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A segmental defect adaptation of the mouse closed femur fracture model for the analysis of severely impaired bone healing
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作者 Amandeep Kaur Subburaman Mohan Charles H.Rundle 《Animal Models and Experimental Medicine》 CSCD 2020年第2期130-139,共10页
Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone i... Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone injury was adapted from the threepoint bending closed fracture technique in the murine femur.Methods: The mouse femur was surgically stabilized with an intramedullary threaded rod with plastic spacers and the defect adjusted to different sizes. Healing of the different defects was analyzed by radiology and histology to 8 weeks postsurgery. To determine whether this model was effective for evaluating the benefits of molecular therapy, BMP-2 was applied to the defect and healing then examined.Results: Intramedullary spacers were effective in maintaining the defect. Callus bone formation was initiated but was arrested at defect sizes of 2.5 mm and above, with no more progress in callus bone development evident to 8 weeks healing. Cartilage development in a critical size defect attenuated very early in healing without bone development, in contrast to the closed femur fracture healing, where callus cartilage was replaced by bone. BMP-2 therapy promoted osteogenesis of the resident cells of the defect, but there was no further callus development to indicate that healing to pre-surgery bone structure was successful.Conclusions: This segmental defect adaptation of the closed femur fracture model of murine bone repair severely impairs callus development and bone healing, reflecting a challenging bone injury. It is adjustable and can be compared to the closed fracture model to ascertain healing deficiencies and the efficacy of therapeutic approaches. 展开更多
关键词 bone fractures bone morphogenetic protein 2 intramedullary fracture fixation ununited fractures
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Four Pins Assisted Reduction of Complex Segmental Femoral Fractures: a Technique for Closed Reduction 被引量:1
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作者 郑占乐 于贤 +3 位作者 许国强 陈伟 张英泽 焦振清 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第6期912-916,共5页
Complex segmental femoral fractures are usually not amenable to closed reduction. The purpose of this study was to evaluate a series of patients who had undergone four pins assisted reduc- tion and intramedullary nail... Complex segmental femoral fractures are usually not amenable to closed reduction. The purpose of this study was to evaluate a series of patients who had undergone four pins assisted reduc- tion and intramedullary nail fixation to determine the therapeutic effect of this closed reduction tech- nique. Between December 2010 and January 2013, 15 consecutive patients with segmental femoral fractures were treated with four pins assisted reduction at our hospital. The patient was placed in a supine position on a radiolucent fracture table and a. gentle traction was attempted on the limb. Usu- ally, the proximal fracture segment exhibited the typical deformity of flexion, external rotation, and abduction, the middle segment exhibited adduction and distal fracture segment exhibited flexion. Four Schanz pins were placed percutaneously to fix one cortex and did not penetrate into the me- dullary cavity, and the "T" sharp handles were fixed on the Schanz pins. The fragments were then re- duced by reversing the deforming forces for segmental fractures by two assistants~ And then, the re- duction could be easily achieved and intramedullary nail fixation was performed. Radiographs were evaluated for the quality of the reduction and fracture union. Closed reduction was achieved in all pa- tients using the four pins technology. All 15 fractures united uneventfully. No patient had a rotational malunion or limb length discrepancy at the time of the last follow-up. Thirteen of the fifteen (86.7%) patients had anatomic reduction and two of them (13.3%) had minor varus alignment of 3° and 5°. Knee stiffness was Observed in 2 patients and no implant failure was observed. Surgical treatment of complex segmental femoral fractures With four pins assisted reduction and intramedullary nail fixation techniques can result in excellent reductions and a high union rate. 展开更多
关键词 fracture closed reduction segmental fracture FEMUR
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Thrombelastography and color Doppler flow imaging in the perioperative period after closed lower limb fracture
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作者 徐志强 《外科研究与新技术》 2011年第2期114-115,共2页
Objective To observe the changes of thrombelastography (TEG) and color Doppler flow imaging (CDFI) in the perioperative period after closed lower limb fracture.Methods Fasting venous blood samples in the morning from ... Objective To observe the changes of thrombelastography (TEG) and color Doppler flow imaging (CDFI) in the perioperative period after closed lower limb fracture.Methods Fasting venous blood samples in the morning from 11 healthy adults were used 展开更多
