Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscal...Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscale to the rock matrix,and traditional algorithms have difficulty to achieve accurate segmentation results.In this study,a dataset containing multiscale fracture information was constructed,and a U-Net semantic segmentation model with a scSE attention mechanism was used to classify shale CT images at the pixel level and compare the results with traditional methods.The results showed that the CLAHE algorithm effectively removed noise and enhanced the fracture information in the dark parts,which is beneficial for further fracture extraction.The Canny edge detection algorithm had significant false positives and failed to recognize the internal information of the fractures.The Otsu algorithm only extracted fractures with a significant difference from the background and was not sensitive enough for fine fractures.The MEF algorithm enhanced the edge information of the fractures and was also sensitive to fine fractures,but it overestimated the aperture of the fractures.The U-Net was able to identify almost all fractures with good continuity,with an MIou and Recall of 0.80 and 0.82,respectively.As the image resolution increases,more fine fracture information can be extracted.展开更多
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 Shoulder injuries caused by trauma are common,including clavicle fractures.Even so,bipolar segmental fracture of the clavicle is extremely rare and seldom reported.Therefore,there is still a controversial i...BACKGROUND Shoulder injuries caused by trauma are common,including clavicle fractures.Even so,bipolar segmental fracture of the clavicle is extremely rare and seldom reported.Therefore,there is still a controversial issue about how to treat these bipolar segmental clavicle fractures.CASE SUMMARY A 56-year-old security guard arrived at our emergency room after falling on his electric bicycle.There was no loss of consciousness or other pain.He had no numbness in his fingers.X-rays and 3D computed tomography revealed that the patient’s right shoulder had a bipolar segmental clavicle fracture.The surgical procedure included both open reduction and internal fixation.At the 1-year follow-up,he had a full range of motion and minimal discomfort in the injured shoulder.CONCLUSION We provide a rare case of bipolar clavicle facture in the right clavicle.We hold the opinion that such patients would get better clinical and radiological outcomes by early and correct operation.展开更多
With the rapid development of shale gas exploration and development in China,casing deformation in shale gas horizontal wells happens frequently,which directly impacts the development efficiency and benefits of shale ...With the rapid development of shale gas exploration and development in China,casing deformation in shale gas horizontal wells happens frequently,which directly impacts the development efficiency and benefits of shale gas.In order to explore casing deformation prediction,prevention and treatment methods,this paper analyzes the geological and engineering causes of casing deformation in shale-gas horizontal wells through laboratory work,such as the casing resistance to internal pressure alternating test,the ground simulation test and systematical casing deformation characteristic analysis of MIT24 caliper logging,and the large-scale physical simulation test and numerical simulation of casing deformation.Then,combined with the generalized shear activity criterion,a new method for evaluating casing deformation risk points and some technical measures for preventing casing deformation were formulated.And the following research results were obtained.First,the deformation characteristics of 119 casing deformation points in 23 wells interpreted by MIT24 caliper logging are consistent with the mechanical behaviors of shear compression deformation test.Second,the large-scale physical simulation test shows that natural fault-fractures slip obviously under the state of strike-slip stress.Third,numerical simulation shows that the compression stress on casing increases with the increase of fault-fracture slip.When the fault-fracture slip is between 7.5 mm and 9.0 mm,the casing reaches the critical yield strength and begins to undergo plastic deformation.The“temporary fracture plugging+long segment and multi-cluster”and other technologies are field tested in 28 wells in Weiyuan area of southern Sichuan Basin.The casing deformation rate decreases from 54%(before this research)to 14.3%,and the segment loss rate decreases from 7.8%to 0,which reveals remarkable achievements in casing deformation treatment.In conclusion,the shear slip of fault and macro fractures(referred to as fault-fracture)is the main cause of casing deformation in shale gas horizontal wells,and some measures(e.g.“temporary fracture plugging+long segment and multi-cluster”,reducing fracturing scale and releasing wellbore pressure properly)shall be taken in advance to reduce the fault-fracture activity before the risk point of casing deformation is fractured,so as to reach the goal of casing deformation prevention.展开更多
