BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges f...BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges from nonoperative methods to surgical interventions such as intramedullary K-wires,which promote faster rehabilitation and improved elbow mobility.AIM To evaluate the outcomes of managing humeral shaft fractures using closed reduction and internal fixation with flexible intramedullary K-wires.METHODS This was a retrospective cohort study analyzing the medical records of patients with humeral shaft fractures managed with flexible intramedullary K-wires at King Abdulaziz Medical City,using non-random sampling and descriptive analysis for outcome evaluation.RESULTS This study assessed the clinical outcomes of 20 patients treated for humeral shaft fractures with intramedullary K-wires.Patients were predominantly male(n=16,80%),had an average age of 39.2 years,and a mean body mass index of 29.5 kg/m^(2).The fractures most frequently occurred in the middle third of the humerus(n=14,70%),with oblique fractures being the most common type(n=7,35%).All surgeries used general anesthesia and a posterior approach,with no intraoperative complications reported.Postoperatively,all patients achieved clinical and radiological union(n=20,100%),and the majority(n=13,65%)reached an elbow range of motion from 0 to 150 degrees.CONCLUSION These results suggest that intramedullary K-wire fixation may be an effective option for treating humeral shaft fractures,with favorable outcomes in range of motion recovery,fracture union,and a low rate of intraoperative complications.展开更多
Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current ev...Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes.展开更多
Objective Supracondylar humerus fractures are the most frequent fractures of the paediatric elbow.The present study introduced a modified surgical procedure for treatment of supracondylar humerus fractures in children...Objective Supracondylar humerus fractures are the most frequent fractures of the paediatric elbow.The present study introduced a modified surgical procedure for treatment of supracondylar humerus fractures in children.Methods From February 2015 to August 2019,73 patients with Gartland’s type II and III supracondylar fractures were treated with this modified method.Totally,68 of all patients were followed up for 3–12 months(mean 8.25 months).The evaluation results included fracture nonunion,ulnar nerve injury,pin track infection,carrying angle and elbow joint Flynn score.Results The results showed that bone union was observed in all children,one case had an iatrogenic ulnar nerve injury,and the symptoms were completely relieved in 4 months after removing of the medial-side pin.All children had no cubitus varus deformity and no pin track infection,and the rate of satisfactory results according to Flynn’s criteria score was 100%.Conclusion The modified closed reduction and Kirschner wires internal fixation could effectively reduce the rate of open reduction,the risk of iatrogenic ulnar nerve injury,and the incidence of cubitus varus deformity in treatment of supracondylar humerus fractures in children.展开更多
Complex segmental femoral fractures are usually not amenable to closed reduction. The purpose of this study was to evaluate a series of patients who had undergone four pins assisted reduc- tion and intramedullary nail...Complex segmental femoral fractures are usually not amenable to closed reduction. The purpose of this study was to evaluate a series of patients who had undergone four pins assisted reduc- tion and intramedullary nail fixation to determine the therapeutic effect of this closed reduction tech- nique. Between December 2010 and January 2013, 15 consecutive patients with segmental femoral fractures were treated with four pins assisted reduction at our hospital. The patient was placed in a supine position on a radiolucent fracture table and a. gentle traction was attempted on the limb. Usu- ally, the proximal fracture segment exhibited the typical deformity of flexion, external rotation, and abduction, the middle segment exhibited adduction and distal fracture segment exhibited flexion. Four Schanz pins were placed percutaneously to fix one cortex and did not penetrate into the me- dullary cavity, and the ＂T＂ sharp handles were fixed on the Schanz pins. The fragments were then re- duced by reversing the deforming forces for segmental fractures by two assistants~ And then, the re- duction could be easily achieved and intramedullary nail fixation was performed. Radiographs were evaluated for the quality of the reduction and fracture union. Closed reduction was achieved in all pa- tients using the four pins technology. All 15 fractures united uneventfully. No patient had a rotational malunion or limb length discrepancy at the time of the last follow-up. Thirteen of the fifteen （86.7%） patients had anatomic reduction and two of them （13.3%） had minor varus alignment of 3° and 5°. Knee stiffness was Observed in 2 patients and no implant failure was observed. Surgical treatment of complex segmental femoral fractures With four pins assisted reduction and intramedullary nail fixation techniques can result in excellent reductions and a high union rate.展开更多
Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point o...Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point of the medial femoral condyle. Femoral shaft fractures often result from high energy forces. These fractures occur mostly among young adults. Objective: This was to determine the epidemiological pattern of closed femoral shaft fractures in a regional tertiary hospital in Enugu, Nigeria. Method: The study was a prospective study over a 12 month period (June 2015-May 2016) at National Orthopaedic Hospital, Enugu. Following ethical approval and written informed consent, patients were consecutively recruited. The patients were clinically and radiographically evaluated at presentation. The diagnosis of closed femoral shaft fractures were made from the physical examination finding of absent open wound communicating with the fracture hematoma in the thigh and anteroposterior (AP) and lateral x-rays of the affected thigh confirming the fracture pattern. The data collected included patients’ demographics, the cause of injury, the side of injury and anatomic site of the injury among other parameters. The data were collected using well designed and structured proforma. Results: A total of 52 femoral shaft fractures in 50 patients were included and analyzed using SPSS version 20.0. The age range of the patients is 18 - 85 years with a median age of 39.1 ± 14.9 years. The most commonly affected age group is 21 - 30 years. There was male preponderance with a male to female ratio of 2.3:1. Majority of the fractures (76.9%) resulted from road traffic crashes most commonly following motor vehicular accident (36.5%). Majority of the fractures (92.3%) are unilateral with right side to left side ratio of 1.2:1. Majority of the patients (51.9%) had Winquist Hansen grade III type of fracture. The most common associated injury is fractures of tibia/fibula followed by fracture of the neck of the ipsilateral femur. All the patients were treated operatively using either locked intramedullary nailing technique or plating technique. Majority of the patients (59.6%) were discharged between 10th and 29th day post-operatively. Conclusion: From the results of this study, it is concluded that most of the closed femoral shaft fractures were caused by high energy trauma from road traffic crashes. It is therefore recommended that proper education of motorists on good use of roads and strict adherence to traffic rules will significantly help in preventing the occurrence of these fractures in our environment.展开更多
To observe the effects of closed reduction and percutaneous K wires fixation of displacd supracondylar humerus fracture in children MethodsRetrospective review of fourteen patients who s...To observe the effects of closed reduction and percutaneous K wires fixation of displacd supracondylar humerus fracture in children MethodsRetrospective review of fourteen patients who sustained displaced supracondylar fracture of distal humerus treated by closed reduction and percutaneous K wires fixation Results. All patients’ K wires were removed at 4 weeks post operation Their elbow function regained at 8 weeks The average period of followed up was 10 month (varies from 6 to 18 month), all fractures healed very well without any permanent complications Two transient nerves palsy,ulnar and radial nerve each, recovered completely at 12 weeks and 16 weeks post operation respectively Conclusion. Closed reduction and percutaneous K wires fixation is a safe and efficient treatment for displaced humerus surpracondylar fracture in children展开更多
