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Heterotopic ossification after arthroscopy for hip impingement syndrome

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Chinese Medical Journal 2019年第7期132卷 827-833页

作者： Guan-Ying Gao Xin Zhang Ling-Hui Dai Hong-Jie Huang Rui-Qi Wu Xiao-Dong Ju Yu Mei Xing-Yue Niu Jian-Quan Wang Yan Xu Institute of Sports Medicine Beijing Key Laboratory of Sports InjuriesPeking University Third HospitalBeijing 100191China

Background:Heterotopic ossification(HO)is a known complication of hip arthroscopy.We investigated incidence of HO after hip arthroscopy and determined whether revision for HO improved outcome.Methods:A retrospective study was conducted on 242 patients(140 men and 102 women,mean age:36.2±9.5 years)who underwent hip arthroscopy for femoroacetabular impingement(FAI)between January 2016 and January 2018.The average followup period was 22.88±11.74 months(range:11-34 months).Thirteen(5.37%)cases of HO(six men and seven women,five left hips and eight right hips;mean age:37.5±4.7 years)were observed.Among them,four cases with HO with obvious pain symptoms and persistent non-remission underwent revision surgery to remove HO.Monthly follow-up was conducted.Visual analog scale(VAS),modified Harris Hip Score(mHHS),and non-Arthritis Hip Score(NAHS)were evaluated and compared between HO and non-HO patients.Independent sample t test,Mann-Whitney U test and the Chi-square test were used for inter-group comparisons.HO degree was evaluated using Brooker classification.Symptoms and function were evaluated before and after revision.Results:A total of 242 patients were involved in this study.Thirteen cases(5.4%)had imaging evidence of HO.Nine(9/13)were classified as Brooker stageⅠ,three(3/13)Brooker stageⅡ,and one(1/13)Brooker stageⅢ.HO was detected by ultrasonography as early as 3 weeks after operation.After primary surgery,the mHHS of the HO group and non-HO group increased by 13.00(8.50,25.50)and 24.00(14.00,34.50)points(Z=-1.80,P=0.08),NAHS increased by 18.00(9.50,31.50)and 26.00(13.50,36.00)points(Z=-1.34,P=0.18),and VAS decreased by 3.00(2.00,4.00)and 4.00(3.00,4.50)points(Z=-1.55,P=0.12).Average follow-up time after revision was 9.00±2.94 months;mHHS increased by 34.75 points t=-55.23,P<0.01)and NAHS by 28.75 points t=-6.03,P<0.01),and VAS decreased by 4 points t=9.80,P<0.01).HO and non-HO patients were similar for demographic and surgical data,and clinical and functional scores.Conclusion:HO incidence after arthroscopic treat

关键词： Heterotopic ossification Hip Arthroscopy Femoroacetabular impingement

Eliminating impingement optimizes patellar biomechanics in high knee flexion

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Chinese Medical Journal 2010年第16期123卷 2244-2248页

作者： TANG Qi-heng ZHOU Yi-xin TANG Jing SHAO Hong-yi WANG Guang-zhi Department of Orthopaedic Surgery Beijing Jishuitan HospitalFourth Clinical College of Peking University Beijing 100035China Department of Biomedical Engineering Tsinghua UniversityBeijing 100084 China

Background We investigated the impact of eliminating the impingement between extensor mechanism and tibial insert on patellar tracking and patellar ligament tension in high knee flexion.Methods Six cadaveric specimens were tested on an Oxford-type testing rig.The Genesis Ⅱ knee system was implanted into each specimen knee with the traditional tibial insert and high-flex insert successively.Compared to traditional insert, the high-flex insert was characterized with a chamfered anterior post and a chamfered anterior lip which eliminates patella-post and patellar ligament-anterior lip impingements.The patella was tracked with an NDI Optotrak Certus system.The patellar ligament tension was measured using a NKB S-type tension transducer.Results There was a decrease of resultant patellar translation relative to the femur with statistically significant （P 〈0.05）at 90° to 150° of knee flexion and a decrease of patellar ligament tension with statistical significance （P 〈0.05） at 100°,120°, 130°, and 140° of flexion using high-flex insert compared to traditional insert.Conclusions Eliminating the impingement between extensor mechanism and implant in high knee flexion altered patellar tracking and reduced patellar ligament tension, which would facilitate high knee flexion.