Purpose： To compare the outcomes of closed reduction and expert tibial nailing （ETN） versus open reduction and plate and screw fixation in treating two segmental tibial fractures. Methods： This study included 53 c...Purpose： To compare the outcomes of closed reduction and expert tibial nailing （ETN） versus open reduction and plate and screw fixation in treating two segmental tibial fractures. Methods： This study included 53 cases of two segmental fractures of the tihial shaft. They were admitted to our department between March 2010 and June 2013 and treated respectively by closed reduction and ETN （ETN group, n = 31 ） or open reduction fixation with plate and screws （PS group, n = 22）. The general data of two groups including gender, age, injury cause, fracture type, etc showed no significant difference （p 〉 0.05）. To compare the therapeutic effects between two groups, the intraoperative condition, post- operative function and related complications were investigated. Results： All the patients were successfully followed up. The period was 19.2 months for ETN group and 20.5 months for PS group. All the fractures in ETN group had union without complications such as malunion, infection, or osteofascial compartment syndrome; whereas there were 3 cases of superficial infection cured by repeated dressing change and 2 cases of delayed union in PS group. The total incidence of complication in PS group was 22.7% （5/22）, much higher than that in ETN group （p 〈 0.05）. Moreover, ETN group showed a better result in terms of intraoperative blood loss, operation time, postoperative weight bearing time and fracture union time. In ETN group, at one-year follow-up, Johner-Wruhs＇ criteria was adopted to assess the postoperative function, which was reported as excellent in 18 cases, good in 10 cases and fair in 3 cases in ETN group （100% excellent-good rate）. While in PS group, the result was excellent in 10 cases, good in 7 cases, fair in 3 cases and poor in 2 cases （77.3% excellent-good rate）. The comparison was insignificant （p 〉 0.05）. Conclusion： Compared with plate and screw fixation, ETN fixation has the advantages of fewer complications, shorter operation time, being less invasive, earlier postoperative rehabilitation and weight bearing, quicker fracture union and better functional recovery, thus being an effective way to treat two segmental tibial fractures.展开更多
基金funded by the Natural Science Basis Research Plan in Shaanxi Province of China(No.2022JM-147).
文摘Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response analysis.However,fractures in CT images are similar in grayscale to the rock matrix,and traditional algorithms have difficulty to achieve accurate segmentation results.In this study,a dataset containing multiscale fracture information was constructed,and a U-Net semantic segmentation model with a scSE attention mechanism was used to classify shale CT images at the pixel level and compare the results with traditional methods.The results showed that the CLAHE algorithm effectively removed noise and enhanced the fracture information in the dark parts,which is beneficial for further fracture extraction.The Canny edge detection algorithm had significant false positives and failed to recognize the internal information of the fractures.The Otsu algorithm only extracted fractures with a significant difference from the background and was not sensitive enough for fine fractures.The MEF algorithm enhanced the edge information of the fractures and was also sensitive to fine fractures,but it overestimated the aperture of the fractures.The U-Net was able to identify almost all fractures with good continuity,with an MIou and Recall of 0.80 and 0.82,respectively.As the image resolution increases,more fine fracture information can be extracted.
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 Shoulder injuries caused by trauma are common,including clavicle fractures.Even so,bipolar segmental fracture of the clavicle is extremely rare and seldom reported.Therefore,there is still a controversial issue about how to treat these bipolar segmental clavicle fractures.CASE SUMMARY A 56-year-old security guard arrived at our emergency room after falling on his electric bicycle.There was no loss of consciousness or other pain.He had no numbness in his fingers.X-rays and 3D computed tomography revealed that the patient’s right shoulder had a bipolar segmental clavicle fracture.The surgical procedure included both open reduction and internal fixation.At the 1-year follow-up,he had a full range of motion and minimal discomfort in the injured shoulder.CONCLUSION We provide a rare case of bipolar clavicle facture in the right clavicle.We hold the opinion that such patients would get better clinical and radiological outcomes by early and correct operation.
