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Effect of fracture fluid flowback on shale microfractures using CT scanning 被引量:2
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作者 Jiale He Zhihong Zhao +6 位作者 Yiran Geng Yuping Chen Jianchun Guo Cong Lu Shouyi Wang Xueliang Han Jun Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期426-436,共11页
The field data of shale fracturing demonstrate that the flowback performance of fracturing fluid is different from that of conventional reservoirs,where the flowback rate of shale fracturing fluid is lower than that o... The field data of shale fracturing demonstrate that the flowback performance of fracturing fluid is different from that of conventional reservoirs,where the flowback rate of shale fracturing fluid is lower than that of conventional reservoirs.At the early stage of flowback,there is no single-phase flow of the liquid phase in shale,but rather a gas-water two-phase flow,such that the single-phase flow model for tight oil and gas reservoirs is not applicable.In this study,pores and microfractures are extracted based on the experimental results of computed tomography(CT)scanning,and a spatial model of microfractures is established.Then,the influence of rough microfracture surfaces on the flow is corrected using the modified cubic law,which was modified by introducing the average deviation of the microfracture height as a roughness factor to consider the influence of microfracture surface roughness.The flow in the fracture network is simulated using the modified cubic law and the lattice Boltzmann method(LBM).The results obtained demonstrate that most of the fracturing fluid is retained in the shale microfractures,which explains the low fracturing fluid flowback rate in shale hydraulic fracturing. 展开更多
关键词 SHALE Flowback of fracturing fluid MICROfracturE Lattice Boltzmann method(LBM)
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Complication rates after direct anterior vs posterior approach for hip hemiarthroplasty in elderly individuals with femoral neck fractures 被引量:2
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作者 Tatiana Charles Nicolas Bloemers +1 位作者 Bilal Kapanci Marc Jayankura 《World Journal of Orthopedics》 2024年第1期22-29,共8页
BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with ... BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with no consensus regarding the superiority of any single approach.AIM To compare early postoperative complications after implementing the direct anterior and posterior approaches(PL)for hip hemiarthroplasty after femoral neck fractures.METHODS This is a comparative,retrospective,single-center cohort study conducted at a university hospital.Between March 2008 and December 2018,273 patients(a total of 280 hips)underwent bipolar hemiarthroplasties(n=280)for displaced femoral neck fractures using either the PL(n=171)or the minimally invasive direct anterior approach(DAA)(n=109).The choice of approach was related to the surgeons’practices;the implant types were similar and unrelated to the approach.Dislocation rates and other complications were reviewed after a minimum followup of 6 mo.RESULTS Both treatment groups had similarly aged patients(mean age:82 years),sex ratios,patient body mass indexes,and patient comorbidities.Surgical data(surgery delay time,operative time,and blood loss volume)did not differ significantly between the groups.The 30 d mortality rate was higher in the PL group(9.9%)than in the DAA group(3.7%),but the difference was not statistically significant(P=0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the PL group(14/154;9.1%)than in the DAA group(0/105;0%)(P=0.002).Of the 14 patients with dislocation,8 underwent revision surgery for recurrent instability(posterior group),and one of them had 2 additional procedures due to a deep infection.The rate of other complications(e.g.,perioperative and early postoperative periprosthetic fractures and infection-related complications)did not differ significantly between the groups.CONCLUSION These findings suggest that the DAA to bipolar hemiarthroplasty for patients with femoral neck fractures is associated with a lower dislocation rate(<1%)than the PL. 展开更多
关键词 HEMIARTHROPLASTY Femoral neck fracture Direct anterior approach Posterior approach DISLOCATION MORTALITY
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Evaluating the stability and volumetric flowback rate of proppant packs in hydraulic fractures using the lattice Boltzmann-discrete element coupling method 被引量:1
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作者 Duo Wang Sanbai Li +2 位作者 Rui Wang Binhui Li Zhejun Pan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2052-2063,共12页
The stability and mobility of proppant packs in hydraulic fractures during hydrocarbon production are numerically investigated by the lattice Boltzmann-discrete element coupling method(LB-DEM).This study starts with a... The stability and mobility of proppant packs in hydraulic fractures during hydrocarbon production are numerically investigated by the lattice Boltzmann-discrete element coupling method(LB-DEM).This study starts with a preliminary proppant settling test,from which a solid volume fraction of 0.575 is calibrated for the proppant pack in the fracture.In the established workflow to investigate proppant flowback,a displacement is applied to the fracture surfaces to compact the generated proppant pack as well as further mimicking proppant embedment under closure stress.When a pressure gradient is applied to drive the fluid-particle flow,a critical aperture-to-diameter ratio of 4 is observed,above which the proppant pack would collapse.The results also show that the volumetric proppant flowback rate increases quadratically with the fracture aperture,while a linear variation between the particle flux and the pressure gradient is exhibited for a fixed fracture aperture.The research outcome contributes towards an improved understanding of proppant flowback in hydraulic fractures,which also supports an optimised proppant size selection for hydraulic fracturing operations. 展开更多
