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Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jian-Feng Chen 《Open Journal of Radiology》 2024年第1期14-23,共10页
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions... Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age. 展开更多
关键词 ANISOTROPY trabecular bone Score bone Mineral Density Ultra-Distal Radius Digital X-Ray Image
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Age- and direction-related adaptations of lumbar vertebral trabecular bone with respect to apparent stiffness and tissue level stress distribution 被引量:2
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作者 He Gong Yubo Fan +1 位作者 Ming Zhang Ling Qin 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第1期121-129,共9页
The objective of this study was to study the age-related adaptation of lumbar vertebral trabecular bone at the apparent level, as well as the tissue level in three orthogonal directions. Ninety trabecular specimens we... The objective of this study was to study the age-related adaptation of lumbar vertebral trabecular bone at the apparent level, as well as the tissue level in three orthogonal directions. Ninety trabecular specimens were obtained from six normal L4 vertebral bodies of six male cadavers in two age groups, three aged 62 years and three aged 69 years, and were scanned using a high-resolution micro-computed tomography (micro-CT) system, then converted to micro- finite element models to do micro-finite element analyses. The relationship between apparent stiffness and bone volume fraction, and the tissue level yon Mises stress distribution for each trabecular specimen when compressed separately in the longitudinal direction, medial-lateral and anterior-posterior directions (transverse directions) were derived and compared between two age groups. The results showed that at the apparent level, trabecular bones from 69-year group had stiffer bone structure relative to their volume fractions in all three directions, and in both age groups, changes in bone volume fraction could explain more variations in apparent stiffness in the longitudinal direction than the transverse directions; at the tissue level, aging had little effect on the tissue von Mises stress distributions for the compressions in all the three directions. The novelty of the present study was that it provided quantitative assessments on the age and direction- related adaptation of Chinese male lumbar vertebral trabecular bone from two different levels: stiffness at the apparent level and stress distribution at the tissue level. It may help to understand the failure mechanisms and fracture risks of vertebral body associated with aging and direction for the prevention of fracture risks in elder individuals. 展开更多
关键词 Vertebral body trabecular bone Micro-finite element analysis Apparent stiffness Tissuevon Mises stress
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Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice 被引量:1
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作者 Chandrasekhar Kesavan Nikita M Bajwa +1 位作者 Heather Watt Subburaman Mohan 《Bone Research》 SCIE CAS CSCD 2017年第4期357-366,共10页
To evaluate the long-term consequence of repetitive mild traumatic brain injury (mTBI) on bone, mTBI was induced in 10-week-old female C57BL/6J mice using a weight drop model, once per day for 4 consecutive days at ... To evaluate the long-term consequence of repetitive mild traumatic brain injury (mTBI) on bone, mTBI was induced in 10-week-old female C57BL/6J mice using a weight drop model, once per day for 4 consecutive days at different drop heights (0.5, 1 and 1.5 m) and the skeletal phenotype was evaluated at different time points after the impact. In vivo micro-CT (μ-CT) analysis of the tibial metaphysis at 2, 8 and 12 weeks after the impact revealed a 5%-32% reduction in trabecular bone mass. Histomorphometric analyses showed a reduced bone formation rate in the secondary spongiosa ofl.5 m impacted mice at 12 weeks post impact. Apparent modulus (bone strength), was reduced by 30% (P 〈 0.05) at the proximal tibial metaphysis in the 1.5 m drop height group at 2 and 8 weeks post impact. Ex vivo μ-CT analysis of the fifth lumbar vertebra revealed a significant reduction in trabecular bone mass at 12 weeks of age in all three drop height groups. Serum levels of osteocalcin were decreased by 22%, 15%, and 19% in the 0.5, 1.0 and 1.5 m drop height groups, respectively, at 2 weeks post impact. Serum IGF-I levels were reduced by 18%-32% in mTBI mice compared to control mice at 2 weeks post impact. Serum osteocalcin and IGF-I levels correlated with trabecular BV/TV (r2 = 0.14 and 0.16, P 〈 0.05). In conclusion, repetitive mTBI exerts significant negative effects on the trabecular bone microarchitecture and bone mechanical properties by influencing osteoblast function via reduced endocrine IGF-I actions. 展开更多
关键词 IGF TBI Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice
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Numerical simulation on the adaptation of forms in trabecular bone to mechanical disuse and basic multi-cellular unit activation threshold at menopause