基金supported by the Scientific Research and Technology Development Project of CNPC“Research and field test of key technologies for effective exploitation of deep shale gas”(No.2019F-31JT).
文摘With the rapid development of shale gas exploration and development in China,casing deformation in shale gas horizontal wells happens frequently,which directly impacts the development efficiency and benefits of shale gas.In order to explore casing deformation prediction,prevention and treatment methods,this paper analyzes the geological and engineering causes of casing deformation in shale-gas horizontal wells through laboratory work,such as the casing resistance to internal pressure alternating test,the ground simulation test and systematical casing deformation characteristic analysis of MIT24 caliper logging,and the large-scale physical simulation test and numerical simulation of casing deformation.Then,combined with the generalized shear activity criterion,a new method for evaluating casing deformation risk points and some technical measures for preventing casing deformation were formulated.And the following research results were obtained.First,the deformation characteristics of 119 casing deformation points in 23 wells interpreted by MIT24 caliper logging are consistent with the mechanical behaviors of shear compression deformation test.Second,the large-scale physical simulation test shows that natural fault-fractures slip obviously under the state of strike-slip stress.Third,numerical simulation shows that the compression stress on casing increases with the increase of fault-fracture slip.When the fault-fracture slip is between 7.5 mm and 9.0 mm,the casing reaches the critical yield strength and begins to undergo plastic deformation.The“temporary fracture plugging+long segment and multi-cluster”and other technologies are field tested in 28 wells in Weiyuan area of southern Sichuan Basin.The casing deformation rate decreases from 54%(before this research)to 14.3%,and the segment loss rate decreases from 7.8%to 0,which reveals remarkable achievements in casing deformation treatment.In conclusion,the shear slip of fault and macro fractures(referred to as fault-fracture)is the main cause of casing deformation in shale gas horizontal wells,and some measures(e.g.“temporary fracture plugging+long segment and multi-cluster”,reducing fracturing scale and releasing wellbore pressure properly)shall be taken in advance to reduce the fault-fracture activity before the risk point of casing deformation is fractured,so as to reach the goal of casing deformation prevention.
文摘Purpose： To compare the outcomes of closed reduction and expert tibial nailing （ETN） versus open reduction and plate and screw fixation in treating two segmental tibial fractures. Methods： This study included 53 cases of two segmental fractures of the tihial shaft. They were admitted to our department between March 2010 and June 2013 and treated respectively by closed reduction and ETN （ETN group, n = 31 ） or open reduction fixation with plate and screws （PS group, n = 22）. The general data of two groups including gender, age, injury cause, fracture type, etc showed no significant difference （p 〉 0.05）. To compare the therapeutic effects between two groups, the intraoperative condition, post- operative function and related complications were investigated. Results： All the patients were successfully followed up. The period was 19.2 months for ETN group and 20.5 months for PS group. All the fractures in ETN group had union without complications such as malunion, infection, or osteofascial compartment syndrome; whereas there were 3 cases of superficial infection cured by repeated dressing change and 2 cases of delayed union in PS group. The total incidence of complication in PS group was 22.7% （5/22）, much higher than that in ETN group （p 〈 0.05）. Moreover, ETN group showed a better result in terms of intraoperative blood loss, operation time, postoperative weight bearing time and fracture union time. In ETN group, at one-year follow-up, Johner-Wruhs＇ criteria was adopted to assess the postoperative function, which was reported as excellent in 18 cases, good in 10 cases and fair in 3 cases in ETN group （100% excellent-good rate）. While in PS group, the result was excellent in 10 cases, good in 7 cases, fair in 3 cases and poor in 2 cases （77.3% excellent-good rate）. The comparison was insignificant （p 〉 0.05）. Conclusion： Compared with plate and screw fixation, ETN fixation has the advantages of fewer complications, shorter operation time, being less invasive, earlier postoperative rehabilitation and weight bearing, quicker fracture union and better functional recovery, thus being an effective way to treat two segmental tibial fractures.