Introduction: Recently, intramedullary nailing for displaced middle third fractures of clavicle has received wide attention. Though open nailing has been widely described, closed nailing finds less mention. This paper...Introduction: Recently, intramedullary nailing for displaced middle third fractures of clavicle has received wide attention. Though open nailing has been widely described, closed nailing finds less mention. This paper therefore aims to study the outcome of closed titanium elastic nailing for displaced mid-clavicular fractures. Material and Methods: This was a prospective study of 34 patients with displaced middle third clavicle fracture who underwent closed intramedullary nailing with titanium elastic nail at a tertiary care centre. The operative time, length of incision, time for radiological union, pain and functional outcome after union were noted. Results: The mean operative time was 34.33 mins. The mean time of discharge was 2.25 days. The average time of radiological union was 10.23 weeks. All the patients achieved full, painless range of motion of the ipsilateral shoulder. The average Constant-Murley score at 12 months was 94.28 indicating excellent result. Conclusion: Closed titanium elastic nailing offers a safe and minimally invasive method of fixation for fractures of middle-third clavicle with excellent functional outcome.展开更多
Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The ...Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The databases of CNKI,Wanfang,Weipu,Chinese biomedical literature,Pubmed,Embase,and Cochrane Library were retrieved,and the randomized controlled studies that directly compared the efficacy of plate internal fixation and closed reduction external fixation in the treatment of distal radius fractures published publicly from the establishment of the database to April 2023 were collected.The two researchers independently screened the retrieved literature according to the inclusion and exclusion criteria,extracted data,used Cochrane risk bias assessment tool for quality assessment,and used RevMan 5.4 software for meta analysis.Results:A total of 10 randomized controlled trials were included,all of which were in English.There were 1042 patients in total,and 9 of them were rated as low risk.Meta analysis results showed that one year after the treatment of distal radius fracture with volar locking plate internal fixation,DASH score[MD=-5.64,95%CI(-7.21,-4.06),P<0.00001];One year later,PRWE score[MD=-5.90,95%CI(-8.88,-2.92),P=0.001];Palm flexion[MD=5.92,95%CI(1.29,10.55),P=0.01];Pronation[MD=2.48,95%CI(0.59,4.36),P=0.01];Postrotation[MD=4.73,95%CI(2.15,7.31),P=0.0003];Grip strength[MD=0.61,95%CI(0.12,1.10),P=0.02];palmar tilt angle[MD=9.84,95%CI(5.66,14.02),P<0.00001];Radial inclination[MD=4.33,95%CI(2.97,5.69),P<0.00001]was superior to closed reduction plaster or splint external fixation.One year later,the European Five dimensional Health Scale(EQ-5D-5L)score[MD=0.02,95%CI(-0.01,0.05),P=0.27];Back extension[MD=2.22,95%CI(-4.15,8.59),P=0.49];Ulnar deviation[MD=3.49,95%CI(-0.80,7.78),P=0.11];Radial deviation[MD=2.05,95%CI(-2.39,6.50),P=0.37];Ulnar variance[MD=-1.14,95%CI(-3.16,0.88),P=0.27];There was no significant difference in complications[MD=0.77,95%CI(0.54,1.10),P=0.16](P>0.05).Conclusion:Based on the current clinical data,internal fixation with volar locking plate is more conducive to mid-term DASH score and grip strength recovery than closed reduction plaster or splint external fixation,but there is no significant difference in the quality of life and complications of patients.For adult distal radius fractures,surgical indications should be carefully grasped,and non operative treatment should be given priority.展开更多
BACKGROUND Radial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures.An antegrade nailing surgical technique is becoming popular for the fixation o...BACKGROUND Radial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures.An antegrade nailing surgical technique is becoming popular for the fixation of these fractures with minimal invasiveness.We analyzed nerve recovery in patients with humeral shaft fracture and radial nerve palsy treated with humeral nail fixation without nerve exploration.AIM To assess the radial nerve recovery rate and time from humeral shaft fracture with surgical treatment using close nailing.METHODS We retrospectively collected data of patients who underwent undergone surgical nail fixation for humeral shaft fractures between October 1,2016,and March 31,2020.Subsequently,we analyzed the primary or secondary radial nerve palsy recovery rate and radial nerve motor function recovery time.RESULTS The study included 70 patients who underwent surgical treatment for closed-or Gustilo type I open humeral shaft fractures using a nail fixation technique without radial nerve exploration.The patients suffered from primary(n=5)and secondary(n=5)radial nerve palsy.A 100%radial nerve recovery rate was achieved.The mean recovery time was 4.3 mo.CONCLUSION The study results indicate full recovery of radial nerve palsies from humeral shaft fracture using close nailing treatment.Surgeons need not be concerned about the occurrence of permanent nerve palsies.展开更多
BACKGROUND Traumatic hip dislocation usually occurs following high-velocity trauma.It is imperative that the dislocation be reduced in a timely manner,especially in a closed manner,as an orthopedic emergency.However,c...BACKGROUND Traumatic hip dislocation usually occurs following high-velocity trauma.It is imperative that the dislocation be reduced in a timely manner,especially in a closed manner,as an orthopedic emergency.However,closed reduction can hardly be achieved in patients who also have ipsilateral lower extremity fractures.Herein,we focus on hip dislocation associated with ipsilateral lower extremity fractures,excluding intracapsular fractures(femoral head and neck fractures),present an early closed hip joint reduction method for this injury pattern,and review the literature to discuss the appropriate closed reduction technique for this rare injury pattern.CASE SUMMARY We report a case of a 37-year-old male who sustained a left acetabular posterior wall fracture,an ipsilateral comminuted subtrochanteric fracture and dislocation of the hip.The hip dislocation was reduced urgently in a closed manner using the joy-stick technique with a T-shaped Schanz screw.The fractures were reduced and fixed as a 2nd-stage surgery procedure.At the 17-month postoperative follow-up,the patient had full range of motion of the affected hip.CONCLUSION Closed reduction of a hip dislocation associated with ipsilateral lower extremity fractures is rarely achieved by regular maneuvers.Attempts at closed reduction,by means of indirectly controlling the proximal fracture fragment or reconstructing the femoral leverage rapidly with the aid of various external reduction apparatuses,were shown to be effective in some scenarios.Mandatory open reduction is indicated in cases of failed closed reduction,particularly in irreducible dislocations.展开更多