关键词 CDFI Thrombelastography and color Doppler flow imaging in the perioperative period after closed lower limb fracture FLOW
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Comparison of three kinds of treatment for pediatric closed femoral shaft fracture
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作者 毛吉刚 《外科研究与新技术》 2005年第3期175-175,共1页
To compare and evaluate 3 kinds of treatments of pediatric closed femoral shaft fractures.Methods Seventy-nine patients were divided into 3 groups and treated using hip spica casting after skeletal traction,unilateral... To compare and evaluate 3 kinds of treatments of pediatric closed femoral shaft fractures.Methods Seventy-nine patients were divided into 3 groups and treated using hip spica casting after skeletal traction,unilateral multifunctional fixation and plate fixation.The result were evaluated according to clinical function,time to union,complications,radiology examination and the economic cost.Results Both time to union and economic cost of the external fixation group were shorter than that of the skeletal traction group and plate fixation group.Conclusion The unilateral multi-functional external fixation is an ideal solution to pediatric close femoral shaft fractures.7 refs,3 tabs. 展开更多
关键词 Comparison of three kinds of treatment for pediatric closed femoral shaft fracture
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Radial nerve recovery following closed nailing of humeral shaft fractures without radial nerve exploration: A retrospective study 被引量:1
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作者 Kuei-Lin Yeh Chen-Kun Liaw +1 位作者 Tai-Yin Wu Chung-Pei Chen 《World Journal of Clinical Cases》 SCIE 2021年第27期8044-8050,共7页
BACKGROUND Radial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures.An antegrade nailing surgical technique is becoming popular for the fixation o... BACKGROUND Radial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures.An antegrade nailing surgical technique is becoming popular for the fixation of these fractures with minimal invasiveness.We analyzed nerve recovery in patients with humeral shaft fracture and radial nerve palsy treated with humeral nail fixation without nerve exploration.AIM To assess the radial nerve recovery rate and time from humeral shaft fracture with surgical treatment using close nailing.METHODS We retrospectively collected data of patients who underwent undergone surgical nail fixation for humeral shaft fractures between October 1,2016,and March 31,2020.Subsequently,we analyzed the primary or secondary radial nerve palsy recovery rate and radial nerve motor function recovery time.RESULTS The study included 70 patients who underwent surgical treatment for closed-or Gustilo type I open humeral shaft fractures using a nail fixation technique without radial nerve exploration.The patients suffered from primary(n=5)and secondary(n=5)radial nerve palsy.A 100%radial nerve recovery rate was achieved.The mean recovery time was 4.3 mo.CONCLUSION The study results indicate full recovery of radial nerve palsies from humeral shaft fracture using close nailing treatment.Surgeons need not be concerned about the occurrence of permanent nerve palsies. 展开更多
关键词 Humeral shaft fracture Radial nerve palsy Close nailing fixation Nerve exploration
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Modified Closed Reduction and Percutaneous Kirschner Wires Internal Fixation for Treatment of Supracondylar Humerus Fractures in Children 被引量:5
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作者 Shu-bin WANG Bin-hui LIN +4 位作者 Wei LIU Guo-jun WEI Zong-guang LI Nai-chun YU Guang-rong JI 《Current Medical Science》 2021年第4期777-781,共5页
Objective Supracondylar humerus fractures are the most frequent fractures of the paediatric elbow.The present study introduced a modified surgical procedure for treatment of supracondylar humerus fractures in children... Objective Supracondylar humerus fractures are the most frequent fractures of the paediatric elbow.The present study introduced a modified surgical procedure for treatment of supracondylar humerus fractures in children.Methods From February 2015 to August 2019,73 patients with Gartland’s type II and III supracondylar fractures were treated with this modified method.Totally,68 of all patients were followed up for 3–12 months(mean 8.25 months).The evaluation results included fracture nonunion,ulnar nerve injury,pin track infection,carrying angle and elbow joint Flynn score.Results The results showed that bone union was observed in all children,one case had an iatrogenic ulnar nerve injury,and the symptoms were completely relieved in 4 months after removing of the medial-side pin.All children had no cubitus varus deformity and no pin track infection,and the rate of satisfactory results according to Flynn’s criteria score was 100%.Conclusion The modified closed reduction and Kirschner wires internal fixation could effectively reduce the rate of open reduction,the risk of iatrogenic ulnar nerve injury,and the incidence of cubitus varus deformity in treatment of supracondylar humerus fractures in children. 展开更多
关键词 supracondylar humerus fractures closed reduction Kirschner wires internal fixation surgical method