关键词： extensor mechanism impingement patella biomechanics

Numerical Approach to Film Cooling Effectiveness Over a Plate Surface with Coolant impingement

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Journal of Thermal Science 2004年第1期13卷 67-74页

作者： Chang-Hsien Tai Jr-Ming Miao A-Fu Kao Department of Vehicles Engineering National Pingtung University of Science and TechnologyPingtungTaiwanChinaDepartment of Mechanical EngineeringChung Cheng Institute of TechnologyNational Defense UniversityTaoyuanTaiwanChinaGraduate School of Defense Science StudiesChung Cheng Institute of TechnologyNational Defense UniversityTaoyuanTaiwanChina

The aim of the present study is conducting the numerical approach to a combination of internal jet impingement and external film cooling over a flat plate. A multi-block three-dimensional Navier-Stokes code, CFX 4.4, with k-e turbulence model is used to simulate this complicated thermal-flow structure induced by the interaction of coolant jet and hot cross mainstream. By assuming the adiabatic wall boundary condition on the tested film-cooled plate, both the local and the spanwise-averaged adiabatic film cooling effectiveness are evaluated for comparison of the cooling performance at blowing ratios of Br=0.5, 1.0, and 1.5. Film flow data were obtained from a row of five cylindrical film cooling holes, inclined in angle of 35?and 0?in direction of streamwise and spanwise, respectively. The film cooling hole spacing between adjacent holes is 15 mm for all the holes. Before the coolant flow being injected through individual cooling hole then encountered with the mainstream, an impingement chamber containing an impingement plate with 43 holes is located on the path of coolant flow. Present study also focused on the effect of impingement spacing, 10mm, 20mm, and 30mm. Compare the results, we find the impingement jet has a significant effect on the adiabatic film cooling effectiveness. As the coolant impingement spacing is fixed, results indicated that higher blowing ratio would enhance the local and the spanwise-averaged adiabatic film cooling effectiveness. Moreover, neither uniform nor parabolic distribution of pressure distribution are observed within the coolant hole-pipe.

关键词： film cooling impingement cooling CFD turbulence model.

Study of coupled effect of impingement jet cooling of kerosene with solid structure

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Science China(Technological Sciences) 2019年第11期62卷 2021-2028页

作者： DU MengMeng ZHONG FengQuan XING YunFei ZHANG XinYu State Key Laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Characteristics of flow and heat transfer of kerosene impingement jets were studied numerically.The coupled effect of heat transfer of fluid and structure was investigated.Numerical simulation of fluid flow shows that compared to convective heat transfer of kerosene flow in cooling channels,impingement jet cooling significantly enhances heat transfer ability.At the same time,the pressure loss is below one atmospheric pressure.Both stress and strain of high temperature nickle-based alloy structure were analyzed with typical thermal loading and impingement cooling effect.The numerical results show that temperature distribution in the hot surface of the solid structure is relatively uniform and far below the maximum allowable temperature of the alloy material.The strength analysis shows that both stress and strain of the solid structure meet the material requirements.

关键词： impingement jet cooling hydrocarbon fuel heat transfer enhancement fluid-solid coupling

Experimental study of single-row chevron-jet impingement heat transfer on concave surfaces with different curvatures

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Chinese Journal of Aeronautics 2019年第10期32卷 2275-2285页

作者： Yuanwei LYU Jingzhou ZHANG Xichen LIU Yong SHAN Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