Self-suspended proppants,which enable clear-water fracturing,represent a promising new class of materials for reservoir stimulation.Given the economic limitations associated with their exclusive use,this study investi...Self-suspended proppants,which enable clear-water fracturing,represent a promising new class of materials for reservoir stimulation.Given the economic limitations associated with their exclusive use,this study investigates proppant transport behavior in hybrid systems combining self-suspended proppants with conventional 40/70 mesh quartz sand at various mixing ratios.A dedicated experimental apparatus was developed to replicate field-relevant complex fracture networks,consisting of a main fracture and two branching fractures with different deflection angles.Using this system,sand bank formation and proppant distribution were examined for both conventional quartz sand fracturing and fracturing augmented with self-suspended proppants.The effects of slurry discharge volume,proppant mixing ratio,sand ratio,and injection location of the self-suspended proppant on transport and placement behavior were systematically analyzed.According to the results,the incorporation of self-suspended proppants markedly enhances the proppant-carrying capacity of the slurry and substantially modifies sand bank morphology.Increasing the discharge volume raises the inlet slope angle and promotes greater proppant penetration into branch fractures.The proportion of self-suspended proppant governs slurry viscoelasticity and,consequently,proppant settling behavior.As the fraction of self-suspended proppant decreases,the equilibrium height of the sand bank increases,while the proppant mass fraction within branch fractures exhibits a non-monotonic response,initially decreasing and then increasing.Variations in sand ratio alter both overall proppant concentration and the self-suspended proppant-to-water ratio,thereby modulating slurry rheology and influencing proppant placement.In addition,changes in injection location affect near-wellbore vortex structures,leading to distinct sand bank morphologies.展开更多
In permafrost regions of the QinghaiXizang Plateau,embankments of the Qinghai-Xizang Highway and Qinghai-Xizang Railway experiencing roadside water accumulation exhibit more pronounced engineering deteriorations.A wid...In permafrost regions of the QinghaiXizang Plateau,embankments of the Qinghai-Xizang Highway and Qinghai-Xizang Railway experiencing roadside water accumulation exhibit more pronounced engineering deteriorations.A widely accepted view is that the accumulated water adjacent to the embankment possesses substantial thermal energy,which accelerates the degradation-even disappearance-of the underlying permafrost.Moreover,the presence of roadside water keeps the embankment soil in a persistently high-moisture state,thereby making the frozen-soil embankment more susceptible to deformation under traffic loading.However,in the permafrost regions of the QinghaiXizang Plateau,deteriorations of embankments affected by roadside water are more commonly manifested as undulating pavement surfaces,and extensive crack networks appear on the embankment crest even where thermosyphons are installed.These manifestations are not fully consistent with the deterioration mechanisms proposed by existing viewpoints.We propose the hypothesis that temperature gradients,formed due to the freezing and thawing processes between the roadside wateraffected soil and the roadbed soil,lead to moisture migration under the influence of temperature gradients,resulting in frost heave and thaw settlement in the roadbed soil.To validate this hypothesis,we conducted the following investigations sequentially.Initially,we selected a roadbed with a thermosyphon(TPCT)system,which has a significant cooling effect,as the study object.By analyzing the temperature monitoring data of the roadbed section,the temperature variance was calculated to identify the time nodes where the temperature gradient of the roadbed soil was maximum and minimum.Subsequently,corresponding roadbed temperature distribution maps were drawn,illustrating the changes in the temperature and position of the lowtemperature core near the TPCT over time.Furthermore,using small-scale indoor model experiments,we qualitatively concluded that moisture in the soil migrates toward the TPCT due to the temperature gradient.Thereafter,combining borehole water content data and precipitation data from the sloped terrain construction site,the formation mechanisms and timing characteristics of roadside water accumulation were analyzed.Ultimately,by integrating the ground temperature data,air temperature data,roadside water formation mechanisms,and the operating characteristics of the TPCT,it was concluded that roadside water,while in a thawed state during TPCT operation,acts as a supplementary source for moisture migration in the roadbed soil.This migration leads to cracking in the TPCT roadbed.Therefore,this study reveals a novel damage mechanism:asynchronous freeze-thaw processes induce temperature gradients,which drive the migration of roadside water into the roadbed and are responsible for the cracking damage.展开更多
The research presented in this paper aimed to analyze the evolution of fractures in strata in relation to the progress of longwall mining.To achieve this objective,an introscopic probe equipped with a highresolution c...The research presented in this paper aimed to analyze the evolution of fractures in strata in relation to the progress of longwall mining.To achieve this objective,an introscopic probe equipped with a highresolution camera was developed,along with additional equipment that enables continuous recording of the internal surfaces of drainage boreholes exceeding 100 m in depth.The probe was utilized to test two methane drainage boreholes in the Z-3b longwall,which operates within the 501/3 coal seam of the Jankowice mine in Poland.Automatic image analysis methods were applied to evaluate the recorded images,based on a newly developed classificationsystem for fractures categorized by size and number.The results were compared with an analysis of changes in the methane capture rate from the drainage boreholes,which correlated with longwall mining progress.A strong correlation was observed between the number of fractures and the lithology of the strata layers.The largest number of fractures and their evolution were recorded in the coal layers,followed by the shale layers,while the sandstone layers exhibited the least number of fractures.Based on parallel measurements of the methane capture rate from the drainage boreholes during the progress of longwall mining,the extent of the strata's fracture zone was determined to range from 6 m to 36 m.Within the fracture zone,the strata are highly fractured,which leads to an increase in methane emissions through seepage and diffusion processes.展开更多
Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane(CBM)development,where the mechanical properties of gangue layers exert a significant control on fracture propagati...Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane(CBM)development,where the mechanical properties of gangue layers exert a significant control on fracture propagation behavior.To address the unclear mechanisms governing fracture penetration across coal-gangue interfaces,this study employs the Continuum-Discontinuum Element Method(CDEM)to simulate and analyze the vertical propagation of hydraulic fractures initiating within coal seams,based on geomechanical parameters derived from the deep Benxi Formation coal seams in the southeastern Ordos Basin.The investigation systematically examines the influence of geological and operational parameters on cross-interfacial fracture growth.Results demonstrate that vertical stress difference,elastic modulus contrast between coal and gangue layers,interfacial stress differential,and interfacial cohesion at coal-gangue interfaces are critical factors governing hydraulic fracture penetration through these interfaces.High vertical stress differences(>3 MPa)inhibit interfacial dilation,promoting predominant crosslayer fracture propagation.Reduced interfacial stress contrasts and enhanced interfacial cohesion facilitate fracture penetration across interfaces.Furthermore,smaller elastic modulus contrasts between coal and gangue correlate with increased interfacial aperture.Finally,lower injection rates effectively suppress vertical fracture propagation in deep coal reservoirs.This study elucidates the characteristics and mechanisms governing cross-layer fracture propagation in coal–rock composites with interbedded partings,and delineates the dynamic evolution laws and dominant controlling factors involved.Thefindings provide critical theoretical insights for the optimization of fracture design and the efficient development of deep coalbed methane reservoirs.展开更多