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作者 He Gong Yubo Fan Ming Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第2期207-214,共8页
The objective of this paper is to identify the effects of mechanical disuse and basic multi-cellular unit (BMU) activation threshold on the form of trabecular bone during menopause. A bone adaptation model with mech... The objective of this paper is to identify the effects of mechanical disuse and basic multi-cellular unit (BMU) activation threshold on the form of trabecular bone during menopause. A bone adaptation model with mechanical- biological factors at BMU level was integrated with finite element analysis to simulate the changes of trabecular bone structure during menopause. Mechanical disuse and changes in the BMU activation threshold were applied to the model for the period from 4 years before to 4 years after menopause. The changes in bone volume fraction, trabecular thickness and fractal dimension of the trabecular structures were used to quantify the changes of trabecular bone in three different cases associated with mechanical disuse and BMU activation threshold. It was found that the changes in the simulated bone volume fraction were highly correlated and consistent with clinical data, and that the trabecular thickness reduced signi-ficantly during menopause and was highly linearly correlated with the bone volume fraction, and that the change trend of fractal dimension of the simulated trabecular structure was in correspondence with clinical observations. The numerical simulation in this paper may help to better understand the relationship between the bone morphology and the mecha-nical, as well as biological environment; and can provide a quantitative computational model and methodology for the numerical simulation of the bone structural morphological changes caused by the mechanical environment, and/or the biological environment. 展开更多
关键词 DISUSE ACTIVATION trabecular bone MENOPAUSE Functional adaptation
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Microstructure-based Finite Element Modelling and Characterisation of Bovine Trabecular Bone
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作者 R. Akhtar S. J. Eichhorn P. M. Mummery 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第1期3-9,共7页
The mechanical behaviour of trabecular bone is dependent on both the properties of individual trabeculae as well as their three-dimensional arrangement in space. In this study, nanoindentation was used to determine tr... The mechanical behaviour of trabecular bone is dependent on both the properties of individual trabeculae as well as their three-dimensional arrangement in space. In this study, nanoindentation was used to determine trabecular stiffness of bovine bone, both dehydrated and rehydrated. Values of 18.3 GPa and 14.3 GPa were obtained for dehydrated and rehydrated trabeculae respectively. These values were then used for finite element analysis where the mesh was generated directly from an X-ray microtomography dataset. The relationship between intrinsic tissue properties and apparent stiffness was explored. Moreover, the important role of collagen in bone micromechanics was demonstrated by complementing the study with Raman spectroscopy. 展开更多
关键词 trabecular bone NANOINDENTATION X-ray microtomography finite element modelling
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Osteoporosis Prediction for Trabecular Bone using Machine Learning: A Review
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作者 Marrium Anam Vasaki a/p Ponnusamy +4 位作者 Muzammil Hussain Muhammad Waqas Nadeem Mazhar Javed Hock Guan Goh Sadia Qadeer 《Computers, Materials & Continua》 SCIE EI 2021年第4期89-105,共17页
Trabecular bone holds the utmost importance due to its significance regarding early bone loss.Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like hig... Trabecular bone holds the utmost importance due to its significance regarding early bone loss.Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like high risk of fracture.The objective of this paper is to inspect the characteristics of the Trabecular Bone by using the Magnetic Resonance Imaging(MRI)technique.These characteristics prove to be quite helpful in studying different studies related to Trabecular bone such as osteoporosis.The things that were considered before the selection of the articles for the systematic review were language,research field,and electronic sources.Only those articles written in the English language were selected as it is the most prominent language used in scientific,engineering,computer science,and biomedical researches.This literature review was conducted on the articles published between 2006 and 2020.A total of 62 research papers out of 1050 papers were extracted which were according to our topic of review after screening abstract and article content for the title and abstract screening.The findings from those researches were compiled at the end of the result section.This systematic literature review presents a comprehensive report on scientific researches and studies that have been done in the medical area concerning trabecular bone. 展开更多