关键词 Numerical simulation Hydraulic fracturing Proppant flowback Closure stress Particulate flow
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Visualization and characterization of experimental hydraulic fractures interacting with karst fracture-cavity distributions
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作者 Hanzhi Yang Xin Chang +4 位作者 Chunhe Yang Wuhao Guo Lei Wang Guokai Zhao Yintong Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1667-1683,共17页
Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and explo... Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and exploitation.Proppant fracturing is considered as the best method for exploiting carbonate reservoirs;however,previous studies primarily focused on the effects of individual types of geological formations,such as natural fractures or cavities,on fracture propagation.In this study,true-triaxial physical simulation experiments were systematically performed under four types of stress difference conditions after the accurate prefabrication of four types of different fracture-cavity distributions in artificial samples.Subsequently,the interaction mechanism between the hydraulic fractures and fracture-cavity structures was systematically analyzed in combination with the stress distribution,cross-sectional morphology of the main propagation path,and three-dimensional visualization of the overall fracture network.It was found that the propagation of hydraulic fractures near the cavity was inhibited by the stress concentration surrounding the cavity.In contrast,a natural fracture with a smaller approach angle(0°and 30°)around the cavity can alleviate the stress concentration and significantly facilitate the connection with the cavity.In addition,the hydraulic fracture crossed the natural fracture at the 45°approach angle and bypassed the cavity under higher stress difference conditions.A new stimulation effectiveness evaluation index was established based on the stimulated reservoir area(SRA),tortuosity of the hydraulic fractures(T),and connectivity index(CI)of the cavities.These findings provide new insights into the fracturing design of carbonate reservoirs. 展开更多
关键词 Karst fracture-cavity reservoir fracturing experiment fracture propagation Cross-sectional morphology Stimulation effectiveness
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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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Characteristics of proppant transport and placement within rough hydraulic fractures
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作者 HUANG Hai ZHENG Yong +5 位作者 WANG Yi WANG Haizhu NI Jun WANG Bin YANG Bing ZHANG Wentong 《Petroleum Exploration and Development》 SCIE 2024年第2期453-463,共11页
A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to per... A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to perform proppant transport experiments.The typical characteristics of proppant transport and placement in rough fractures and its intrinsic mechanisms are investigated,and the influences of fracture inclination,fracture width and fracturing fluid viscosity on proppant transport and placement in rough fractures are analyzed.The results show that the rough fractures cause variations in the shape of the flow channel and the fluid flow pattern,resulting in the bridging buildup during proppant transport to form unfilled zone,the emergence of multiple complex flow patterns such as channeling,reverse flow and bypassing of sand-carrying fluid,and the influence on the stability of the sand dune.The proppant has a higher placement rate in inclined rough fractures,with a maximum increase of 22.16 percentage points in the experiments compared to vertical fractures,but exhibits poor stability of the sand dune.Reduced fracture width aggravates the bridging of proppant and induces higher pumping pressure.Increasing the viscosity of the fracturing fluid can weaken the proppant bridging phenomenon caused by the rough fractures. 展开更多
关键词 reservoir fracturing rough fracture PROPPANT transport and placement characteristics bridging buildup
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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints
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作者 Guiyun Gao Chenghu Wang Ke Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1637-1648,共12页
The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determinati... The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable results.In this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests required.Different shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo method.Thereafter,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress constraints.The inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress tensor.Two stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)method.The results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress gradient.The inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints employed.The M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole. 展开更多