Background:Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure.Pedicle screws are primarily designed for internal fixation in spi...Background:Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure.Pedicle screws are primarily designed for internal fixation in spinal procedures.A key objec-tive of many orthopedic studies is to assess the biocompatibility of implants with bone and adjacent soft tissue.This study aims to evaluate the biocompatibility and effects of the Pedicle screw-Rod configuration as a novel external fixation method in canine tibial osteotomy.Methods:With ethics approval,eight healthy,intact male dogs,aged 10-12 months and weighing between 20 and 22 kg,underwent a minimally invasive medial tibial approach for surgical fixation of tibial osteotomy using a Pedicle screw-Rod configu-ration.Postoperative evaluations included ultrasound assessments at the osteotomy site and histological evaluations at the bone-screw interface.Results:B-mode ultrasound evaluation indicated healing progress at all osteotomy sites.The color Doppler examination revealed an initial increase in signals in the sur-rounding soft tissue during the first 4 weeks post-operation,followed by a decrease in signals within the adjacent soft tissue between the 5th and 8th weeks.During this latter period,the signals were primarily concentrated on the bone surface and the callus.The bone-screw interface at various screw sites exhibited similar histological changes,indicating effective integration of the newly formed woven bone into the screw threads.Conclusions:Fixation of non-articular tibial osteotomy with Pedicle screw-Rod con-figuration resulted in secondary bone healing,characterized by abundant callus for-mation and neovascularization.This implant demonstrated favorable biocompatibility with bone and surrounding soft tissue,without significant complications.展开更多
Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with ...Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with long bone fractures in the extremities admitted to Santai Hospital Affiliated to North Sichuan Medical College from January 2023 to January 2025 were included,including cases of upper extremity forearm fractures and lower extremity femoral and tibial fractures.The patients were evenly divided using a random number table,with the control group undergoing open reduction and internal fixation(ORIF)combined with autologous periosteum graft,and the observation group undergoing ORIF,autologous periosteum graft,and PRP injection.Surgical indicators,complication rates,excellent fracture healing rates,functional satisfaction,and joint range of motion were compared between the two groups.Results:The surgical indicators in the observation group were similar to those in the control group(p>0.05).The complication rate in the observation group was lower than that in the control group,while the excellent fracture healing rate and functional satisfaction were higher in the observation group(p<0.05).Conclusion:Autologous periosteum graft combined with PRP technology is safe and reliable for the treatment of long bone fractures in the extremities,with satisfactory clinical outcomes.展开更多
Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly a...Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly affecting the macromechanical properties and failure modes.These fractures affect the instability and failure of the surrounding rock,significantlyimpacting the overall stability of engineering structures.Herein,sand-powder three-dimensional(3D)printing technology was used to prepare rock-like specimens with internal fracture networks.Triaxial compression testing,post-failure fracture mapping,and fractal dimension analysis of the fracture surfaces were conducted to investigate the effects of dominant fracture angles on the strength and deformation of rocks with internal fracture networks under triaxial stress.The results indicate that the dominant fracture angle has a pronounced effect on the mechanical behavior of rock.With increasing angle,both compressive strength and elastic modulus exhibit an initial decline followed by an increase.Moreover,higher confiningpressure significantlyimproves the compressive strength of fractured rock.This enhancement weakens as the confiningpressure further increases.Moreover,with increasing confiningpressure,the differences between the maximum and minimum values of elastic moduli and lateral strain ratios in fractured rock gradually decrease.Thus,the impact of the dominant fracture angle on rock mass deformation decreases with increasing confiningpressure.This research elucidates the effects of dominant fracture angles on the mechanical and failure properties of complex fractured rock masses and the influenceof the confiningpressure on these relationships.It provides valuable theoretical insights and practical guidance for stability analyses in engineering rock masses.展开更多
One of the key challenges for underground rock reservoirs is ensuring prevention of the unwanted fluid leakage through rock fracture networks during their service life.Microbial-induced calcium carbonate precipitation...One of the key challenges for underground rock reservoirs is ensuring prevention of the unwanted fluid leakage through rock fracture networks during their service life.Microbial-induced calcium carbonate precipitation(MICP)technology has emerged as a promising bio-healing method for rock fractures with small apertures.In this study,a new“three-stage”injection strategy-based MICP(TS-MICP)bio-healing method was proposed,aiming to achieve a“three-high”performance that includes high bridging rate,high mechanical strength,and high homogeneity.A series of meter-scale rock fracture models were prepared to conduct TS-MICP grouting tests.Compared with the traditional injection strategy-based biohealing methods,the TS-MICP method significantly improved the bridging rate(32.1%e89.5%),mechanical properties(0.138e1.023 MPa),and homogeneity of CaCO_(3)precipitation(334.4%).Additionally,it achieved a higher material utilization rate(1.72 times higher),reducing the consumption of cementation solution(CS)by 258.8%,thereby demonstrating greater potential for field applications.The underlying mechanism for achieving high bridging rate and high homogeneity in CaCO_(3)precipitation can be attributed to the synergistic effects of the coupling injection strategy,which optimizes the advantages at each stage.In stage I,under the influence of gravity,the rapid flocculation and hydrogen bonding interactions of organic matter lead to formation of the dense and high-strength CaCO_(3)precipitation at the bottom using a low-concentration bacterial suspension(BS).This process establishes bridging steps along the wall sides for subsequent uniform CaCO_(3)precipitation.In stage II,concentrated BS is utilized to produce looser CaCO_(3)flocculation,which precipitates uniformly on the pre-existing bridging steps.In stage III,a two-step injection strategy was employed to reinforce the loose CaCO_(3)crystals formed in stages I and II,and finally forms a strong bridging effect with“three-high”performance.展开更多
A new algorithm based on an FC-tree （frequent closed pattern tree） and a max-FCIA （maximal frequent closed itemsets algorithm） is presented, which is used to mine the frequent closed itemsets for solving memory an...A new algorithm based on an FC-tree （frequent closed pattern tree） and a max-FCIA （maximal frequent closed itemsets algorithm） is presented, which is used to mine the frequent closed itemsets for solving memory and time consuming problems. This algorithm maps the transaction database by using a Hash table,gets the support of all frequent itemsets through operating the Hash table and forms a lexicographic subset tree including the frequent itemsets.Efficient pruning methods are used to get the FC-tree including all the minimum frequent closed itemsets through processing the lexicographic subset tree.Finally,frequent closed itemsets are generated from minimum frequent closed itemsets.The experimental results show that the mapping transaction database is introduced in the algorithm to reduce time consumption and to improve the efficiency of the program.Furthermore,the effective pruning strategy restrains the number of candidates,which saves space.The results show that the algorithm is effective.展开更多
BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appea...BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures.展开更多
基金approved by King Abdullah International Medical Research Center Ethics Committee(approval No.0000074524).