关键词 Magnetic resonance imaging high resolution trabecular bone(TB) bone structure machine learning
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Factors associated with trabecular bone score in postmenopausal women with type 2 diabetes and normal bone mineral density
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作者 Olga N Fazullina Anton I Korbut Vadim V Klimontov 《World Journal of Diabetes》 SCIE 2022年第7期553-565,共13页
BACKGROUND Osteoporosis and type 2 diabetes(T2D)have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare burden.In T2D,bone mineral density(BMD)may underestimate the risk... BACKGROUND Osteoporosis and type 2 diabetes(T2D)have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare burden.In T2D,bone mineral density(BMD)may underestimate the risk of low-energy fractures as bone quality is reduced.It was hypothesized that a decrease in the trabecular bone score(TBS),a parameter assessing bone microarchitecture,may be an early marker of impaired bone health in women with T2D.AIM To identify clinical and body composition parameters that affect TBS in postmenopausal women with T2D and normal BMD.METHODS A non-interventional cross-sectional comparative study was conducted.Potentially eligible subjects were screened at tertiary referral center.Postmenopausal women with T2D,aged 50-75 years,with no established risk factors for secondary osteoporosis,were included.BMD,TBS and body composition parameters were assessed by dual-energy X-ray absorptiometry.In women with normal BMD,a wide range of anthropometric,general and diabetes-related clinical and laboratory parameters were evaluated as risk factors for TBS decrease using univariate and multivariate regression analysis and analysis of receiver operating characteristic(ROC)curves.RESULTS Three hundred twelve women were initially screened,176 of them met the inclusion criteria and underwent dual X-ray absorptiometry.Those with reduced BMD were subsequently excluded;96 women with normal BMD were included in final analysis.Among them,43 women(44.8%)showed decreased TBS values(≤1.31).Women with TBS≤1.31 were taller and had a lower body mass index(BMI)when compared to those with normal TBS(Р=0.008 and P=0.007 respectively).No significant differences in HbA1c,renal function,calcium,phosphorus,alkaline phosphatase,PTH and 25(ОН)D levels were found.In a model of multivariate linear regression analysis,TBS was positively associated with gynoid fat mass,whereas the height and androgen fat mass were associated negatively(all P<0.001).In a multiple logistic regression,TBS≤1.31 was associated with lower gynoid fat mass(adjusted odd ratio[OR],0.9,95%confidence interval[CI],0.85-0.94,P<0.001),higher android fat mass(adjusted OR,1.13,95%CI,1.03-1.24,P=0.008)and height(adjusted OR,1.13,95%CI,1.05-1.20,P<0.001).In ROC-curve analysis,height≥162.5 cm(P=0.04),body mass index≤33.85 kg/m2(P=0.002),gynoid fat mass≤5.41 kg(P=0.03)and android/gynoid fat mass ratio≥1.145(P<0.001)were identified as the risk factors for TBS reduction.CONCLUSION In postmenopausal women with T2D and normal BMD,greater height and central adiposity are associated with impaired bone microarchitecture. 展开更多
关键词 DIABETES OSTEOPOROSIS bone mineral density trabecular bone score OBESITY Body composition
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Imaging Analysis of Trabecular Bone Texture Based on the Initial Slope of Variogram of Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jianfeng Chen Qifeng Ying 《Open Journal of Radiology》 2022年第3期78-85,共8页
Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data f... Background: When applied to trabecular bone X-ray images, a method for analyzing trabecular bone texture based on the initial slope of variogram (ISV) was used to assess the trabecular bone health. Methodology: Data from more than two hundred subjects were retrospectively studied. For each subject, a DXA (GE Lunar Prodigy) scan of the forearm was performed, and bone mineral density (BMD) value was measured at the location of ultra-distal radius, X-ray digital image of the same forearm was taken on the same day, and ISV value over the same location of ultra-distal radius was calculated. Pearson’s correlation coefficients were calculated to examine the correlation between BMD and ISV of the trabecular bones located at the same ultra-distal radius. ISV values changed with subjects’ age were also reported. Results: The results show that ISV value was highly correlated with the DXA-measured BMD of the same trabecular bone located at the ultra-distal radius. The correlation coefficient between ISV and BMD with the 95% confident was 0.79 ± 0.09. They also demonstrated that the age-related changes in trabecular bone health and differentiated age patterns in males and females, respectively. The results showed that the decrease in BMD was accompanied by a decrease in the initial slope of variogram (ISV). Conclusions: This study suggests that ISV might be used to quantitatively evaluate trabecular health for osteoporosis and bone disease diagnosis. 展开更多
关键词 trabecular bone Texture Digital X-Ray Image bone Mineral Density Ultra-Distal Radius Initial Slope of Variogram