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Relationships between gas reservoir and the evolution of stope surrounding rock fracture at the process of mining the closed distance protection layer 被引量:1
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作者 HAO Zhi-yong LIN Bai-quan WU Hai-jin MENG Jie 《Mining Science and Technology》 EI CAS 2009年第5期653-656,共4页
Overburden rock movements and fracture developments occur during mining activities. Consequently, relief gas reservoirs and migration in coal seams being mined as well as in near distant coal seams appear. We consider... Overburden rock movements and fracture developments occur during mining activities. Consequently, relief gas reservoirs and migration in coal seams being mined as well as in near distant coal seams appear. We considered a gas disaster management project and rules on stope relief of gas flows together and explored a gas reservoir and the evolution of stope surrounding rock fractures in the process of mining near distant protective layers by physical simulation, numerical simulation and field testing. Different techniques provide evidence of the rules of interaction of gas reservoirs and the evolution of surrounding rock fractures and are able to find accurately the gas-rich regions around the stope. Finally, we found that these rules can provide a basis for taking measures to prevent gas accidents in the protective layer of the coalface as well as for demonstrating and designing programs to drain high concentrations of gas from the gob. 展开更多
关键词 physical simulation numerical simulation gas reservoir evolution of fractures
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Epidemiological Pattern of Closed Femoral Shaft Fractures in a Regional Tertiary Hospital in Enugu, Nigeria
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作者 E. C. Iyidobi R. T. Ekwunife +3 位作者 U. M. Enweani C. U. Nwadinigwe I. C. Okwesili H. C. Ekwedigwe 《Journal of Biosciences and Medicines》 2019年第5期180-188,共9页
Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point o... Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point of the medial femoral condyle. Femoral shaft fractures often result from high energy forces. These fractures occur mostly among young adults. Objective: This was to determine the epidemiological pattern of closed femoral shaft fractures in a regional tertiary hospital in Enugu, Nigeria. Method: The study was a prospective study over a 12 month period (June 2015-May 2016) at National Orthopaedic Hospital, Enugu. Following ethical approval and written informed consent, patients were consecutively recruited. The patients were clinically and radiographically evaluated at presentation. The diagnosis of closed femoral shaft fractures were made from the physical examination finding of absent open wound communicating with the fracture hematoma in the thigh and anteroposterior (AP) and lateral x-rays of the affected thigh confirming the fracture pattern. The data collected included patients’ demographics, the cause of injury, the side of injury and anatomic site of the injury among other parameters. The data were collected using well designed and structured proforma. Results: A total of 52 femoral shaft fractures in 50 patients were included and analyzed using SPSS version 20.0. The age range of the patients is 18 - 85 years with a median age of 39.1 ± 14.9 years. The most commonly affected age group is 21 - 30 years. There was male preponderance with a male to female ratio of 2.3:1. Majority of the fractures (76.9%) resulted from road traffic crashes most commonly following motor vehicular accident (36.5%). Majority of the fractures (92.3%) are unilateral with right side to left side ratio of 1.2:1. Majority of the patients (51.9%) had Winquist Hansen grade III type of fracture. The most common associated injury is fractures of tibia/fibula followed by fracture of the neck of the ipsilateral femur. All the patients were treated operatively using either locked intramedullary nailing technique or plating technique. Majority of the patients (59.6%) were discharged between 10th and 29th day post-operatively. Conclusion: From the results of this study, it is concluded that most of the closed femoral shaft fractures were caused by high energy trauma from road traffic crashes. It is therefore recommended that proper education of motorists on good use of roads and strict adherence to traffic rules will significantly help in preventing the occurrence of these fractures in our environment. 展开更多
关键词 Epidemiology closed FEMORAL SHAFT fracture
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Treatment of Displaced Mid-Clavicle Fractures by Closed Titanium Elastic Nail
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作者 Hrushikesh Saraf Sarang Kasture 《Surgical Science》 2016年第2期49-53,共5页
