = 2), superficial infection (n = 2). Patients were followed up for a mean of 10.6 months. At the end of follow-up the Salvati and Wilson hip function was 36 (out of 40) in 87.5% of patients [twenty eight patients]. The clinical, radiological and functional outcomes were found to be satisfactory. Conclusion: The stabilization of lateral trochanteric wall with trochanteric buttress plate restores anatomy, increases the stability of construct and prevents inherent complication of screw migration and cutout. 展开更多
关键词 Trochanteric BUTTRESS Plate LATERAL Wall Comminution of GREATER Trochanter UNSTABLE Trochanteric Fracture SCREW Migration CUT Out of SCREW
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The Radial Nerve Entrapment in Pediatric Extension-Type Supracondylar Humeral Fractures. About Two Cases Reports
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作者 Amadou N. Kassé Malick Diallo +4 位作者 Souleymane Diao Mohamed Tall Babacar Thiam Jean Claude F. Sané Mouhamadou H. Sy 《Open Journal of Orthopedics》 2016年第3期52-57,共6页
Radial nerve injuries in displaced extension-type supracondylar humeral fractures in children are well known. Entrapment in fracture of radial nerve is uncommon and rarely evocated in literature. We report two similar... Radial nerve injuries in displaced extension-type supracondylar humeral fractures in children are well known. Entrapment in fracture of radial nerve is uncommon and rarely evocated in literature. We report two similar cases in the mechanism of injury, the clinical findings and the treatment and propose therapeutic guidelines. 展开更多
关键词 ENTRAPMENT Radial Nerve Exploration Supracondylar Humeral fractures
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Advancements in the diagnosis and management of complex trimalleolar ankle fractures:A comprehensive review
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作者 Lorenzo Lucchetta Giampiero Mastroeni +3 位作者 Giuseppe Rinonapoli Auro Caraffa Saran Singh Gill Valerio Pace 《World Journal of Orthopedics》 2026年第1期1-12,共12页
Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current ev... Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes. 展开更多
关键词 Trimalleolar ankle fractures Complex ankle fractures Trimalleolar fractures Fibula fractures Tibia fractures
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Investigation of strata fractures during longwall mining:Original introscopic probe and image analysis methods
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作者 Mateusz Kudasik Marta Skiba +3 位作者 Jerzy Krawczyk Janusz Kruczkowski Mariusz Młynarczuk Norbert Skoczylas 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1049-1059,共11页
The research presented in this paper aimed to analyze the evolution of fractures in strata in relation to the progress of longwall mining.To achieve this objective,an introscopic probe equipped with a highresolution c... The research presented in this paper aimed to analyze the evolution of fractures in strata in relation to the progress of longwall mining.To achieve this objective,an introscopic probe equipped with a highresolution camera was developed,along with additional equipment that enables continuous recording of the internal surfaces of drainage boreholes exceeding 100 m in depth.The probe was utilized to test two methane drainage boreholes in the Z-3b longwall,which operates within the 501/3 coal seam of the Jankowice mine in Poland.Automatic image analysis methods were applied to evaluate the recorded images,based on a newly developed classificationsystem for fractures categorized by size and number.The results were compared with an analysis of changes in the methane capture rate from the drainage boreholes,which correlated with longwall mining progress.A strong correlation was observed between the number of fractures and the lithology of the strata layers.The largest number of fractures and their evolution were recorded in the coal layers,followed by the shale layers,while the sandstone layers exhibited the least number of fractures.Based on parallel measurements of the methane capture rate from the drainage boreholes during the progress of longwall mining,the extent of the strata's fracture zone was determined to range from 6 m to 36 m.Within the fracture zone,the strata are highly fractured,which leads to an increase in methane emissions through seepage and diffusion processes. 展开更多
关键词 COAL METHANE Coal fracture Introscopic probe Fracture zone
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Experimental Study of Sand Transport Assisted by Self-Suspended Proppant in Complex Fractures