文摘BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges from nonoperative methods to surgical interventions such as intramedullary K-wires,which promote faster rehabilitation and improved elbow mobility.AIM To evaluate the outcomes of managing humeral shaft fractures using closed reduction and internal fixation with flexible intramedullary K-wires.METHODS This was a retrospective cohort study analyzing the medical records of patients with humeral shaft fractures managed with flexible intramedullary K-wires at King Abdulaziz Medical City,using non-random sampling and descriptive analysis for outcome evaluation.RESULTS This study assessed the clinical outcomes of 20 patients treated for humeral shaft fractures with intramedullary K-wires.Patients were predominantly male(n=16,80%),had an average age of 39.2 years,and a mean body mass index of 29.5 kg/m^(2).The fractures most frequently occurred in the middle third of the humerus(n=14,70%),with oblique fractures being the most common type(n=7,35%).All surgeries used general anesthesia and a posterior approach,with no intraoperative complications reported.Postoperatively,all patients achieved clinical and radiological union(n=20,100%),and the majority(n=13,65%)reached an elbow range of motion from 0 to 150 degrees.CONCLUSION These results suggest that intramedullary K-wire fixation may be an effective option for treating humeral shaft fractures,with favorable outcomes in range of motion recovery,fracture union,and a low rate of intraoperative complications.
文摘Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes.
基金supported by Program of the National Natural Science Foundation of China(No.82074233)Scientific Research Foundation for Advanced Talents,Xiang’an Hospital of Xiamen University(No.PM201809170009).
文摘Objective Supracondylar humerus fractures are the most frequent fractures of the paediatric elbow.The present study introduced a modified surgical procedure for treatment of supracondylar humerus fractures in children.Methods From February 2015 to August 2019,73 patients with Gartland’s type II and III supracondylar fractures were treated with this modified method.Totally,68 of all patients were followed up for 3–12 months(mean 8.25 months).The evaluation results included fracture nonunion,ulnar nerve injury,pin track infection,carrying angle and elbow joint Flynn score.Results The results showed that bone union was observed in all children,one case had an iatrogenic ulnar nerve injury,and the symptoms were completely relieved in 4 months after removing of the medial-side pin.All children had no cubitus varus deformity and no pin track infection,and the rate of satisfactory results according to Flynn’s criteria score was 100%.Conclusion The modified closed reduction and Kirschner wires internal fixation could effectively reduce the rate of open reduction,the risk of iatrogenic ulnar nerve injury,and the incidence of cubitus varus deformity in treatment of supracondylar humerus fractures in children.
基金supported by grants from the National Natural Science Foundation of China(No.81401789)the Key Medical Science Research Plan of Hebei Province(No.ZL2014208)
文摘Complex segmental femoral fractures are usually not amenable to closed reduction. The purpose of this study was to evaluate a series of patients who had undergone four pins assisted reduc- tion and intramedullary nail fixation to determine the therapeutic effect of this closed reduction tech- nique. Between December 2010 and January 2013, 15 consecutive patients with segmental femoral fractures were treated with four pins assisted reduction at our hospital. The patient was placed in a supine position on a radiolucent fracture table and a. gentle traction was attempted on the limb. Usu- ally, the proximal fracture segment exhibited the typical deformity of flexion, external rotation, and abduction, the middle segment exhibited adduction and distal fracture segment exhibited flexion. Four Schanz pins were placed percutaneously to fix one cortex and did not penetrate into the me- dullary cavity, and the ＂T＂ sharp handles were fixed on the Schanz pins. The fragments were then re- duced by reversing the deforming forces for segmental fractures by two assistants~ And then, the re- duction could be easily achieved and intramedullary nail fixation was performed. Radiographs were evaluated for the quality of the reduction and fracture union. Closed reduction was achieved in all pa- tients using the four pins technology. All 15 fractures united uneventfully. No patient had a rotational malunion or limb length discrepancy at the time of the last follow-up. Thirteen of the fifteen （86.7%） patients had anatomic reduction and two of them （13.3%） had minor varus alignment of 3° and 5°. Knee stiffness was Observed in 2 patients and no implant failure was observed. Surgical treatment of complex segmental femoral fractures With four pins assisted reduction and intramedullary nail fixation techniques can result in excellent reductions and a high union rate.
文摘Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point of the medial femoral condyle. Femoral shaft fractures often result from high energy forces. These fractures occur mostly among young adults. Objective: This was to determine the epidemiological pattern of closed femoral shaft fractures in a regional tertiary hospital in Enugu, Nigeria. Method: The study was a prospective study over a 12 month period (June 2015-May 2016) at National Orthopaedic Hospital, Enugu. Following ethical approval and written informed consent, patients were consecutively recruited. The patients were clinically and radiographically evaluated at presentation. The diagnosis of closed femoral shaft fractures were made from the physical examination finding of absent open wound communicating with the fracture hematoma in the thigh and anteroposterior (AP) and lateral x-rays of the affected thigh confirming the fracture pattern. The data collected included patients’ demographics, the cause of injury, the side of injury and anatomic site of the injury among other parameters. The data were collected using well designed and structured proforma. Results: A total of 52 femoral shaft fractures in 50 patients were included and analyzed using SPSS version 20.0. The age range of the patients is 18 - 85 years with a median age of 39.1 ± 14.9 years. The most commonly affected age group is 21 - 30 years. There was male preponderance with a male to female ratio of 2.3:1. Majority of the fractures (76.9%) resulted from road traffic crashes most commonly following motor vehicular accident (36.5%). Majority of the fractures (92.3%) are unilateral with right side to left side ratio of 1.2:1. Majority of the patients (51.9%) had Winquist Hansen grade III type of fracture. The most common associated injury is fractures of tibia/fibula followed by fracture of the neck of the ipsilateral femur. All the patients were treated operatively using either locked intramedullary nailing technique or plating technique. Majority of the patients (59.6%) were discharged between 10th and 29th day post-operatively. Conclusion: From the results of this study, it is concluded that most of the closed femoral shaft fractures were caused by high energy trauma from road traffic crashes. It is therefore recommended that proper education of motorists on good use of roads and strict adherence to traffic rules will significantly help in preventing the occurrence of these fractures in our environment.
文摘To observe the effects of closed reduction and percutaneous K wires fixation of displacd supracondylar humerus fracture in children MethodsRetrospective review of fourteen patients who sustained displaced supracondylar fracture of distal humerus treated by closed reduction and percutaneous K wires fixation Results. All patients’ K wires were removed at 4 weeks post operation Their elbow function regained at 8 weeks The average period of followed up was 10 month (varies from 6 to 18 month), all fractures healed very well without any permanent complications Two transient nerves palsy,ulnar and radial nerve each, recovered completely at 12 weeks and 16 weeks post operation respectively Conclusion. Closed reduction and percutaneous K wires fixation is a safe and efficient treatment for displaced humerus surpracondylar fracture in children
文摘Introduction: Recently, intramedullary nailing for displaced middle third fractures of clavicle has received wide attention. Though open nailing has been widely described, closed nailing finds less mention. This paper therefore aims to study the outcome of closed titanium elastic nailing for displaced mid-clavicular fractures. Material and Methods: This was a prospective study of 34 patients with displaced middle third clavicle fracture who underwent closed intramedullary nailing with titanium elastic nail at a tertiary care centre. The operative time, length of incision, time for radiological union, pain and functional outcome after union were noted. Results: The mean operative time was 34.33 mins. The mean time of discharge was 2.25 days. The average time of radiological union was 10.23 weeks. All the patients achieved full, painless range of motion of the ipsilateral shoulder. The average Constant-Murley score at 12 months was 94.28 indicating excellent result. Conclusion: Closed titanium elastic nailing offers a safe and minimally invasive method of fixation for fractures of middle-third clavicle with excellent functional outcome.
