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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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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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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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Characteristics of proppant transport and placement within rough hydraulic fractures 被引量:1
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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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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:3
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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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Three-dimensional(3D) Printing Technology Assisted by Minimally Invasive Surgery for Pubic Rami Fractures 被引量:8
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作者 Wen-bo NIE Fa-gang YE +4 位作者 Jian-lin MA Jiang-ping YU Ming-xing WANG Zhen-hua ZHANG Fu-jie SUN 《Current Medical Science》 SCIE CAS 2018年第5期827-833,共7页
The feasibility of three-dimensional (3D) printing technology cgmbined with minimally invasive surgery in the treatment of pubic rami fractures was explored.From August 2015 to October 2017,a series of 30 patients who... The feasibility of three-dimensional (3D) printing technology cgmbined with minimally invasive surgery in the treatment of pubic rami fractures was explored.From August 2015 to October 2017,a series of 30 patients who underwent surgical stabilization of their anterior pelvic ring (all utilizing the 3D printing technology)by one surgeon at a single hospital were studied.The minimally invasive incisions were made through anterior inferior cilia spine and pubic nodule.Data collected included the operative duration,the blood loss,the damage of the important tissue,the biographic union and therecovery of the function after the operation.Measurements on inlet and outlet pelvic cardiograph were made immediately post-operation and at all follow-up clinic visits.The scores of reduction and function were measured during follow-up.Results showed that the wounds of 30 patients were healed in the first stage,and there was no injury of important structures such as blood vessels and nerves.According to the Matta criteria,excellent effectiveness was obtained in 22 cases and good in 8 cases.According to the functional evaluation criteria of Majeed,excellent effectiveness was obtained in 21 cases and good in 9 cases.It was suggested that the 3D printing technology assisted by minimally invasive surgery can better evaluate the pelvic fracture before operation,which was helpful in plate modeling, and can shorten surgery duration and reduce intraoperative blood loss and complications. The positioning accuracy was improved,and better surgical result was finally achieved. 展开更多
关键词 digital design THREE-DIMENSIONAL printing ANTERIOR ring PELVIC fractures MINIMALLY INVASIVE surgery
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Comparative efficacy of proximal femoral nail vs dynamic condylar screw in treating unstable intertrochanteric fractures 被引量:1
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +2 位作者 Mohanad Abdulgadir Ayman E Abbas Duha Lutfi Turjuman 《World Journal of Orthopedics》 2024年第8期796-806,共11页
BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment ... BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment efficacy of dynamic condylar screws(DCS)and proximal femoral nails(PFN)for unstable intertrochanteric fractures.METHODS To find pertinent randomized controlled trials and retrospective observational studies comparing PFN with DCS for the management of unstable femoral intertrochanteric fractures,a thorough search was carried out.For research studies published between January 1996 and April 2024,PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar were all searched.The complete texts of the papers were retrieved,vetted,and independently examined by two investigators.Disputes were settled by consensus,and any disagreements that persisted were arbitrated by a third author.RESULTS This study included six articles,comprising a total of 173 patients.Compared to the DCS,the PFN had a shorter operation time[mean difference(MD):-41.7 min,95%confidence interval(95%CI):-63.04 to-20.35,P=0.0001],higher success rates with closed reduction techniques[risk ratio(RR):34.05,95%CI:11.12-104.31,P<0.00001],and required less intraoperative blood transfusion(MD:-1.4 units,95%CI:-1.80 to-1.00,P<0.00001).Additionally,the PFN showed shorter fracture union time(MD:-6.92 wk,95%CI:-10.27 to-3.57,P<0.0001)and a lower incidence of reoperation(RR:0.37,95%CI:0.17-0.82,P=0.01).However,there was no discernible variation regarding hospital stay,implant-related complications,and infections.CONCLUSION Compared to DCS,PFN offers shorter operative times,reduces the blood transfusions requirements,achieves higher closed reduction success,enables faster fracture healing,and lowers reoperation incidence. 展开更多
关键词 Intertrochanteric fracture UNSTABLE Dynamic condylar screw Proximal femoral nail META-ANALYSIS Comparative study
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Full-endoscopic spine surgery treatment of lumbar foraminal stenosis after osteoporotic vertebral compression fractures:A case report 被引量:2
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作者 Quan-Lai Zhao Kun-Peng Hou +2 位作者 Zhong-Xuan Wu Liang Xiao Hong-Guang Xu 《World Journal of Clinical Cases》 SCIE 2022年第2期656-662,共7页