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作者 Yang Zhang Xiaoping Yang +3 位作者 Yalan Zhang Mingzhe Han Jiayi Sun Zhengsheng Xia 《Fluid Dynamics & Materials Processing》 2026年第1期138-153,共16页
Self-suspended proppants,which enable clear-water fracturing,represent a promising new class of materials for reservoir stimulation.Given the economic limitations associated with their exclusive use,this study investi... Self-suspended proppants,which enable clear-water fracturing,represent a promising new class of materials for reservoir stimulation.Given the economic limitations associated with their exclusive use,this study investigates proppant transport behavior in hybrid systems combining self-suspended proppants with conventional 40/70 mesh quartz sand at various mixing ratios.A dedicated experimental apparatus was developed to replicate field-relevant complex fracture networks,consisting of a main fracture and two branching fractures with different deflection angles.Using this system,sand bank formation and proppant distribution were examined for both conventional quartz sand fracturing and fracturing augmented with self-suspended proppants.The effects of slurry discharge volume,proppant mixing ratio,sand ratio,and injection location of the self-suspended proppant on transport and placement behavior were systematically analyzed.According to the results,the incorporation of self-suspended proppants markedly enhances the proppant-carrying capacity of the slurry and substantially modifies sand bank morphology.Increasing the discharge volume raises the inlet slope angle and promotes greater proppant penetration into branch fractures.The proportion of self-suspended proppant governs slurry viscoelasticity and,consequently,proppant settling behavior.As the fraction of self-suspended proppant decreases,the equilibrium height of the sand bank increases,while the proppant mass fraction within branch fractures exhibits a non-monotonic response,initially decreasing and then increasing.Variations in sand ratio alter both overall proppant concentration and the self-suspended proppant-to-water ratio,thereby modulating slurry rheology and influencing proppant placement.In addition,changes in injection location affect near-wellbore vortex structures,leading to distinct sand bank morphologies. 展开更多
关键词 Unconventional oil and gas clearwater fracturing self-suspended proppant complex fractures assisted sand transportation
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Numerical Simulation of Cross-Layer Propagation Mechanisms for Hydraulic Fractures in Deep Coal-Rock Formations
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作者 Zhirong Jin Xiaorui Hou +4 位作者 Yanrong Ge Tiankui Guo Ming Chen Shuyi Li Tianyu Niu 《Energy Engineering》 2026年第2期369-391,共23页
Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane(CBM)development,where the mechanical properties of gangue layers exert a significant control on fracture propagati... Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane(CBM)development,where the mechanical properties of gangue layers exert a significant control on fracture propagation behavior.To address the unclear mechanisms governing fracture penetration across coal-gangue interfaces,this study employs the Continuum-Discontinuum Element Method(CDEM)to simulate and analyze the vertical propagation of hydraulic fractures initiating within coal seams,based on geomechanical parameters derived from the deep Benxi Formation coal seams in the southeastern Ordos Basin.The investigation systematically examines the influence of geological and operational parameters on cross-interfacial fracture growth.Results demonstrate that vertical stress difference,elastic modulus contrast between coal and gangue layers,interfacial stress differential,and interfacial cohesion at coal-gangue interfaces are critical factors governing hydraulic fracture penetration through these interfaces.High vertical stress differences(>3 MPa)inhibit interfacial dilation,promoting predominant crosslayer fracture propagation.Reduced interfacial stress contrasts and enhanced interfacial cohesion facilitate fracture penetration across interfaces.Furthermore,smaller elastic modulus contrasts between coal and gangue correlate with increased interfacial aperture.Finally,lower injection rates effectively suppress vertical fracture propagation in deep coal reservoirs.This study elucidates the characteristics and mechanisms governing cross-layer fracture propagation in coal–rock composites with interbedded partings,and delineates the dynamic evolution laws and dominant controlling factors involved.Thefindings provide critical theoretical insights for the optimization of fracture design and the efficient development of deep coalbed methane reservoirs. 展开更多