基金2022 Key Specialty Construction Project of Traditional Chinese Medicine:Traditional Chinese Orthopedics and Traumatology Department (No.962042)2020 Regional Traditional Chinese Medicine (Orthopedics and Traumatology)Diagnosis and Treatment Center (Jin Wei Zhong[2020]No.5)。
文摘Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The databases of CNKI,Wanfang,Weipu,Chinese biomedical literature,Pubmed,Embase,and Cochrane Library were retrieved,and the randomized controlled studies that directly compared the efficacy of plate internal fixation and closed reduction external fixation in the treatment of distal radius fractures published publicly from the establishment of the database to April 2023 were collected.The two researchers independently screened the retrieved literature according to the inclusion and exclusion criteria,extracted data,used Cochrane risk bias assessment tool for quality assessment,and used RevMan 5.4 software for meta analysis.Results:A total of 10 randomized controlled trials were included,all of which were in English.There were 1042 patients in total,and 9 of them were rated as low risk.Meta analysis results showed that one year after the treatment of distal radius fracture with volar locking plate internal fixation,DASH score[MD=-5.64,95%CI(-7.21,-4.06),P<0.00001];One year later,PRWE score[MD=-5.90,95%CI(-8.88,-2.92),P=0.001];Palm flexion[MD=5.92,95%CI(1.29,10.55),P=0.01];Pronation[MD=2.48,95%CI(0.59,4.36),P=0.01];Postrotation[MD=4.73,95%CI(2.15,7.31),P=0.0003];Grip strength[MD=0.61,95%CI(0.12,1.10),P=0.02];palmar tilt angle[MD=9.84,95%CI(5.66,14.02),P<0.00001];Radial inclination[MD=4.33,95%CI(2.97,5.69),P<0.00001]was superior to closed reduction plaster or splint external fixation.One year later,the European Five dimensional Health Scale(EQ-5D-5L)score[MD=0.02,95%CI(-0.01,0.05),P=0.27];Back extension[MD=2.22,95%CI(-4.15,8.59),P=0.49];Ulnar deviation[MD=3.49,95%CI(-0.80,7.78),P=0.11];Radial deviation[MD=2.05,95%CI(-2.39,6.50),P=0.37];Ulnar variance[MD=-1.14,95%CI(-3.16,0.88),P=0.27];There was no significant difference in complications[MD=0.77,95%CI(0.54,1.10),P=0.16](P>0.05).Conclusion:Based on the current clinical data,internal fixation with volar locking plate is more conducive to mid-term DASH score and grip strength recovery than closed reduction plaster or splint external fixation,but there is no significant difference in the quality of life and complications of patients.For adult distal radius fractures,surgical indications should be carefully grasped,and non operative treatment should be given priority.
文摘BACKGROUND Radial nerve palsy due to humeral shaft fracture is the most common peripheral nerve injury associated with long bone fractures.An antegrade nailing surgical technique is becoming popular for the fixation of these fractures with minimal invasiveness.We analyzed nerve recovery in patients with humeral shaft fracture and radial nerve palsy treated with humeral nail fixation without nerve exploration.AIM To assess the radial nerve recovery rate and time from humeral shaft fracture with surgical treatment using close nailing.METHODS We retrospectively collected data of patients who underwent undergone surgical nail fixation for humeral shaft fractures between October 1,2016,and March 31,2020.Subsequently,we analyzed the primary or secondary radial nerve palsy recovery rate and radial nerve motor function recovery time.RESULTS The study included 70 patients who underwent surgical treatment for closed-or Gustilo type I open humeral shaft fractures using a nail fixation technique without radial nerve exploration.The patients suffered from primary(n=5)and secondary(n=5)radial nerve palsy.A 100%radial nerve recovery rate was achieved.The mean recovery time was 4.3 mo.CONCLUSION The study results indicate full recovery of radial nerve palsies from humeral shaft fracture using close nailing treatment.Surgeons need not be concerned about the occurrence of permanent nerve palsies.
文摘BACKGROUND Traumatic hip dislocation usually occurs following high-velocity trauma.It is imperative that the dislocation be reduced in a timely manner,especially in a closed manner,as an orthopedic emergency.However,closed reduction can hardly be achieved in patients who also have ipsilateral lower extremity fractures.Herein,we focus on hip dislocation associated with ipsilateral lower extremity fractures,excluding intracapsular fractures(femoral head and neck fractures),present an early closed hip joint reduction method for this injury pattern,and review the literature to discuss the appropriate closed reduction technique for this rare injury pattern.CASE SUMMARY We report a case of a 37-year-old male who sustained a left acetabular posterior wall fracture,an ipsilateral comminuted subtrochanteric fracture and dislocation of the hip.The hip dislocation was reduced urgently in a closed manner using the joy-stick technique with a T-shaped Schanz screw.The fractures were reduced and fixed as a 2nd-stage surgery procedure.At the 17-month postoperative follow-up,the patient had full range of motion of the affected hip.CONCLUSION Closed reduction of a hip dislocation associated with ipsilateral lower extremity fractures is rarely achieved by regular maneuvers.Attempts at closed reduction,by means of indirectly controlling the proximal fracture fragment or reconstructing the femoral leverage rapidly with the aid of various external reduction apparatuses,were shown to be effective in some scenarios.Mandatory open reduction is indicated in cases of failed closed reduction,particularly in irreducible dislocations.
基金the China National Petroleum Corporation’s Forward-Looking Fundamental Technology Breakthrough Project(2021DJ2305).
文摘Self-suspended proppants,which enable clear-water fracturing,represent a promising new class of materials for reservoir stimulation.Given the economic limitations associated with their exclusive use,this study investigates proppant transport behavior in hybrid systems combining self-suspended proppants with conventional 40/70 mesh quartz sand at various mixing ratios.A dedicated experimental apparatus was developed to replicate field-relevant complex fracture networks,consisting of a main fracture and two branching fractures with different deflection angles.Using this system,sand bank formation and proppant distribution were examined for both conventional quartz sand fracturing and fracturing augmented with self-suspended proppants.The effects of slurry discharge volume,proppant mixing ratio,sand ratio,and injection location of the self-suspended proppant on transport and placement behavior were systematically analyzed.According to the results,the incorporation of self-suspended proppants markedly enhances the proppant-carrying capacity of the slurry and substantially modifies sand bank morphology.Increasing the discharge volume raises the inlet slope angle and promotes greater proppant penetration into branch fractures.The proportion of self-suspended proppant governs slurry viscoelasticity and,consequently,proppant settling behavior.As the fraction of self-suspended proppant decreases,the equilibrium height of the sand bank increases,while the proppant mass fraction within branch fractures exhibits a non-monotonic response,initially decreasing and then increasing.Variations in sand ratio alter both overall proppant concentration and the self-suspended proppant-to-water ratio,thereby modulating slurry rheology and influencing proppant placement.In addition,changes in injection location affect near-wellbore vortex structures,leading to distinct sand bank morphologies.