BACKGROUND Few reports have described lumbar foraminal stenosis-induced radiculopathy after treatment by full-endoscopic spine surgery(FESS)combined with percutaneous vertebroplasty(PVP)in patients with vertebral comp... BACKGROUND Few reports have described lumbar foraminal stenosis-induced radiculopathy after treatment by full-endoscopic spine surgery(FESS)combined with percutaneous vertebroplasty(PVP)in patients with vertebral compression fractures.We herein report such a case,including the patient’s treatment process and doctor’s surgical experience.CASE SUMMARY A 79-year-old man presented with symptoms of radiculopathy after sustaining L4 vertebral compression fractures.Imaging and physical examination revealed L4 vertebral compression fractures combined with L3/4 Lumbar foraminal stenosis(LFS).The patient’s symptoms were low back pain with pain in the lateral left leg.Although many reports have described radiculopathy induced by osteoporotic vertebral compression fractures,the use of FESS combined with PVP has rarely been reported.This case report indicates that the combination of FESS and PVP is a safe and effective approach for the treatment of LFS-induced radiculopathy after vertebral compression fractures.This minimally invasive technique has great potential to replace traditional lumbar fixation and decompression surgery.Thus,we suggest the continued accumulation of similar cases to discuss the wider application of FESS.CONCLUSION For patients with osteoporotic vertebral compression fracture(OVCF)and LFS,PVP and FESS can be used to restore the vertebral height and reduce the pressure around the intervertebral foramen.Additionally,the combination of FESS and PVP can treat the pain or numbness of the low back and lower limbs and allow for recovery in a short time with excellent postoperative effects.In general,FESS is a good treatment for radiculopathy caused by foraminal stenosis after OVCF. 展开更多
关键词 Osteoporotic vertebral compression fracture Lumbar foraminal stenosis Percutaneous vertebroplasty Full-endoscopic spine surgery RADICULOPATHY Case report
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Multiple damage zones around hydraulic fractures generated by high-frequency pulsating hydraulic fracturing
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作者 Yan Peng Sheng-Jie Wei +2 位作者 Guang-Qing Zhang Da-Wei Zhou Chuang-Chao Xu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2688-2702,共15页
Pulsating hydraulic fracturing(PHF)is a promising fracturing method and can generate a dynamic periodic pressure.The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture.I... Pulsating hydraulic fracturing(PHF)is a promising fracturing method and can generate a dynamic periodic pressure.The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture.If the frequency of periodic pressure exceeds 10 Hz,the distribution of pressure along the main fracture will be heterogeneous,which is much different from the one induced by the common fracturing method.In this study,the impact of this special spatial feature of pressure on hydraulic fracture is mainly investigated.A coupled numerical simulation model is first proposed and verified through experimental and theoretical solutions.The mechanism of secondary fracture initiation around the main fracture is then discovered.In addition,sensitivity studies are conducted to find out the application potential of this new method.The results show that(1)this coupled numerical simulation model is accurate.Through comparison with experimental and theoretical data,the average error of this coupled model is less than 1.01%.(2)Even if a reservoir has no natural fracture,this heterogeneous distribution pressure can also cause many secondary fractures around the main fracture.(3)The mechanism of secondary fracture initiation is that this heterogeneous distribution pressure causes tensile stress at many locations along the main fracture.(4)Through adjusting the stimulation parameters,the stimulation efficiency can be improved.The average and amplitude of pressure can increase possibility of secondary fracture initiation.The frequency of this periodic pressure can increase number of secondary fractures.Even 6 secondary fractures along a 100 m-length main fracture can be generated.(5)The influence magnitudes of stimulation parameters are larger than ones of geomechanical properties,therefore,this new fracturing method has a wide application potential. 展开更多
关键词 Tight reservoir Reservoir stimulation Numerical simulation Secondary fracture fracture initiation
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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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A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures
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作者 Jun Li Ming-Yi Wu +2 位作者 Xu Han Si-Yuan He Ze-Yu Lin 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2583-2599,共17页
Low-permeability reservoirs are generally characterized by low porosity and low permeability.Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir reco... Low-permeability reservoirs are generally characterized by low porosity and low permeability.Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor.In recent years,hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing fluid.However,the transportation of the proppant is inefficient in the low-viscosity fluid,and the proppant has a low piling-up height in fracture channels.These key challenges restrict the fluid(natural gas or oil)flow in fracture channels and their functional flow areas,reducing the profits of hydrocarbon exploitation.This study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber.Its structure was similar to that of dandelion seeds,and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional proppant.Moreover,the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model,rough fracture model,narrow fracture model,complex fracture model,large-scale single fracture model,and small-scale single fracture model).Experimental results indicated that,compared with the traditional proppant,the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid.Compared with the traditional proppant,the dandelionbased bionic proppant had 0.1-4 times longer transportation length,0.3-5 times higher piling-up height,and 2-10 times larger placement area.The newly developed proppant also had some other extraordinary features.The tortuosity of the fracture did not influence the transportation of the novel proppant.This proppant could easily enter the branch fracture and narrow fracture with a high packing area in rough surface fractures.Based on the aforementioned characteristics,this novel proppant technique could improve the proppant transportation efficiency in the low-viscosity fracturing fluid and increase the ability of the proppant to enter the secondary fracture.This study might provide a new solution for effectively exploiting low-permeability hydrocarbon reservoirs. 展开更多