关键词 Deep coal-rock formations cross-layer fracturing fluid-solid coupling fracture propagation behavior numerical simulation
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Biocompatibility and healing patterns in experimentally induced canine tibial fractures using Pedicle screw- Rod external fixation
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作者 Mohammad Mahdi Gooran Ramin Mazaheri-Khameneh +1 位作者 Seyed Mohammad Hashemi-Asl Rahim Hobbenaghi 《Animal Models and Experimental Medicine》 2026年第1期31-40,共10页
Background:Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure.Pedicle screws are primarily designed for internal fixation in spi... Background:Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure.Pedicle screws are primarily designed for internal fixation in spinal procedures.A key objec-tive of many orthopedic studies is to assess the biocompatibility of implants with bone and adjacent soft tissue.This study aims to evaluate the biocompatibility and effects of the Pedicle screw-Rod configuration as a novel external fixation method in canine tibial osteotomy.Methods:With ethics approval,eight healthy,intact male dogs,aged 10-12 months and weighing between 20 and 22 kg,underwent a minimally invasive medial tibial approach for surgical fixation of tibial osteotomy using a Pedicle screw-Rod configu-ration.Postoperative evaluations included ultrasound assessments at the osteotomy site and histological evaluations at the bone-screw interface.Results:B-mode ultrasound evaluation indicated healing progress at all osteotomy sites.The color Doppler examination revealed an initial increase in signals in the sur-rounding soft tissue during the first 4 weeks post-operation,followed by a decrease in signals within the adjacent soft tissue between the 5th and 8th weeks.During this latter period,the signals were primarily concentrated on the bone surface and the callus.The bone-screw interface at various screw sites exhibited similar histological changes,indicating effective integration of the newly formed woven bone into the screw threads.Conclusions:Fixation of non-articular tibial osteotomy with Pedicle screw-Rod con-figuration resulted in secondary bone healing,characterized by abundant callus for-mation and neovascularization.This implant demonstrated favorable biocompatibility with bone and surrounding soft tissue,without significant complications. 展开更多
关键词 dog fracture NEOVASCULARIZATION OSTEOINTEGRATION Pedicle screw-Rod TIBIA
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Clinical outcomes of humeral shaft fractures managed with intramedullary K-wires:A closed reduction approach
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作者 Mohammad Adham Abdulsamad Turki S AlMugren +6 位作者 Abdullah I Saeed Waleed A Alrogy Linah D Alanazi Ohud M Alsaqer Faisal T Alanbar Abdulrahman H Alfarraj Ziad A Aljaafri 《World Journal of Orthopedics》 2026年第1期57-66,共10页
BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges f... BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges from nonoperative methods to surgical interventions such as intramedullary K-wires,which promote faster rehabilitation and improved elbow mobility.AIM To evaluate the outcomes of managing humeral shaft fractures using closed reduction and internal fixation with flexible intramedullary K-wires.METHODS This was a retrospective cohort study analyzing the medical records of patients with humeral shaft fractures managed with flexible intramedullary K-wires at King Abdulaziz Medical City,using non-random sampling and descriptive analysis for outcome evaluation.RESULTS This study assessed the clinical outcomes of 20 patients treated for humeral shaft fractures with intramedullary K-wires.Patients were predominantly male(n=16,80%),had an average age of 39.2 years,and a mean body mass index of 29.5 kg/m^(2).The fractures most frequently occurred in the middle third of the humerus(n=14,70%),with oblique fractures being the most common type(n=7,35%).All surgeries used general anesthesia and a posterior approach,with no intraoperative complications reported.Postoperatively,all patients achieved clinical and radiological union(n=20,100%),and the majority(n=13,65%)reached an elbow range of motion from 0 to 150 degrees.CONCLUSION These results suggest that intramedullary K-wire fixation may be an effective option for treating humeral shaft fractures,with favorable outcomes in range of motion recovery,fracture union,and a low rate of intraoperative complications. 展开更多
关键词 Humeral shaft fractures Flexible intramedullary K-wires Clinical outcomes Range of motion Surgical management