基金supported by the Major Science and Technology Project of Gansu Province(Grant No.24ZD13FA003 and 23ZDWA005)National Natural Science Foundation of China(Grant No.42371140,42301163,41971087 and 42272332)the program of the State Key Laboratory of Cryospheric Science and Frozen Soil Engineering,CAS(No.CSFSEZZ-2411)。
文摘In permafrost regions of the QinghaiXizang Plateau,embankments of the Qinghai-Xizang Highway and Qinghai-Xizang Railway experiencing roadside water accumulation exhibit more pronounced engineering deteriorations.A widely accepted view is that the accumulated water adjacent to the embankment possesses substantial thermal energy,which accelerates the degradation-even disappearance-of the underlying permafrost.Moreover,the presence of roadside water keeps the embankment soil in a persistently high-moisture state,thereby making the frozen-soil embankment more susceptible to deformation under traffic loading.However,in the permafrost regions of the QinghaiXizang Plateau,deteriorations of embankments affected by roadside water are more commonly manifested as undulating pavement surfaces,and extensive crack networks appear on the embankment crest even where thermosyphons are installed.These manifestations are not fully consistent with the deterioration mechanisms proposed by existing viewpoints.We propose the hypothesis that temperature gradients,formed due to the freezing and thawing processes between the roadside wateraffected soil and the roadbed soil,lead to moisture migration under the influence of temperature gradients,resulting in frost heave and thaw settlement in the roadbed soil.To validate this hypothesis,we conducted the following investigations sequentially.Initially,we selected a roadbed with a thermosyphon(TPCT)system,which has a significant cooling effect,as the study object.By analyzing the temperature monitoring data of the roadbed section,the temperature variance was calculated to identify the time nodes where the temperature gradient of the roadbed soil was maximum and minimum.Subsequently,corresponding roadbed temperature distribution maps were drawn,illustrating the changes in the temperature and position of the lowtemperature core near the TPCT over time.Furthermore,using small-scale indoor model experiments,we qualitatively concluded that moisture in the soil migrates toward the TPCT due to the temperature gradient.Thereafter,combining borehole water content data and precipitation data from the sloped terrain construction site,the formation mechanisms and timing characteristics of roadside water accumulation were analyzed.Ultimately,by integrating the ground temperature data,air temperature data,roadside water formation mechanisms,and the operating characteristics of the TPCT,it was concluded that roadside water,while in a thawed state during TPCT operation,acts as a supplementary source for moisture migration in the roadbed soil.This migration leads to cracking in the TPCT roadbed.Therefore,this study reveals a novel damage mechanism:asynchronous freeze-thaw processes induce temperature gradients,which drive the migration of roadside water into the roadbed and are responsible for the cracking damage.
基金the PICTO project(RFCR-CT-2018-800711)funded by the European Research Fund for Coal and Steel(RFCS)and the Polish Ministry of Science and Higher Education(W93/FBWiS/2018).
文摘The research presented in this paper aimed to analyze the evolution of fractures in strata in relation to the progress of longwall mining.To achieve this objective,an introscopic probe equipped with a highresolution camera was developed,along with additional equipment that enables continuous recording of the internal surfaces of drainage boreholes exceeding 100 m in depth.The probe was utilized to test two methane drainage boreholes in the Z-3b longwall,which operates within the 501/3 coal seam of the Jankowice mine in Poland.Automatic image analysis methods were applied to evaluate the recorded images,based on a newly developed classificationsystem for fractures categorized by size and number.The results were compared with an analysis of changes in the methane capture rate from the drainage boreholes,which correlated with longwall mining progress.A strong correlation was observed between the number of fractures and the lithology of the strata layers.The largest number of fractures and their evolution were recorded in the coal layers,followed by the shale layers,while the sandstone layers exhibited the least number of fractures.Based on parallel measurements of the methane capture rate from the drainage boreholes during the progress of longwall mining,the extent of the strata's fracture zone was determined to range from 6 m to 36 m.Within the fracture zone,the strata are highly fractured,which leads to an increase in methane emissions through seepage and diffusion processes.
文摘Hydraulic fracturing serves as a critical technology for reservoir stimulation in deep coalbed methane(CBM)development,where the mechanical properties of gangue layers exert a significant control on fracture propagation behavior.To address the unclear mechanisms governing fracture penetration across coal-gangue interfaces,this study employs the Continuum-Discontinuum Element Method(CDEM)to simulate and analyze the vertical propagation of hydraulic fractures initiating within coal seams,based on geomechanical parameters derived from the deep Benxi Formation coal seams in the southeastern Ordos Basin.The investigation systematically examines the influence of geological and operational parameters on cross-interfacial fracture growth.Results demonstrate that vertical stress difference,elastic modulus contrast between coal and gangue layers,interfacial stress differential,and interfacial cohesion at coal-gangue interfaces are critical factors governing hydraulic fracture penetration through these interfaces.High vertical stress differences(>3 MPa)inhibit interfacial dilation,promoting predominant crosslayer fracture propagation.Reduced interfacial stress contrasts and enhanced interfacial cohesion facilitate fracture penetration across interfaces.Furthermore,smaller elastic modulus contrasts between coal and gangue correlate with increased interfacial aperture.Finally,lower injection rates effectively suppress vertical fracture propagation in deep coal reservoirs.This study elucidates the characteristics and mechanisms governing cross-layer fracture propagation in coal–rock composites with interbedded partings,and delineates the dynamic evolution laws and dominant controlling factors involved.Thefindings provide critical theoretical insights for the optimization of fracture design and the efficient development of deep coalbed methane reservoirs.
基金The Vice Chancellor of Research and Technology at Urmia University。
文摘Background:Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure.Pedicle screws are primarily designed for internal fixation in spinal procedures.A key objec-tive of many orthopedic studies is to assess the biocompatibility of implants with bone and adjacent soft tissue.This study aims to evaluate the biocompatibility and effects of the Pedicle screw-Rod configuration as a novel external fixation method in canine tibial osteotomy.Methods:With ethics approval,eight healthy,intact male dogs,aged 10-12 months and weighing between 20 and 22 kg,underwent a minimally invasive medial tibial approach for surgical fixation of tibial osteotomy using a Pedicle screw-Rod configu-ration.Postoperative evaluations included ultrasound assessments at the osteotomy site and histological evaluations at the bone-screw interface.Results:B-mode ultrasound evaluation indicated healing progress at all osteotomy sites.The color Doppler examination revealed an initial increase in signals in the sur-rounding soft tissue during the first 4 weeks post-operation,followed by a decrease in signals within the adjacent soft tissue between the 5th and 8th weeks.During this latter period,the signals were primarily concentrated on the bone surface and the callus.The bone-screw interface at various screw sites exhibited similar histological changes,indicating effective integration of the newly formed woven bone into the screw threads.Conclusions:Fixation of non-articular tibial osteotomy with Pedicle screw-Rod con-figuration resulted in secondary bone healing,characterized by abundant callus for-mation and neovascularization.This implant demonstrated favorable biocompatibility with bone and surrounding soft tissue,without significant complications.