To address the curvature effect on single-row chevron-nozzle jet impingement heat transfer on concave surface,a series of experiments are conducted in the present investigation.Four concave surfaces including one semi-cylindrical concave surface and three parabolic concave surfaces with different width-to-depth ratios are tested under three typical Reynolds numbers(Re=5000,10000 and 15000)and several dimensionless nozzle-to-surface distances ranging from 1 to 8.The results show that the concave curvature has a clear impact on chevron-nozzle jet impingement heat transfer,tightly dependent on jet Reynolds number and impinging distance.In general,the semicylindrical concave surface produces the highest longitudinally-averaged Nusselt number at the leading line of concave surface.Under a low jet Reynolds number,the parabolic concave surface with a highly curved curvature produces higher longitudinally-averaged Nusselt number at the leading line and more uniform longitudinally-averaged Nusselt number distribution along the curvilinear direction.However,the longitudinally-averaged Nusselt number at the leading line of concave surface is the lowest for the highly curved surface under a high jet Reynolds number and large impinging distance.In comparison with the round-nozzle,chevron nozzle plays a more significant role on improving jet impingement heat transfer at small impinging distances.

关键词： Chevron nozzle Concave surface Experimental test Heat transfer Jet impingement

Numerical Simulation of Jet Behavior and impingement Characteristics of Preheating Shrouded Supersonic Jets

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Journal of Iron and Steel Research(International) 2016年第10期23卷 997-1006页

作者： Guang-sheng WEI Rong ZHU Ting CHENG Fei ZHAO School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Key Laboratory of Research Center of Special Melting and Preparation of High-end Metal Materials University of Science and Technology Beijing National Center for Materials Service Safety University of Science and Technology Beijing

As a novel supersonic jet technology,preheating shrouded supersonic jet was developed to deliver oxygen into molten bath efficiently and affordably.However,there has been limited research on the jet behavior and impingement characteristics of preheating shrouded supersonic jets.Computational fluid dynamics（CFD）models were established to investigate the effects of main and shrouding gas temperatures on the characteristics of flow field and impingement of shrouded supersonic jet.The preheating shrouded supersonic jet behavior was simulated and measured by numerical simulation and jet measurement experiment respectively.The influence of preheating shrouded supersonic jet on gas jet penetration and fluid flow in liquid bath was calculated by the CFD model which was validated against water model experiments.The results show that the uptrend of the potential core length of shrouded supersonic jet would be accelerated with increasing the main and shrouding gas temperatures.Also,preheating supersonic jets demonstrated significant advantages in penetrating and stirring the liquid bath.

关键词： shrouded supersonic jet preheating gas temperature jet behavior impingement flow field

Femoroacetabular impingement with chronic acetabular rim fracture- 3D computed tomography, 3D magnetic resonance imaging and arthroscopic correlation

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World Journal of Orthopedics 2015年第6期6卷 498-504页

作者： Avneesh Chhabra Shaun Nordeck Vibhor Wadhwa Sai Madhavapeddi William J Robertson Department of Radiology University of Texas Southwestern Medical Center Department of Orthopaedics University of Texas Southwestern Medical Center

Femoroacetabular impingement is uncommonly associated with a large rim fragment of bone along the superolateral acetabulum. We report an unusual case of femoroacetabular impingement(FAI) with chronic acetabular rim fracture. Radiographic, 3D computed tomography, 3D magnetic resonance imaging and arthroscopy correlation is presented with discussion of relative advantages and disadvantages of various modalities in the context of FAI.

关键词： 3D computed tomography 3D magnetic resonance imaging Femoroacetabular impingement Rim fracture

Posterior ankle impingement–an underdiagnosed cause of ankle pain in pediatric patients

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World Journal of Orthopedics 2019年第10期10卷 364-370页

作者： Indranil Kushare Kristen Kastan Sachin Allahabadi Department of Orthopaedics Texas Children’s hospitalThe WoodlandsTX 77384United States Department of Orthopaedics University of CaliforniaSan FranciscoCA 94143United States