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Research on the Efficacy of Autologous Periosteum Graft Combined with PRP in the Treatment of Long Bone Fractures in the Extremities
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作者 Xiang Chen 《Journal of Clinical and Nursing Research》 2026年第1期323-330,共8页
Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with ... Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with long bone fractures in the extremities admitted to Santai Hospital Affiliated to North Sichuan Medical College from January 2023 to January 2025 were included,including cases of upper extremity forearm fractures and lower extremity femoral and tibial fractures.The patients were evenly divided using a random number table,with the control group undergoing open reduction and internal fixation(ORIF)combined with autologous periosteum graft,and the observation group undergoing ORIF,autologous periosteum graft,and PRP injection.Surgical indicators,complication rates,excellent fracture healing rates,functional satisfaction,and joint range of motion were compared between the two groups.Results:The surgical indicators in the observation group were similar to those in the control group(p>0.05).The complication rate in the observation group was lower than that in the control group,while the excellent fracture healing rate and functional satisfaction were higher in the observation group(p<0.05).Conclusion:Autologous periosteum graft combined with PRP technology is safe and reliable for the treatment of long bone fractures in the extremities,with satisfactory clinical outcomes. 展开更多
关键词 Periosteum graft Long bones of the extremities PRP Complication rate Fracture healing
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Effect of dominant fractures on triaxial behavior of 3D-printed rock analogs with internal fracture networks
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作者 Lishuai Jiang Pimao Li +3 位作者 Xin He Yang Zhao Quansen Wu Ye Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1390-1412,共23页
Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly a... Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly affecting the macromechanical properties and failure modes.These fractures affect the instability and failure of the surrounding rock,significantlyimpacting the overall stability of engineering structures.Herein,sand-powder three-dimensional(3D)printing technology was used to prepare rock-like specimens with internal fracture networks.Triaxial compression testing,post-failure fracture mapping,and fractal dimension analysis of the fracture surfaces were conducted to investigate the effects of dominant fracture angles on the strength and deformation of rocks with internal fracture networks under triaxial stress.The results indicate that the dominant fracture angle has a pronounced effect on the mechanical behavior of rock.With increasing angle,both compressive strength and elastic modulus exhibit an initial decline followed by an increase.Moreover,higher confiningpressure significantlyimproves the compressive strength of fractured rock.This enhancement weakens as the confiningpressure further increases.Moreover,with increasing confiningpressure,the differences between the maximum and minimum values of elastic moduli and lateral strain ratios in fractured rock gradually decrease.Thus,the impact of the dominant fracture angle on rock mass deformation decreases with increasing confiningpressure.This research elucidates the effects of dominant fracture angles on the mechanical and failure properties of complex fractured rock masses and the influenceof the confiningpressure on these relationships.It provides valuable theoretical insights and practical guidance for stability analyses in engineering rock masses. 展开更多
关键词 Sand powder three-dimensional(3D) printing Internal fracture networks Triaxial compression Rock mechanics Fractal dimension
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A bio-healing method for underground long rock fractures with high bridging rate
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作者 Qi-Chen Dai Xiao-Hua Pan +1 位作者 Chao-Sheng Tang Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1359-1367,共9页