Introduction: Recently, intramedullary nailing for displaced middle third fractures of clavicle has received wide attention. Though open nailing has been widely described, closed nailing finds less mention. This paper... Introduction: Recently, intramedullary nailing for displaced middle third fractures of clavicle has received wide attention. Though open nailing has been widely described, closed nailing finds less mention. This paper therefore aims to study the outcome of closed titanium elastic nailing for displaced mid-clavicular fractures. Material and Methods: This was a prospective study of 34 patients with displaced middle third clavicle fracture who underwent closed intramedullary nailing with titanium elastic nail at a tertiary care centre. The operative time, length of incision, time for radiological union, pain and functional outcome after union were noted. Results: The mean operative time was 34.33 mins. The mean time of discharge was 2.25 days. The average time of radiological union was 10.23 weeks. All the patients achieved full, painless range of motion of the ipsilateral shoulder. The average Constant-Murley score at 12 months was 94.28 indicating excellent result. Conclusion: Closed titanium elastic nailing offers a safe and minimally invasive method of fixation for fractures of middle-third clavicle with excellent functional outcome. 展开更多
关键词 CLAVICLE fracture closed Titanium Elastic Nailing
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Meta-analysis of the efficacy of volar plate internal fixation versus closed reduction and external fixation in the treatment of adult distal radius fractures
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作者 CHEN Jian-ge ZHANG Hai-ning +4 位作者 ZHAO Hong-zhou LIU Ming-jun XING Jia-hui WANG Ping WANG Wei-min 《Journal of Hainan Medical University》 CAS 2023年第19期44-56,共13页
Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The ... Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The databases of CNKI,Wanfang,Weipu,Chinese biomedical literature,Pubmed,Embase,and Cochrane Library were retrieved,and the randomized controlled studies that directly compared the efficacy of plate internal fixation and closed reduction external fixation in the treatment of distal radius fractures published publicly from the establishment of the database to April 2023 were collected.The two researchers independently screened the retrieved literature according to the inclusion and exclusion criteria,extracted data,used Cochrane risk bias assessment tool for quality assessment,and used RevMan 5.4 software for meta analysis.Results:A total of 10 randomized controlled trials were included,all of which were in English.There were 1042 patients in total,and 9 of them were rated as low risk.Meta analysis results showed that one year after the treatment of distal radius fracture with volar locking plate internal fixation,DASH score[MD=-5.64,95%CI(-7.21,-4.06),P<0.00001];One year later,PRWE score[MD=-5.90,95%CI(-8.88,-2.92),P=0.001];Palm flexion[MD=5.92,95%CI(1.29,10.55),P=0.01];Pronation[MD=2.48,95%CI(0.59,4.36),P=0.01];Postrotation[MD=4.73,95%CI(2.15,7.31),P=0.0003];Grip strength[MD=0.61,95%CI(0.12,1.10),P=0.02];palmar tilt angle[MD=9.84,95%CI(5.66,14.02),P<0.00001];Radial inclination[MD=4.33,95%CI(2.97,5.69),P<0.00001]was superior to closed reduction plaster or splint external fixation.One year later,the European Five dimensional Health Scale(EQ-5D-5L)score[MD=0.02,95%CI(-0.01,0.05),P=0.27];Back extension[MD=2.22,95%CI(-4.15,8.59),P=0.49];Ulnar deviation[MD=3.49,95%CI(-0.80,7.78),P=0.11];Radial deviation[MD=2.05,95%CI(-2.39,6.50),P=0.37];Ulnar variance[MD=-1.14,95%CI(-3.16,0.88),P=0.27];There was no significant difference in complications[MD=0.77,95%CI(0.54,1.10),P=0.16](P>0.05).Conclusion:Based on the current clinical data,internal fixation with volar locking plate is more conducive to mid-term DASH score and grip strength recovery than closed reduction plaster or splint external fixation,but there is no significant difference in the quality of life and complications of patients.For adult distal radius fractures,surgical indications should be carefully grasped,and non operative treatment should be given priority. 展开更多
关键词 Volar plate Internal fixation closed reduction External fixation PLASTER SPLINT Distal radius fracture Meta analysis
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Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report
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作者 Na Li Yue-Yue Ren +4 位作者 Ying Tang Qi Yang Tian-Tian Meng Song Li Jing Zhang 《World Journal of Clinical Cases》 SCIE 2025年第3期42-49,共8页
BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and te... BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in theliterature.CASE SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical level.After the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival overgrowth.Cone-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival overgrowth.CONCLUSION This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture. 展开更多
关键词 Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report
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Using fracture-based continuum modeling of coupled geomechanical-hydrological processes for numerical simulation of hydraulic fracturing
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作者 Goodluck I.Ofoegbu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1582-1599,共18页