BACKGROUND Posterior ankle impingement syndrome(PAIS)is a cause of ankle pain due to pinching of bony or soft tissue structures in the hindfoot.The diagnosis is primarily made based on detailed history and accurate clinical examination.The delay in its diagnosis has not yet been described in the pediatric and adolescent population.AIM To identify and characterize misdiagnosed cases of PAIS in pediatric and adolescent patients.METHODS This descriptive prospective study at a tertiary children’s hospital included patients≤18 years who underwent posterior ankle arthroscopy after presenting with chronic posterior ankle pain after being diagnosed with PAIS.Collected data included:Demographics,prior diagnoses and treatments,providers seen,time to diagnosis from presentation,and prior imaging obtained.Visual Analogue Scale(VAS)for pain and American Orthopedic Foot Ankle Society(AOFAS)ankle-hindfoot scores were noted at initial presentation and follow-up.RESULTS 35 patients(46 ankles)with average age of 13 years had an average 19 mo(range 0-60 mo)delay in diagnosis from initial presentation.25(71%)patients had previously seen multiple medical providers and were given multiple other diagnoses.All 46(100%)ankles had tenderness to palpation over the posterior ankle joint.Radiographs were reported normal in 31/42(72%)exams.In 32 ankles who underwent MRI,the most common findings included os trigonum(47%)/Stieda process(47%).Conservative treatment had already been attempted in all patients.Ankle impingement pathology was confirmed during arthroscopy in 46(100%)ankles.At an average follow-up of 13.1 mo,there was an improvement of VAS(pre-op 7.0 to post-op 1.2)and AOFAS scores(pre-op 65.1 to post-op 94).CONCLUSION This is the first study which shows that PAIS is a clinically misdiagnosed cause of posterior ankle pain in pediatric and adolescent population;an increased awareness about this diagnosis is needed amongst providers treating young patients.

关键词： Ankle impingement Ankle pain Os trigonum Delayed diagnosis Ankle arthroscopy Pediatric

Analyses of possible risk factors for subacromial impingement syndrome

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World Journal of Orthopedics 2012年第1期3卷 5-9页

作者： Boonsin Tangtrakulwanich Anucha Kapkird Department of Orthopaedic Surgery Faculty of Medicine Prince of Songkla University Hat Yai Songkhla 90110 Thailand

AIM: To evaluate the association between various risk factors, including sleeping position, and impingement syndrome. impingement syndrome is the most common cause of shoulder problems. The pathogenesis of this problem is still debated these days.METHODS: This was a case control study conducted at the outpatient clinic of Songklanakarind hospital. Data regarding history, physical examination and radiographic evaluations using supraspinatous outlet views were obtained from all patients with clinically suspected impingement syndrome. The diagnoses of impingement syndrome were confirmed by a xylocaine subacromial injection test. All patients were interviewed concerning their usual sleeping position, which was categorized into supine, decubitus, prone and undetermined. Radiographs were evaluated to determine the shape of the acromion, which was divided into 3 types: flat, curved and hook. We used logistic regression analysis to determine the association between risk factors and outcome.RESULTS: The study group included 111 patients with impingement syndrome and 191 healthy volunteers as a control group. The mean age was about 50 years with a body mass index(BMI) of 24 kg/m2 in both groups. The most common shape of the acromion was flat(84.5%), followed by curved(10.7%) and hook(4.8%). We found the 4 independent risk factors affecting impingement syndrome were smoking status, occupation, acromion shape and sleeping position. Patients who currently smoked had a 6.8 times greater risk of impingement syndrome compared to non-smokers(OR 6.8, 95% CI: 1.2-39) and government officers had a 6.3 times increased risk compared to rubber tappers(OR 6.3, 95% CI: 1.3-30.3). Patients with a hook type acromion had 6.2 times the risk of flat type(OR 6.2, 95% CI: 1.1-35) and patients who slept in the decubitus position had 3.7 times the risk of those who slept in the supine position(OR 3.7, 95% CI: 1.2-11.6). No significant associations were found between age, sex, BMI, sports activity and impingement syndrome.CONCLUSION: Independent r

关键词： Smoking Decubitus impingement syndrome