One of the key challenges for underground rock reservoirs is ensuring prevention of the unwanted fluid leakage through rock fracture networks during their service life.Microbial-induced calcium carbonate precipitation... One of the key challenges for underground rock reservoirs is ensuring prevention of the unwanted fluid leakage through rock fracture networks during their service life.Microbial-induced calcium carbonate precipitation(MICP)technology has emerged as a promising bio-healing method for rock fractures with small apertures.In this study,a new“three-stage”injection strategy-based MICP(TS-MICP)bio-healing method was proposed,aiming to achieve a“three-high”performance that includes high bridging rate,high mechanical strength,and high homogeneity.A series of meter-scale rock fracture models were prepared to conduct TS-MICP grouting tests.Compared with the traditional injection strategy-based biohealing methods,the TS-MICP method significantly improved the bridging rate(32.1%e89.5%),mechanical properties(0.138e1.023 MPa),and homogeneity of CaCO_(3)precipitation(334.4%).Additionally,it achieved a higher material utilization rate(1.72 times higher),reducing the consumption of cementation solution(CS)by 258.8%,thereby demonstrating greater potential for field applications.The underlying mechanism for achieving high bridging rate and high homogeneity in CaCO_(3)precipitation can be attributed to the synergistic effects of the coupling injection strategy,which optimizes the advantages at each stage.In stage I,under the influence of gravity,the rapid flocculation and hydrogen bonding interactions of organic matter lead to formation of the dense and high-strength CaCO_(3)precipitation at the bottom using a low-concentration bacterial suspension(BS).This process establishes bridging steps along the wall sides for subsequent uniform CaCO_(3)precipitation.In stage II,concentrated BS is utilized to produce looser CaCO_(3)flocculation,which precipitates uniformly on the pre-existing bridging steps.In stage III,a two-step injection strategy was employed to reinforce the loose CaCO_(3)crystals formed in stages I and II,and finally forms a strong bridging effect with“three-high”performance. 展开更多
关键词 Microbial-induced calcium carbonate precipitation(MICP)healing Meter-scale fracture Three-stage injection strategy High bridging rate
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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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Experimental and numerical studies on propagation behavior between hydraulic fractures and pre-existing fractures under prepulse combined hydraulic fracturing 被引量:1
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作者 Chao Wei Liyuan Yu +2 位作者 Shentao Geng Zichen Yuan Yubo Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2879-2892,共14页
Prepulse combined hydraulic fracturing facilitates the development of fracture networks by integrating prepulse hydraulic loading with conventional hydraulic fracturing.The formation mechanisms of fracture networks be... Prepulse combined hydraulic fracturing facilitates the development of fracture networks by integrating prepulse hydraulic loading with conventional hydraulic fracturing.The formation mechanisms of fracture networks between hydraulic and pre-existing fractures under different prepulse loading parameters remain unclear.This research investigates the impact of prepulse loading parameters,including the prepulse loading number ratio(C),prepulse loading stress ratio(S),and prepulse loading frequency(f),on the formation of fracture networks between hydraulic and pre-existing fractures,using both experimental and numerical methods.The results suggest that low prepulse loading stress ratios and high prepulse loading number ratios are advantageous loading modes.Multiple hydraulic fractures are generated in the specimen under the advantageous loading modes,facilitating the development of a complex fracture network.Fatigue damage occurs in the specimen at the prepulse loading stage.The high water pressure at the secondary conventional hydraulic fracturing promotes the growth of hydraulic fractures along the damage zones.This allows the hydraulic fractures to propagate deeply and interact with pre-existing fractures.Under advantageous loading conditions,multiple hydraulic fractures can extend to pre-existing fractures,and these hydraulic fractures penetrate or propagate along pre-existing fractures.Especially when the approach angle is large,the damage range in the specimen during the prepulse loading stage increases,resulting in the formation of more hydraulic fractures. 展开更多
关键词 Prepulse combined hydraulic fracturing Prepulse loading parameters Fracture networks Fracture propagation Pre-existing fracture
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Revisiting the normal stiffness–permeability relations for shale fractures under true triaxial stress 被引量:1
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作者 Fudong Li Derek Elsworth +6 位作者 Xia-Ting Feng Tianyu Chen Jun Zhao Yingchun Li Jianyu Zhang Qiong Wu Guanglei Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5001-5017,共17页