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Micro-computed tomography assessment of human femoral trabecular bone for two disease groups(fragility fracture and coxarthrosis):Age and gender related effects on the microstructure
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作者 Ana Catarina Vale Manuel F.C.Pereira +7 位作者 Antonio Maurício Bruno Vidal Ana Rodrigues Joana Caetano-Lopes Ara Nazarian Joao E.Fonseca Helena Canhao Maria Fatima Vaz 《Journal of Biomedical Science and Engineering》 2013年第2期175-184,共10页
The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and ... The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and osteoarthritis was analyzed. A prior analysis of the effects of some procedure variables on the micro-CT results was performed. Preliminary micro-CT scans were performed with three voxel resolutions and two acquisition conditions. On the reconstruction step, the image segmentation was performed with three different threshold values. Samples were collected from patients, with coxarthrosis (osteoarthritis) or fragility fracture (osteoporosis). The specimens of the coxarthrosis group include twenty females and fifteen males, while the fragility fracture group was composed by twenty three females and seven males. The mean age of the population was 69 ± 11 (females) and 67 ± 10 years (males), in the coxarthrosis group, while in the fragility fracture group was 81 ± 6 (females) and 78 ± 6 (males) years. The 30 μm voxel size provided lower percentage difference for the microarchitecture parameters. Acquisition conditions with 160 μA and 60 kV permit the evaluation of all the volume’s sample, with low average values of the coefficients of variation of the microstructural parameters. No statistically significant differences were found between the two diseases groups, neither between genders. However, with aging, there is a decrease of bone volume fraction, trabecular number and fractal dimension, and an increase of structural model index and trabecular separation, for both disease groups and genders. The parameters bone specific surface, trabecular thickness and degree of anisotropy have different behaviors with age, depending on the type of disease. While in coxarthrosis patients, trabecular thickness increases with age, in the fragility fracture group, there is a decrease of trabecular thickness with increasing age. Our findings indicate that disease, age and gender do not provide significant differences in trabecular microstructure. With aging, some parameters exhibit different trends which are possibly related to different mechanisms for different diseases. 展开更多
关键词 trabecular bone Micro-Computed Tomography Coxarthrosis Fragility Fracture Age GENDER
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Fractal lacunarity of trabecular bone and magnetic resonance imaging:New perspectives for osteoporotic fracture risk assessment 被引量:3
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作者 Annamaria Zaia 《World Journal of Orthopedics》 2015年第2期221-235,共15页
Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern eve... Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density(BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture(TBA) during aging and osteoporosis. Magnetic resonance imaging(MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest fractal analysis as a promising approach to quantify morphofunctional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures. 展开更多
关键词 OSTEOPOROSIS Fracture risk trabecular bone MICROARCHITECTURE FRACTAL analysis FRACTAL LACUNARITY
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EFFECTS OF ALENDRONATE ON STRUCTURAL PROPERTIES OF TRABECULAR BONE IN DOGS
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作者 胡建华 张良 +1 位作者 赵立连 黄公怡 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第4期210-214,共5页
Objective. To evaluate the effects of alendronate on the structural properties of trabecular bone.Methods. Alendronate was administered at a daily p.o. Dose of 0. 5 mg/kg over a 12-week period in hound dogs (n = 8 for... Objective. To evaluate the effects of alendronate on the structural properties of trabecular bone.Methods. Alendronate was administered at a daily p.o. Dose of 0. 5 mg/kg over a 12-week period in hound dogs (n = 8 for both the control and treated group), and the structural indices of the lumbar vertebral (L1 and L2) trabecular bone were assessed directly from 3-D images.Results. Treatment with alendronate increased bone volume fraction by 9. 5% and 7.7% in L1 and L2 respectively. Trabecular thickness significantly increased after alendronate treatment, whereas trabecular separation remained constant. The degree of anisotropy for the alendronate- treated group was decreased compared with that of the control group. Bone surface to volume ratio declined significantly in the alendronate-reated group, whereas alendrenate induced a higher bone surface density.Conclusion. Alendronate increased the structural properties of canine trabecular bone after short-term treatment at a dose of 0. 5 mg @ kg-1@day-1. 展开更多
关键词 阿仑膦酸 骨小梁 结构特性 成骨作用
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Energy Based Simulation of Trabecular Bone Fracture Healing Using Finite Element and Fuzzy Logic