This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fr... This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture caging.The simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(i.e.no re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain grid.The simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density hydraulically.FBCM combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing explicitly.Fractures are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured rock.Simulations are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical orientation.Simulations of a single-well model are used to determine the pattern and spacing for a multiple-well design.The results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than horizontal.If preexisting fractures are steeply dipping or vertical,and considering the same in situ stress condition,well pressurization without fluid permeation appears to be the only practical way to induce new fractures and contain fracturing within the target domain. 展开更多
关键词 Discrete fracture fracture-based continuum modeling fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture
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Management and classification of the fracture of lateral process of talus:An overview and literature update 被引量:1
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作者 Chao-Qun Wang Ulrich Stockle +2 位作者 Sheng-Nan Dong Xu-Gui Li Ze-Xi Ling 《World Journal of Clinical Cases》 SCIE 2024年第15期2487-2498,共12页
Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or misdiagnosed.In recent years,as researchers from all over the world have further deepened their research o... Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or misdiagnosed.In recent years,as researchers from all over the world have further deepened their research on FLPT,there has been a breakthrough in the classification,and the methods and principles of clinical management have changed accordingly;however,there is still no standardized guideline for the diagnosis and management of FLPT,and there have been few relevant literature review articles related to this kind of fracture in the past at least 5 years.In this article,we review the clinical classification,classification-based therapeutic recommendations,and prognosis of FLPT,with the aim of providing a reference for the clinical diagnosis and management of this infrequent fracture. 展开更多
关键词 fracture of the lateral process of the talus fracture of the talus Hindfoot injuries Intraarticular fracture Subtalar joint
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A modified 3D mean strain energy density criterion for predicting shale mixed-mode Ⅰ/Ⅲ fracture toughness
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作者 Kun Zheng Chaolin Wang +2 位作者 Yu Zhao Jing Bi Haifeng Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2411-2428,共18页
The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic fracturing.The edge-notched disk bending(ENDB)specimens are ... The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic fracturing.The edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi shale.To theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture criteria.By distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is proposed.As the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is observed.Our results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar manner.The macroscopic fracture signatures are consistent with those of triaxial hydraulic fracturing.The average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than true.Compared to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods. 展开更多
关键词 Longmaxi shale Hydraulic fracturing fracture mechanisms fracture criteria Mixed-modeⅠ/Ⅲfracture toughness Edge-notched disk bending
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Factors Influencing Proppant Transportation and Hydraulic Fracture Conductivity in Deep Coal Methane Reservoirs
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作者 Fan Yang Honggang Mi 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2637-2656,共20页
The gas production of deep coalbed methane wells in Linxing-Shenfu block decreases rapidly,the water output is high,the supporting effect is poor,the effective supporting fracture size is limited,and the migration mec... The gas production of deep coalbed methane wells in Linxing-Shenfu block decreases rapidly,the water output is high,the supporting effect is poor,the effective supporting fracture size is limited,and the migration mechanism of proppant in deep coal reservoir is not clear at present.To investigate the migration behavior of proppants in complex fractures during the volume reconstruction of deep coal and rock reservoirs,an optimization test on the conductivity of low-density proppants and simulations of proppant migration in complex fractures of deep coal reservoirs were conducted.The study systematically analyzed the impact of various fracture geometries,proppant types and fracturingfluid viscosities on proppant distribution.Furthermore,the study compared the outcomes of dynamic proppant transport experiments with simulation results.The results show that the numerical simulation is consistent with the results of the proppant dynamic sand-carrying experiment.Under the conditions of low viscosity and large pumping-rate,a high ratio of 40/70 mesh proppant can facilitate the movement of the proppant to the depths of fractures at all levels.The technical goal is to create comprehensive fracture support within intricate trapezoidal fractures in deep coal and rock reservoirs without inducing sand plugging.The sand ratio is controlled at 15%–20%,with a proppant combination ratio of 40/70:30/50:20/40=6:3:1.Proppant pumping operations can effectively address the issue of poor support in complex fractures in deep coal formations.The research results have been successfully applied to the development of deep coalbed methane in the Linxing-Shenfu block,Ordos Basin. 展开更多