关键词 Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing
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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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Influences of shale microstructure on mechanical properties and bedding fractures distribution
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作者 Ming-Zhe Gu Mao Sheng +2 位作者 Shi-Zhong Cheng Fan-Hao Gong Gen-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1944-1954,共11页
The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution patterns.In this paper,the microstructure and mechanical properties of Longmaxi marine shale an... The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution patterns.In this paper,the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD),field emission scanning electron microscope(FE-SEM)with mineral analysis system,and nanoindentation.Additionally,the typical bedding layers area was properly stratified using Focused Ion Beam(FIB),and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were analyzed.The results show that the Longmaxi marine shale sample contains more clay mineral grains,while the Qingshankou continental shale sample contains more hard brittle mineral grains such as feldspar.For Longmaxi marine shale sample,hard brittle minerals with grain sizes larger than 20μm is18.24%and those with grain sizes smaller than 20μm is 16.22%.For Qingshankou continental shale sample,hard brittle minerals with grain sizes larger than 20μm is 40.7%and those with grain sizes smaller than 20μm is 11.82%.In comparison to the Qingshankou continental shale sample,the Longmaxi marine shale sample has a lower modulus,hardness,and heterogeneity.Laminated shales are formed by alternating coarse-grained and fine-grained layers during deposition.The average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale sample.The two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained deposition.The orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle grains.The fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou continental shale.The current research provides guidelines for the effective development of shale reservoirs in various sedimentary environments. 展开更多
关键词 SHALE NANOINDENTATION MICROSTRUCTURE Mechanical property fracture
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Clinical outcomes of triceps reflecting anconeus pedicle and olecranon osteotomy approach for distal humerus intercondylar fractures
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作者 Rohit Ailani Sanjeev Kumar Bhuyan +2 位作者 Brejesh Kumar Prasad Amit Kumar Namrata Dawani 《World Journal of Orthopedics》 2024年第6期570-577,共8页
BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation.While there is consensus about the posterior approach,several posterior approaches have been develo... BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation.While there is consensus about the posterior approach,several posterior approaches have been developed.It is debatable as to which approach is best.AIM To compare triceps reflecting anconeus pedicle(TRAP)and olecranon osteotomy approaches for internal fixation of distal humeral intercondylar fracture.METHODS In total,40 cases of Arbeitsgemeinschaft für Osteosynthesefragen/Association of the Study of Internal Fixation type C,closed,and Gustilo type I intercondylar humeral fractures were included.Patients ranged in age from 18 years to 70 years.The patients were randomized into two groups:TRAP group and olecranon osteotomy group,with 20 cases in each.All were followed up at 6 wk,3 months,6 months,and 12 months.Functional outcomes were measured in terms of flexion-extension arc,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score.RESULTS The mean age was 43.2 years in the TRAP group and 37.5 years in the olecranon osteotomy group.The mean operative time and mean duration of hospital stay in the TRAP group were significantly higher than in the olecranon osteotomy group(119.5 vs 111.5 min and 9.85 vs 5.45 d,respectively).The mean arc of flexion-extension,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score were comparable without any significant difference in the groups at the 12-month follow-up(107.0 vs 106.2,18.3 vs 15.7,and 84.2 vs 86.2,respectively).Ulnar paresthesia and superficial infections were comparable in both groups(2 cases vs 3 cases and 3 cases vs 2 cases,respectively).Hardware prominence was significantly higher in the olecranon osteotomy group,mostly due to tension band wiring.CONCLUSION Both approaches were equivalent,but there is a need for further study including higher numbers of subjects and longer study duration to prove the benefits of one approach over the other. 展开更多
关键词 Elbow joint Humeral fracture OSTEOTOMY INTERNAL fracture fixation
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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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Clinical Study of Tianji Robotic-Assisted Surgery for Upper Cervical Spine Fractures