Understanding the relationship between normal stiffness and permeability in rock fractures under high and true-triaxial in situ stress conditions is critical to assess hydro-mechanical coupling in the Earth's crus... Understanding the relationship between normal stiffness and permeability in rock fractures under high and true-triaxial in situ stress conditions is critical to assess hydro-mechanical coupling in the Earth's crust.Previous data on stiffness–permeability relations are measured under uniaxial stress states as well as under normal stress.However,many projects involve faulted formations with complex three-dimensional(3D)stress states or significant changes to the original stress state.We rectified this by following the permeability evolution using a true-triaxial stress-permeability apparatus as well as independently applying a spectrum of triaxial stresses from low to high.The relationship between permeability and fracture normal stiffness was quantified using constraints based on the principle of virtual work.The impacts of fracture-lateral and fracture-normal stresses on permeability and normal stiffness evolution were measured.It was found that permeability decreases with increasing fracture-lateral and fracture-normal stresses as a result of Poisson confinement,independent of the orientation of the fracture relative to the stresses.The lateral stresses dominated the evolution of normal stiffness at lower normal stresses(σ_(3)=10 MPa)and played a supplementary role at higher normal stresses(σ_(3)>10 MPa).Moreover,correlations between the evolution of permeability and normal stiffness were extended beyond the low-stiffness,high-permeability region to the high-stiffness,low-permeability region under high fracture-lateral stresses(10–80 MPa)with fracture-normal stress(10–50 MPa)conditions.Again,high lateral stresses further confined the fracture and therefore reduced permeability and increased normal stiffness,which exceeded the previous reported stiffness under no lateral stress conditions.This process enabled us to identify a fundamental change in the flow regime from multi-channel to isolated channelized flow.These results provide important characterizations of fracture permeability in the deep crust,including recovery from deep shale-gas reservoirs. 展开更多
关键词 Fracture permeability Deformation Fracture normal stiffness True-triaxial stress Principle of virtual work
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Developing a nomogram for postoperative delirium in elderly patients with hip fractures 被引量:1
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作者 Liang Li Wei-Wei Sheng +5 位作者 Li-Juan Song Shuai Cheng En-Gang Cui Yong-Bing Zhang Xue-Zhong Yu Yan-Li Liu 《World Journal of Psychiatry》 2025年第3期142-155,共14页
BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term outco... BACKGROUND Postoperative delirium(POD)is a prevalent complication,particularly in elderly patients with hip fractures(HFs).It significantly affects recovery,length of hospital stay,healthcare costs,and long-term outcomes.Existing studies have investigated risk factors for POD,but most are limited by single-factor analyses or small sample sizes.This study systematically determines independent risk factors using large-scale data and machine learning techniques and develops a validated nomogram model to support early prediction and management of POD.AIM To investigate POD incidence in elderly patients with HF and the independent risk factors,according to which a nomogram prediction model was developed and validated.METHODS This retrospective study included elderly patients with HF who were surgically treated in Dongying People’sHospital from April 2018 to April 2022. The endpoint event includes POD. They were categorized into themodeling and validation cohorts in a 7:3 ratio by randomization. Both cohorts were further classified into thedelirium and normal (non-delirium) groups according to the presence or absence of the endpoint event. Theincidence of POD was calculated, and logistic multivariate analysis was conducted to determine the independentrisk factors. The calibration curve and the Hosmer-Lemeshow test as well as the net benefit threshold probabilityinterval by the decision curve were utilized to statistically validate the accuracy of the nomogram predictionmodel, developed according to each factor’s influence intensity.RESULTSThis study included 532 elderly patients with HF, with an overall POD incidence of 14.85%. The comparison ofbaseline data with perioperative indicators revealed statistical differences in age (P < 0.001), number of comorbidities(P = 0.042), American Society of