关键词 Deep coal fracture reticular fracture proppant density fracture conductivity proppant transportation
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Borehole stability in naturally fractured rocks with drilling mud intrusion and associated fracture strength weakening:A coupled DFN-DEM approach
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作者 Yaoran Wei Yongcun Feng +4 位作者 Zhenlai Tan Tianyu Yang Xiaorong Li Zhiyue Dai Jingen Deng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1565-1581,共17页
Borehole instability in naturally fractured rocks poses significant challenges to drilling.Drilling mud invades the surrounding formations through natural fractures under the difference between the wellbore pressure(P... Borehole instability in naturally fractured rocks poses significant challenges to drilling.Drilling mud invades the surrounding formations through natural fractures under the difference between the wellbore pressure(P w)and pore pressure(P p)during drilling,which may cause wellbore instability.However,the weakening of fracture strength due to mud intrusion is not considered in most existing borehole stability analyses,which may yield significant errors and misleading predictions.In addition,only limited factors were analyzed,and the fracture distribution was oversimplified.In this paper,the impacts of mud intrusion and associated fracture strength weakening on borehole stability in fractured rocks under both isotropic and anisotropic stress states are investigated using a coupled DEM(distinct element method)and DFN(discrete fracture network)method.It provides estimates of the effect of fracture strength weakening,wellbore pressure,in situ stresses,and sealing efficiency on borehole stability.The results show that mud intrusion and weakening of fracture strength can damage the borehole.This is demonstrated by the large displacement around the borehole,shear displacement on natural fractures,and the generation of fracture at shear limit.Mud intrusion reduces the shear strength of the fracture surface and leads to shear failure,which explains that the increase in mud weight may worsen borehole stability during overbalanced drilling in fractured formations.A higher in situ stress anisotropy exerts a significant influence on the mechanism of shear failure distribution around the wellbore.Moreover,the effect of sealing natural fractures on maintaining borehole stability is verified in this study,and the increase in sealing efficiency reduces the radial invasion distance of drilling mud.This study provides a directly quantitative prediction method of borehole instability in naturally fractured formations,which can consider the discrete fracture network,mud intrusion,and associated weakening of fracture strength.The information provided by the numerical approach(e.g.displacement around the borehole,shear displacement on fracture,and fracture at shear limit)is helpful for managing wellbore stability and designing wellbore-strengthening operations. 展开更多
关键词 Borehole stability Naturally fractured rocks Weakening of fracture strength Discrete fracture network Distinct element method
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Management of geriatric acetabular fractures:Contemporary treatment strategies
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作者 Theodoros Tosounidis Byron Chalidis 《World Journal of Clinical Cases》 SCIE 2024年第13期2151-2156,共6页
Acetabular fractures in the geriatric population are typically low-energy fractures resulting from a fall from standing height.Compromised bone quality in the elderly,as well as this population’s concomitant medical ... Acetabular fractures in the geriatric population are typically low-energy fractures resulting from a fall from standing height.Compromised bone quality in the elderly,as well as this population’s concomitant medical comorbidities,render the management of such fractures challenging and controversial.Non-operative management remains the mainstay of treatment,although such a choice is associated with numerous and serious complications related to both the hip joint as well as the general condition of the patient.On the other hand,operatively treating acetabular fractures(e.g.,with osteosynthesis or total hip arthroplasty)is gaining popularity.Osteosynthesis can be performed with open reduction and internal fixation or with minimally invasive techniques.Total hip arthroplasty could be performed either in the acute phase combined with osteosynthesis or as a delayed procedure after a period of non-operative management or after failed osteosynthesis of the acetabulum.Regardless of the implemented treatment,orthogeriatric co-management is considered extremely crucial,and it is currently one of the pillars of a successful outcome after an acetabular fracture. 展开更多