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作者 Chengkua Huang Yuanjian Huang +6 位作者 Weikang Yang Qianhou Zhou Xianhai Zeng Junlei Tan Mei Zhang Guosheng Su Sheng Nong 《Natural Science》 2024年第9期150-161,共12页
Object: To compare the safety, clinical efficacy, and complication rate of “Tianji” robot-assisted surgery with traditional open surgery in the treatment of cervical vertebrae fracture. Methods: 60 patients with upp... Object: To compare the safety, clinical efficacy, and complication rate of “Tianji” robot-assisted surgery with traditional open surgery in the treatment of cervical vertebrae fracture. Methods: 60 patients with upper cervical vertebrae fracture admitted to Baise People’s Hospital between November 2018 and April 2024 were retrospectively analyzed. Among these patients, 29 underwent “Tianji” robot-assisted surgery (Robot group), and 31 underwent traditional C-arm fluoroscopy-assisted open surgery (Open group). Statistical analysis of the data was performed using SPSS 27.0 software to compare general data (gender, age, BMI), preoperative and postoperative visual analogue scale (VAS) scores, neck disability index (NDI), intraoperative blood loss, accuracy of screw placement on imaging, and the number of complications in both groups for comprehensive evaluation. A P value < 0.05 was deemed to have achieved statistical significance. Results: There was no significant difference in preoperative VAS scores between the two groups (Robot group: 8.34 ± 0.61;Open group: 8.26 ± 0.68, P = 0.317). There was also no significant difference in VAS scores at 1 week postoperatively (Robot group: 6.90 ± 0.31;Open group: 6.94 ± 0.36, P = 0.3237). Preoperative NDI scores showed no significant difference between the two groups (Robot group: 43.31 ± 2.67;Open group: 43.84 ± 2.67, P = 0.2227), and the difference in NDI scores at 1 week postoperatively was also not significant (Robot group: 35.69 ± 4.24;Open group: 37.35 ± 3.48, P = 0.0509). Intraoperative blood loss in the Robot group was significantly lower than in the Open group (246.21 ± 209 ml vs 380.65 ± 328.04 ml, P = 0.0308), with a statistically significant difference. The operation time was longer in the Robot group (3.75 ± 0.74 h) compared to the Open group (2.74 ± 0.86 h). In terms of screw placement accuracy, the Robot group had a higher accuracy rate for Class A screws compared to the Open group (102 screws vs 94 screws, P = 0.0487), and the accuracy rate for Class B screws was also higher in the Robot group (13 screws vs 29 screws, P = 0.0333), with both differences being statistically significant. There was no significant difference in the number of complications between the two groups (Robot group: 8 cases;Open group: 10 cases, P = 0.6931). Conclusion: Patients treated with “Tianji” robot-assisted surgery for upper cervical vertebrae fracture had lower intraoperative blood loss and higher screw placement accuracy compared to those undergoing traditional C-arm fluoroscopy-assisted open surgery, indicating that this robot-assisted surgery can effectively reduce intraoperative blood loss and improve screw placement accuracy. 展开更多
关键词 Tiangui Robot Assisted Surgery Upper Cervical Spine fracture Clinical Study fracture Repair
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Rare Bilateral Radius and Ulna Fractures: A Case Report
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作者 Kwabena Nana Achiaw Dankwa Ekins Kuuzie Samuel Kwame Ofori 《Open Journal of Orthopedics》 2024年第1期1-11,共11页
Introduction: Forearm fractures involving both the radius and ulna, present distinctive challenges in orthopedic trauma management. This case report explores the complexities of a rare case of bilateral fractures, emp... Introduction: Forearm fractures involving both the radius and ulna, present distinctive challenges in orthopedic trauma management. This case report explores the complexities of a rare case of bilateral fractures, emphasizing the importance of a comprehensive approach for optimal outcomes. Case Presentation: This report presents the case of a 40-year-old motorcyclist who was involved in a road accident and arrived at the emergency department shortly after the incident. Clinical examination revealed closed fractures in both forearms with mild swelling and severe tenderness. Fortunately, no neurovascular issues or compartment syndrome were detected. The patient was administered intravenous fluids and effective pain relief. Forearm splints were applied and the arms were elevated using pillows. Radiographs showed fractures in the right distal radius and ulna, as well as the left mid-shaft radius and ulna. Under general anesthesia, open reduction and internal fixation were per-formed using plates and screws for all four fractures. Postoperatively, the patient’s arms were immobilized and elevated, with gradual recovery during follow-up appointments over six months, eventually achieving full function without complaints. Conclusion: This article highlights the possibility, although infrequent, of bilateral shaft fractures of the ulna and radius. With thorough clinical assessment and radiological investigation, such fractures can be well-defined. The required definitive treatment, which usually involves open reduction and internal fixation, can be performed. 展开更多
关键词 FOREARM fracturE ULNAR RADIUS BILATERAL
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A Comparative Study of Mandibular Fractures in Senegal: Children vs. Adults