Anesthesiologists grading (P = 0.004), preoperative red blood cell(RBC) count (P < 0.001), preoperative albumin (P < 0.001), preoperative hemoglobin (P < 0.001), preoperativeplatelet count (P < 0.001), intraoperative blood loss (P < 0.001), RBC transfusion of ≥ 2 units (P = 0.001), andpostoperative intensive care unit care (P < 0.001) between the delirium and non-delirium groups. The participantswere randomized to a training group (n = 372) and a validation group (n = 160). A score-risk nomogram predictionmodel was developed after screening key POD features using Lasso regression, support vector machine, and therandom forest method. The nomogram showed excellent discriminatory capacity with area under the curve of0.833 [95% confidence interval (CI) interval: 0.774-0.888] in the training group and 0.850 (95%CI: 0.718-0.982) in thevalidation group. Calibration curves demonstrated good agreement between predicted and actual probabilities,and decision curve analysis confirmed clinical net benefits within risk thresholds of 0%-30% and 0%-36%, respectively.The model has strong accuracy and clinical utility for predicting the risk of POD.CONCLUSIONThis study reveals cognitive impairment history, American Society of Anesthesiologists grade of > 2, RBCtransfusion of ≥ 2 units, postoperative intensive care unit care, and preoperative hemoglobin level as independentrisk factors for POD in elderly patients with HF. The developed nomogram model demonstrates excellent accuracyand stability in predicting the risk of POD, which is recommended to be applied in clinical practice to optimizepostoperative management and reduce delirium incidence. 展开更多
关键词 Hip fracture Postoperative delirium NOMOGRAM Risk factor Retrospective study
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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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Effect of Screw Distribution on Stability and Interfragmentary Strain of Lower Tibial Fractures:A Finite Element Analysis
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作者 Huan Su Huan Xiao +3 位作者 Jian-jun Zhou Fang Lei Liang Liang De-wei Wang 《Current Medical Science》 2025年第5期1254-1264,共11页
Objective The aim of this study was to explore the influence of working length(determined by the screw position)on the stiffness and interfragmentary strain(IFS)of femoral locking compression plate(LCP)external fixato... Objective The aim of this study was to explore the influence of working length(determined by the screw position)on the stiffness and interfragmentary strain(IFS)of femoral locking compression plate(LCP)external fixators for lower tibial fractures under full weight-bearing conditions,with the goal of providing a reference basis for clinical applications.Methods Finite element analysis software was used to construct a model of a lower tibial fracture with external femoral LCP fixation.The models were divided into four groups according to the different working lengths(external femoral locking plate fixation 1[EF1],EF2,EF3,and EF4).Stress distribution clouds,fracture end displacements,stiffness and IFS were tested for each model group at different loads.Results Compared with those in the EF1 group,the stiffnesses in the EF2,EF3,and EF4 groups decreased by 28%,31%,and 37%,respectively,under axial compression loading.Compared with those in the EF1 group,the stiffnesses in the EF2,EF3,and EF4 groups decreased by 19%,33%,and 35%,respectively,under axial torsion loading.Compared with those in the EF1 group,the stiffnesses in the EF2,EF3,and EF4 groups decreased by 32%,33%,and 35%,respectively,under a three-point bending load.The IFS of the four finite element models increased with the working length of the plate,with EF1(76%)<EF2(107%)<EF3(110%)<EF4(122%).Finite element analysis revealed that under full weight-bearing conditions,the structural stiffness of the femoral LCP external fixator decreased with increasing working length,leading to an increase in the IFS,which resulted in an IFS that exceeded the ideal range required for secondary healing.Conclusion For unstable lower tibial fractures,screws in the femoral LCP external fixator should be placed as close to the fracture end as possible to increase stability and promote fracture healing. 展开更多
关键词 Locking compression plate Working length Lower tibial fractures Distal tibial fractures External fixator Finite element analysis BIOMECHANICS Interfragmentary strain Screw distribution Screw configuration Fracture healing
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Characteristics and distribution patterns of volcanic fractures in the Chaganhua Subsag of the Songliao Basin,China