关键词 Acetabular fractures Geriatric fractures fracture fixation Total hip arthroplasty MORTALITY MORBIDITY
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Beyond the imaging evaluation of fractures of the lateral process of the talus:Let’s not forget concomitant injuries
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作者 Cristian Lindner Pedro Reyes +1 位作者 Eduardo Molina Andrés Olave 《World Journal of Clinical Cases》 SCIE 2024年第30期6410-6412,共3页
Fractures of the lateral process of the talus(FLPT)are uncommon fractures that represent a clinical challenge.Traditional radiological classification systems rely predominantly on radiographic findings.However,due to ... Fractures of the lateral process of the talus(FLPT)are uncommon fractures that represent a clinical challenge.Traditional radiological classification systems rely predominantly on radiographic findings.However,due to the high rate of FLPT misdiagnosis and the limited accuracy in evaluating concomitant talar injuries through plain radiographs,novel imaging classification systems have been developed that aim to enhance the diagnosis of concomitant talar injuries,thereby optimizing patient management and reducing the incidence of long-term complications. 展开更多
关键词 TALUS Bone fracture Subtalar joint Hindfoot injuries fracture of the talus Intraarticular fracture
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Epidemiologic investigation of pediatric distal humerus fractures: An American insurance claims database study
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作者 Kyle Jay Klahs Jake E Dertinger +4 位作者 Grant T Mello Kevin Thapa Alexis B Sandler E'Stephan J Jesus Garcia Nata Parnes 《World Journal of Orthopedics》 2024年第1期52-60,共9页
BACKGROUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(ME)fractu... BACKGROUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(ME)fractures.AIM To evaluate the epidemiology of pediatric distal humerus fractures(SC,LC,and ME)from an American insurance claims database.METHODS A retrospective review was performed on patients 17 years and younger with the ICD 9 and 10 codes for SC,LC and ME fractures based on the IBM Truven MarketScan®Commercial and IBM Truven MarketScan Medicare Supplemental databases.Patients from 2015 to 2020 were queried for treatments,patient age,sex,length of hospitalization,and comorbidities.RESULTS A total of 1133 SC,154 LC,and 124 ME fractures were identified.SC fractures had the highest percentage of operation at 83%,followed by LC(78%)and ME fractures(41%).Male patients were,on average,older than female patients for both SC and ME fractures.CONCLUSION In the insurance claims databases used,SC fractures were the most reported,followed by LC fractures,and finally ME fractures.Age was identified to be a factor for how a pediatric distal humerus fractures,with patients with SC and LC fractures being younger than those with ME fractures.The peak age per injury per sex was similar to reported historic central tendencies,despite reported trends for younger physiologic development. 展开更多
关键词 Supracondylar humerus fracture Lateral condyle fracture Medial epicondyle fracture Pediatric elbow Truven Epidemiology
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Treatment of a femoral neck fracture combined with ipsilateral femoral head and intertrochanteric fractures: A case report
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作者 Xiang Yu Yu-Zhi Li +1 位作者 Hai-Jian Lu Bing-Li Liu 《World Journal of Orthopedics》 2024年第10期973-980,共8页
BACKGROUND This article presents a rare case of a complex hip fracture involving the ipsilateral femoral neck,trochanter,and femoral head,that was accompanied by hip dislocation.Currently,there is no established stand... BACKGROUND This article presents a rare case of a complex hip fracture involving the ipsilateral femoral neck,trochanter,and femoral head,that was accompanied by hip dislocation.Currently,there is no established standard treatment method for this specific type of fracture.Therefore,it is crucial to comprehensively consider factors such as patient age,fracture type,and degree of displacement to achieve a successful outcome.CASE SUMMARY A 38-year-old man sustained a comminuted fracture of his right hip as a result of a car accident.The injuries included a fracture of the femoral head,a fracture of the femoral neck,an intertrochanteric fracture of the femur,and a posterior dislocation of the hip on the same side.We opted for a treatment approach combining the use of a proximal femoral locking plate,cannulated screws,and Kirschner wires.Following the surgery,we developed an individualized rehabil-itation program to restore patient limb function.CONCLUSION For this complex fracture,we selected appropriate internal fixation and for-mulated individualized rehabilitation,which ultimately achieved good results. 展开更多
关键词 Locking plate Femoral neck fracture Femoral head fracture Intertrochanteric fracture Open reduction and internal fixation Case report
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