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作者 Paul Niang 《Open Journal of Stomatology》 2024年第2期72-76,共5页
Introduction: The commonest maxillofacial fractures involve the mandible. Age can be considered among influential factors. Aim of the Study: To compare mandibular fractures between children and adults from the beginni... Introduction: The commonest maxillofacial fractures involve the mandible. Age can be considered among influential factors. Aim of the Study: To compare mandibular fractures between children and adults from the beginning up to the treatment in Senegal. Patients and Method: A three-year retrospective study was conducted in a university hospital. The medical records of patients admitted for maxillofacial injuries were reviewed. Patient and injury-related variables including age, gender, etiology, average consultation delay, anatomic location of fracture and treatment were compared up to age of 15 and beyond that. Results: Considering 272 casualties, maxillofacial fractures were less frequent among children than adults (36.7% and 59.7%) and were mainly mandibular (90.1% and 91.4%). Male predilection (sex ratio of 2.4 and 4.9) was twice (2) as pronounced from the age of 16. The average consultation delay was two (2) times shorter for children. Road traffic accidents which predominated among children (33.9%) had comparable frequency (32.3%) although they were outnumbered by assault (37.6%) among adults. Fractures occurred mainly on the corpus (90.1% and 90.4%), particularly on parasymphysis (40.1%) up to the age of 15, whereas angle fractures increased (8.5% to 19.6%) and joint damage decreased afterwards. Intra-oral orthopedic procedures (91.2% and 92.6%) in which mandibular retention splints were more common (37.3%) up to the age of 15 then arch ligatures (49%) were then widely favored. Conclusion: Differences relating to the distribution of causes but also to the anatomic location on the corpus and to the choice of intra-oral orthopedic procedures within overall similarities between children and adults regarding the male predilection, the frequency of road traffic accidents, the mandibular injuries, but also the school therapeutic attitude consisting of favoring the orthopedic option. 展开更多
关键词 fracturE MANDIBLE CHILD ADULT
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Management of Mandibular Fractures in Children in Ivory Coast: Experience of the Stomatology and Maxillofacial Surgery Department at the University Hospital of Cocody from 2000 to 2019
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作者 Bakary Ouattara Camille Assouan +8 位作者 Laurent Boka Koffi Konan René Kouakou Ake Lucien Jonathan Yapo Annick Zoglo-Bro Ahi Morel Mounin Chapo Affoué Linda Marie Pierre Koffi Kahder Morel Diarra Atse Kobo N’Guessan Konan Marc Koffi 《Open Journal of Stomatology》 2024年第7期341-349,共9页
Introduction: Mandibular fractures in children are becoming increasingly common. Treatment of these fractures is difficult due to their anatomical and physiological complexity. Therefore, there is a need for well-codi... Introduction: Mandibular fractures in children are becoming increasingly common. Treatment of these fractures is difficult due to their anatomical and physiological complexity. Therefore, there is a need for well-codified management. Our main aim was to develop a decision algorithm for the management of mandibular fractures in children based on our experience. Materials and Methods: This was a retrospective descriptive study carried out in the Department of Stomatology and Maxillofacial Surgery at the University Hospital of Cocody over a period of 20 years (2000-2019). Results: We enrolled 58 patients. The mean age of the patients was 9.35 ± 2.3 years with a sex ratio of 2.22. Traffic accidents were the main cause of mandibular fractures (60.35%). Condylar fractures were the most common (46.87%). Treatment was orthopedic in 45.76% of cases, mixed (orthopedic and surgical) in 24.14% and surgical in 5.17%. Patients were followed up weekly for 1 month, then monthly for 6 months and annually for 3 years, with panoramic radiographs of the maxilla starting at 21 days. We observed 2 cases of complications: temporomandibular ankylosis and gingival stomatitis. Conclusion: Mandibular fractures are common in children. Management is difficult due to anatomical and physiological peculiarities. The choice of treatment depends on several criteria. 展开更多
关键词 fractures MANDIBLE CHILDREN Treatment Ivory Coast
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 fractures Development characteristics Controlling factors Shale oil Sweet spot
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Effect of navigation endoscopy combined with threedimensional printing technology in the treatment of orbital blowout fractures
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作者 Jin-Hai Yu Yao-Hua Wang +3 位作者 Qi-Hua Xu Chao Xiong An-An Wang Hong-Fei Liao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期570-576,共7页