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作者 Li Ning Shan Xuan-long +5 位作者 Yi Jian Li Zhong-bo Cao Kai-fang Tian Jun Shi Yun-qian Leng Qing-lei 《Applied Geophysics》 2025年第4期1003-1018,1493,共17页
Fractures are critical control factors in volcanic reservoirs.Thus,studies on the prediction and distribution patterns of volcanic fractures are crucial for oil and gas exploration and development.Although considerabl... Fractures are critical control factors in volcanic reservoirs.Thus,studies on the prediction and distribution patterns of volcanic fractures are crucial for oil and gas exploration and development.Although considerable research has been conducted on volcanic fractures,targeted research on the spatial distribution patterns of fracture development remains limited in the literature.Two eruption modes,subaqueous eruption and subaerial eruption,have been identified in the Chaganhua subsag of the Songliao Basin,where gas resources have been discovered.Studying the differences in volcanic fracture development is highly important for understanding the law of oil and gas enrichment in volcanic reservoirs.On the basis of thin sections,cores,electrical imaging logs,and other data obtained from boreholes of subaqueous volcanic eruptions in the Songnan fault depression,we describe the characteristics of drilled fractures in detail and use 3D seismic data to extract intrinsic coherence,ant bodies,and Fourier series to extend the azimuthal anisotropic P-wave reflection coefficient,thereby predicting the spatial distribution of fractures at different scales.Moreover,through statistical analysis of quantitative evaluation indicators,such as fracture density and fracture development rate in different drilling wells,combined with the spatial distribution patterns of the predicted fractures,we compared and analyzed the relationships between the distributions of fractures and volcanic institutions,lithology,and volcanic facies.Results indicate that fractures are more developed in volcanic edifices located closer to faults.Considerable differences in fracture development are observed among lithofacies of volcanic rocks.Near faults,effusion facies,explosive facies and external clastic pyroclastic sedimentary subfacies are favorable for fracture development.This research provides a reference for investigating volcanic rock fractures of the same origins worldwide. 展开更多
关键词 Subaqueous eruption Chaganhua area Volcanic rock Fracture prediction Fourier series Volcanic facies Fracture density Fracture development rate
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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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Osteosarcopenia and geriatric hip fractures:Current concepts
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作者 Theodoros Tosounidis Lefteris Manouras Byron Chalidis 《World Journal of Orthopedics》 2025年第3期35-40,共6页
According to World Health Organization,one in six people will be older than 60 by 2030.The rising life expectancy is anticipated to contribute to a subsequent increase of geriatric fractures worldwide.Osteosarcopenia,... According to World Health Organization,one in six people will be older than 60 by 2030.The rising life expectancy is anticipated to contribute to a subsequent increase of geriatric fractures worldwide.Osteosarcopenia,which is the coexistence of osteoporosis and sarcopenia,greatly affects older people.Recent studies have tried to identify the prevalence of osteosarcopenia in older populations as well as its correlation with fragility fractures such as hip fractures.The latter pose a major burden on both health loss and costs worldwide.Increasing amount of evidence suggests that osteosarcopenia in patients with hip fractures contributes to higher rates of mortality and complications.At the same time,research focuses on the molecular basis of the interplay between osteoporosis and sarcopenia by utilizing genomic or proteomic approaches.These promising studies could reveal potential preventive or diagnostic biomarkers to optimize the management of osteosarcopenia in hip fractures patients.The fact that bones and muscle can also function as endocrine organs further highlights the complex relationship between osteoporosis and sarcopenia,underscoring the need for a better understanding of the role of myokines and osteokines in osteosarcopenia.Finally,the impact of osteosarcopenia on pain management and rehabilitation after hip fracture surgery,requires further assessment. 展开更多
关键词 Osteosarcopenia Hip fracture Fragility fracture MORTALITY RNA-sequencing PROTEOMICS Muscle-bone crosstalk
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