文摘Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with long bone fractures in the extremities admitted to Santai Hospital Affiliated to North Sichuan Medical College from January 2023 to January 2025 were included,including cases of upper extremity forearm fractures and lower extremity femoral and tibial fractures.The patients were evenly divided using a random number table,with the control group undergoing open reduction and internal fixation(ORIF)combined with autologous periosteum graft,and the observation group undergoing ORIF,autologous periosteum graft,and PRP injection.Surgical indicators,complication rates,excellent fracture healing rates,functional satisfaction,and joint range of motion were compared between the two groups.Results:The surgical indicators in the observation group were similar to those in the control group(p>0.05).The complication rate in the observation group was lower than that in the control group,while the excellent fracture healing rate and functional satisfaction were higher in the observation group(p<0.05).Conclusion:Autologous periosteum graft combined with PRP technology is safe and reliable for the treatment of long bone fractures in the extremities,with satisfactory clinical outcomes.
基金supported by the National Key Research and Development Program Young Scientist Project(Grant No.2024YFC2911000)the National Natural Science Foundation of China(Grant No.52474103)the Major Basic Research Project of the Natural Science Foundation of Shandong Province(Grant No.ZR2024ZD22).
文摘Internal structural defects in engineering rock masses vary in size,exhibit complex shapes,and are unevenly distributed.Dominant fractures within a rock mass often play a critical to its mechanical behavior,directly affecting the macromechanical properties and failure modes.These fractures affect the instability and failure of the surrounding rock,significantlyimpacting the overall stability of engineering structures.Herein,sand-powder three-dimensional(3D)printing technology was used to prepare rock-like specimens with internal fracture networks.Triaxial compression testing,post-failure fracture mapping,and fractal dimension analysis of the fracture surfaces were conducted to investigate the effects of dominant fracture angles on the strength and deformation of rocks with internal fracture networks under triaxial stress.The results indicate that the dominant fracture angle has a pronounced effect on the mechanical behavior of rock.With increasing angle,both compressive strength and elastic modulus exhibit an initial decline followed by an increase.Moreover,higher confiningpressure significantlyimproves the compressive strength of fractured rock.This enhancement weakens as the confiningpressure further increases.Moreover,with increasing confiningpressure,the differences between the maximum and minimum values of elastic moduli and lateral strain ratios in fractured rock gradually decrease.Thus,the impact of the dominant fracture angle on rock mass deformation decreases with increasing confiningpressure.This research elucidates the effects of dominant fracture angles on the mechanical and failure properties of complex fractured rock masses and the influenceof the confiningpressure on these relationships.It provides valuable theoretical insights and practical guidance for stability analyses in engineering rock masses.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFC3007102)the National Natural Science Foundation of China(Grant Nos.42477188 and 41925012).
文摘One of the key challenges for underground rock reservoirs is ensuring prevention of the unwanted fluid leakage through rock fracture networks during their service life.Microbial-induced calcium carbonate precipitation(MICP)technology has emerged as a promising bio-healing method for rock fractures with small apertures.In this study,a new“three-stage”injection strategy-based MICP(TS-MICP)bio-healing method was proposed,aiming to achieve a“three-high”performance that includes high bridging rate,high mechanical strength,and high homogeneity.A series of meter-scale rock fracture models were prepared to conduct TS-MICP grouting tests.Compared with the traditional injection strategy-based biohealing methods,the TS-MICP method significantly improved the bridging rate(32.1%e89.5%),mechanical properties(0.138e1.023 MPa),and homogeneity of CaCO_(3)precipitation(334.4%).Additionally,it achieved a higher material utilization rate(1.72 times higher),reducing the consumption of cementation solution(CS)by 258.8%,thereby demonstrating greater potential for field applications.The underlying mechanism for achieving high bridging rate and high homogeneity in CaCO_(3)precipitation can be attributed to the synergistic effects of the coupling injection strategy,which optimizes the advantages at each stage.In stage I,under the influence of gravity,the rapid flocculation and hydrogen bonding interactions of organic matter lead to formation of the dense and high-strength CaCO_(3)precipitation at the bottom using a low-concentration bacterial suspension(BS).This process establishes bridging steps along the wall sides for subsequent uniform CaCO_(3)precipitation.In stage II,concentrated BS is utilized to produce looser CaCO_(3)flocculation,which precipitates uniformly on the pre-existing bridging steps.In stage III,a two-step injection strategy was employed to reinforce the loose CaCO_(3)crystals formed in stages I and II,and finally forms a strong bridging effect with“three-high”performance.
基金The National Natural Science Foundation of China(No.60603047)the Natural Science Foundation of Liaoning ProvinceLiaoning Higher Education Research Foundation(No.2008341)
文摘A new algorithm based on an FC-tree （frequent closed pattern tree） and a max-FCIA （maximal frequent closed itemsets algorithm） is presented, which is used to mine the frequent closed itemsets for solving memory and time consuming problems. This algorithm maps the transaction database by using a Hash table,gets the support of all frequent itemsets through operating the Hash table and forms a lexicographic subset tree including the frequent itemsets.Efficient pruning methods are used to get the FC-tree including all the minimum frequent closed itemsets through processing the lexicographic subset tree.Finally,frequent closed itemsets are generated from minimum frequent closed itemsets.The experimental results show that the mapping transaction database is introduced in the algorithm to reduce time consumption and to improve the efficiency of the program.Furthermore,the effective pruning strategy restrains the number of candidates,which saves space.The results show that the algorithm is effective.
文摘BACKGROUND In pediatric age group patients(<18 years old)treated operatively for distal radius/both bone fractures extending imaging beyond the initial postoperative period-particularly in uncomplicated cases-appears to provide limited additional benefit.AIM To determine the necessary number of follow-up X-rays to use resources efficiently.METHODS Participants included in this study are pediatric age group patients who were treated operatively for distal radius/both bone fractures and were identified from a prospected collected data from the operating room database between the years 2009 and 2017.The data in the study included patients who had distal radius fractures and underwent fixation surgery(n=88).RESULTS When assessing the difference in the odds of conducting 1 or less X-ray compared to 2 or more X-rays in regard to the type of fixation,the only significant difference is the closed reduction fixation method.Patients who underwent closed reduction method procedure have significantly lower odds of having 2 more X-rays compared to those who didn’t have closed reduction method.Open reduction,internal fixation,and other fixation methods(close reduction and internal fixation,debridement,or epiphysiodesis)have higher odds of having two or more X-rays compared to patients who did not receive these methods;however,these odds are not statistically significant.CONCLUSION The findings of this study reveal notable absence of a statistically significant association between the frequency of postoperative X-rays and the outcome of children with distal radius fractures.