●AIM:To explore the combined application of surgical navigation nasal endoscopy(NNE)and three-dimensional printing technology(3DPT)for the adjunctive treatment of orbital blowout fractures(OBF).●METHODS:Retrospectiv... ●AIM:To explore the combined application of surgical navigation nasal endoscopy(NNE)and three-dimensional printing technology(3DPT)for the adjunctive treatment of orbital blowout fractures(OBF).●METHODS:Retrospective analysis was conducted on the data of patients with OBF who underwent surgical treatment at the Affiliated Eye Hospital of Nanchang University between July 2012 and November 2022.The control group consisted of patients who received traditional surgical treatment(n=43),while the new surgical group(n=52)consisted of patients who received NNE with 3DPT.The difference in therapeutic effects between the two groups was evaluated by comparing the duration of the operation,best corrected visual acuity(BCVA),enophthalmos difference,recovery rate of eye movement disorder,recovery rate of diplopia,and incidence of postoperative complications.●RESULTS:The study included 95 cases(95 eyes),with 63 men and 32 women.The patients’age ranged from 5 to 67y(35.21±15.75y).The new surgical group and the control group exhibited no statistically significant differences in the duration of the operation,BCVA and enophthalmos difference.The recovery rates of diplopia in the new surgical group were significantly higher than those in the control group at 1mo[OR=0.03,95%CI(0.01–0.15),P<0.0000]and 3mo[OR=0.11,95%CI(0.03–0.36),P<0.0000]postoperation.Additionally,the recovery rates of eye movement disorders at 1 and 3mo after surgery were OR=0.08,95%CI(0.03–0.24),P<0.0000;and OR=0.01,95%CI(0.00–0.18),P<0.0000.The incidence of postoperative complications was lower in the new surgical group compared to the control group[OR=4.86,95%CI(0.95–24.78),P<0.05].●CONCLUSION:The combination of NNE and 3DPT can shorten the recovery time of diplopia and eye movement disorder in patients with OBF. 展开更多
关键词 orbital blowout fracture three-dimensional printing ENDOSCOPY surgical navigation
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Results of Open Surgical Treatment of Humeral Paddle Fractures about 63 Cases
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作者 Mansi Zied Chermiti Wajdi +4 位作者 Rbai Hedi Saadana Jacem Zaidi Bacem Sindi Sihem Gazzah Wael 《Open Journal of Orthopedics》 2024年第1期83-91,共9页
Fractures of the humeral paddle, common to young adults, are most often complex, linked to violence and an increase in road accidents. The objective of our work is to evaluate our functional results, in the medium ter... Fractures of the humeral paddle, common to young adults, are most often complex, linked to violence and an increase in road accidents. The objective of our work is to evaluate our functional results, in the medium term, correlated with a review of the literature. This is a retrospective study of 63 patients, carried out in the traumatology-orthopedics department 1 of the IBN EL JAZZAR hospital in KAIROUAN, over a period of 7 years from January 2015 to December 2021. The average age of patients was 39 years (17 - 68 years). Predominantly male. The etiologies are dominated by falls and accidents on public roads. Fractures are classified according to the Müller and Allgöwer classification where type C is found in 51% of cases. All our patients undergo an olecranon osteotomy in 71% of cases. Osteosynthesis using a Lecestre plate combined with screwing or plugging is used in 84% of cases. The evolution is marked by complications observed in eight patients (16%), including two cases of sepsis, four cases of elbow stiffness (8%), one case of joint callus and one case of pseudarthrosis. Our results are evaluated according to the Mayo Elbow Performance Score, they are excellent and good in 71% of cases, average in 18% of cases and poor in 11% of cases. Fractures of the humeral paddle are fractures with a satisfactory functional prognosis, requiring ad integrum anatomical restoration and solid osteosynthesis allowing early rehabilitation of the elbow. One case of joint callus and one case of pseudarthrosis. 展开更多
关键词 fracturE Humeral Paddle Surgical Treatment
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Extraction of fractures in shale CT images using improved U-Net
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作者 Xiang Wu Fei Wang +3 位作者 Xiaoqiu Zhang Bohua Han Qianru Liu Yonghao Zhang 《Energy Geoscience》 EI 2024年第2期240-248,共9页
Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscal... Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscale to the rock matrix,and traditional algorithms have difficulty to achieve accurate segmentation results.In this study,a dataset containing multiscale fracture information was constructed,and a U-Net semantic segmentation model with a scSE attention mechanism was used to classify shale CT images at the pixel level and compare the results with traditional methods.The results showed that the CLAHE algorithm effectively removed noise and enhanced the fracture information in the dark parts,which is beneficial for further fracture extraction.The Canny edge detection algorithm had significant false positives and failed to recognize the internal information of the fractures.The Otsu algorithm only extracted fractures with a significant difference from the background and was not sensitive enough for fine fractures.The MEF algorithm enhanced the edge information of the fractures and was also sensitive to fine fractures,but it overestimated the aperture of the fractures.The U-Net was able to identify almost all fractures with good continuity,with an MIou and Recall of 0.80 and 0.82,respectively.As the image resolution increases,more fine fracture information can be extracted. 展开更多
关键词 CT slices fracture segmentation SHALE U-Net Deep learning
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