关键词 Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation
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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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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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Effectiveness and postoperative rehabilitation of one-stage combined anterior-posterior surgery for severe thoracolumbar fractures with spinal cord injury 被引量:1
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作者 Bo Zhang Jin-Chao Wang +2 位作者 Yu-Zhen Jiang Qing-Peng Song Yan An 《World Journal of Clinical Cases》 SCIE 2022年第18期6001-6008,共8页
BACKGROUND Thoracolumbar fractures are generally combined with spinal cord injury to varying degrees,which may cause deterioration of the patients’condition and increase the difficulty of clinical treatment.At presen... BACKGROUND Thoracolumbar fractures are generally combined with spinal cord injury to varying degrees,which may cause deterioration of the patients’condition and increase the difficulty of clinical treatment.At present,anterior or combined anterior-posterior surgery is preferred for severe thoracolumbar fractures.AIM To investigate the effectiveness and postoperative rehabilitation of one-stage combined anterior-posterior surgery for severe thoracolumbar fractures with spinal cord injury.METHODS One-hundred-and-twenty patients who received surgery for severe thoracolumbar fractures with spinal cord injury at our hospital from February 2018 to February 2020 were randomly enrolled.They were randomly divided into group 1(one-stage combined anterior-posterior surgery,n=60)and group 2(onestage anterior-approach surgery,n=60).Treatment efficacy was compared between the two groups.RESULTS Blood loss was greater and the operation time was longer in group 1 than in group 2,and the differences were statistically significant(P<0.05).Incision length,intraoperative X-rays,and length of hospital stay were not significantly different between the two groups(P>0.05).Preoperative function of the affected vertebrae was not significantly different between the two groups(P>0.05).In each group,the patients showed significant improvement after surgery.The anterior vertebral height ratio and the posterior vertebral height ratio in group 1 after surgery were significantly higher than those in group 2.The Cobb angle after surgery was significantly lower in group 1 than in group 2(P<0.05).The canal-occupying ratio of the affected vertebrae was not significantly different between the two groups(P>0.05).Before surgery,there was no significant difference in the quality of life scores between the two groups(P>0.05).The above indicators were significantly improved after surgery compared with before surgery in each group.In addition,these indicators were markedly better in group 1 than in group 2 after surgery(P<0.05 for each).CONCLUSION One-stage combined anterior-posterior surgery effectively improves the function of the affected vertebrae and the life quality of patients with severe thoracolumbar fractures and spinal cord injury.This surgical approach is worthy of popularization in clinical use. 展开更多
关键词 Thoracolumbar fracture Spinal cord injury Combined anterior-posterior surgery Postoperative rehabilitation Quality of life
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Systematic prediction of the gas content, fractures, and brittleness in fractured shale reservoirs with TTI medium
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作者 Yun Zhao Xiao-Tao Wen +2 位作者 Chen-Long Li Yang Liu Chun-Lan Xie 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3202-3221,共20页
The main objective is to optimize the development of shale gas-rich areas by predicting seismic sweet spot parameters in shale reservoirs. We systematically assessed the fracture development, fracture gas content, and... The main objective is to optimize the development of shale gas-rich areas by predicting seismic sweet spot parameters in shale reservoirs. We systematically assessed the fracture development, fracture gas content, and rock brittleness in fractured gas-bearing shale reservoirs. To better characterize gas-bearing shale reservoirs with tilted fractures, we optimized the petrophysical modeling based on the equivalent medium theory. Based on the advantages of shale petrophysical modeling, we not only considered the brittle mineral fraction but also the combined effect of shale porosity, gas saturation, and total organic carbon(TOC) when optimizing the brittleness index. Due to fractures generally functioning as essential channels for fluid storage and movement, fracture density and fracture fluid identification factors are critical geophysical parameters for fractured reservoir prediction. We defined a new fracture gas indication factor(GFI) to detect fracture-effective gas content. A new linear PP-wave reflection coefficient equation for a tilted transversely isotropic(TTI) medium was rederived, realizing the direct prediction of anisotropic fracture parameters and the isotropic elasticity parameters from offset vector tile(OVT)-domain seismic data. Synthetic seismic data experiments demonstrated that the inversion algorithm based on the L_P quasinorm sparsity constraint and the split-component inversion strategy exhibits high stability and noise resistance. Finally, we applied our new prediction method to evaluate fractured gas-bearing shale reservoirs in the Sichuan Basin of China, demonstrating its effectiveness. 展开更多
关键词 Petrophysical modeling Brittleness index fracture gas indication factor(GFI) Tilted transversely isotropic(TTI) fracture density
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