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作者 Mina Soleimanifar Hamid R. Katoozian 《Applied Mathematics》 2013年第5期49-55,共7页
The trabecular bone fracture healing differs from diaphyseal fracture healing, in which trabecular bone heals based on intramembraneous ossification. The process includes a small callus formation, then woven bone form... The trabecular bone fracture healing differs from diaphyseal fracture healing, in which trabecular bone heals based on intramembraneous ossification. The process includes a small callus formation, then woven bone forms, it follows by remodeling process to form regular trabecular bone. The objective of this study was to present an energy based model to simulate bone formation and remodeling during trabecular bone fracture healing. This modeling mainly focused on the mechanical factors. The model distinguishes three basic type of tissue: bone, cartilage and soft tissue. In order to determine tissue differentiation a fuzzy controller was proposed. An algorithm was developed to link the fuzzy logic controller to a finite element model (FEM) of trabecular bone. In general, finite element analysis provides input for fuzzy controller. Based on the input data, the fuzzy system selects the type of tissue to build. Strain energy density was used as the mechanical stimulus and a new parameter was incorporated in to the healing process as the remodeling index. 展开更多
关键词 Fracture HEALING trabecular bone Finite Element Fuzzy LOGIC
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Time Course of Changes in Trabecular Bone Microstructure in Rats with Spinal Cord Injury
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作者 Akira Minematsu Yasue Nishii +1 位作者 Hidetaka Imagita Susumu Sakata 《Journal of Life Sciences》 2014年第6期522-528,共7页
关键词 脊髓损伤 大鼠模型 骨小梁 时间进程 微结构 WISTAR大鼠 计算机断层成像 血清无机磷
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Evaluation of damage to trabecular bone of the osteoporotic human acetabulum at small strains using nonlinear micro-finite element analyses 被引量:3
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作者 DING Hai ZHU Zhen-an DAI Ke-rong 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第17期2041-2047,共7页
Background With advance of age, alterations in bone quality, quantity and microarchitecture render osteoporotic trabecular bone become more sensitive to local failure. The aims of the present study were to clarify the... Background With advance of age, alterations in bone quality, quantity and microarchitecture render osteoporotic trabecular bone become more sensitive to local failure. The aims of the present study were to clarify the extent to which the distribution of tissue-level stresses and strains was affected by structural changes and the extent to which osteoporotic acetabular trabecular bone was damaged at small strains. Methods Using a DAWING 4000A supercomputer, nonlinear micro-finite element (μFE) analyses were performed to calculate the tissue-level strains and stresses for each element in the trabecular bone of one osteoporotic acetabulum at small strains to quantify the tissue-level damage accumulation and mechanical properties. Results In contour plots of the tissue, maximum principal logarithmic strains, high tissue-level strains, both compressive and tensile, were observed in the osteoporotic trabecular bone at small apparent strains from 0.2% to 0.5% strain. The compressive apparent stress-strain curve showed typical nonlinear behavior and tangent modulus reduction with increasing strains. The microdamage curve suggested that microdamage began at 0.2% apparent strain in the osteoporotic trabecular bone and increased sharply, although very few microfractures occurred. The quartiles of the maximum principal logarithmic strains, minimum principal logarithmic strains and Von Mises stresses increased nonlinearly. For the inter-quartile range of the Von Mises stresses, a leap occurred at small strains ranging from 0.2% to 0.3% while microdamage commenced. Conclusions Extensive microdamage was primarily responsible for the large loss in apparent mechanical properties that occurred in the trabecular bone of the osteoporotic acetabulum at small strains. With increasing apparent strains, continuous nonlinear increments of tissue-level strains and stresses resulted in microdamage that propagated throughout the specimen with very few microfractures. Chin Med J 2009; 122(17):2041-204 7 展开更多
关键词 mechanical property trabecular bone nonlinear micro-finite element analysis ACETABULUM OSTEOPOROSIS
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Effect of trabecular bone material properties on ultrasonic backscattering signals 被引量:2
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作者 LIU Chengcheng TA De'an WANG Weiqi 《Chinese Journal of Acoustics》 2014年第1期73-82,共10页
In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain (FDTD) simulations, and the effect of trabecular material properties on these signals was analyzed.... In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain (FDTD) simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient (BSC) and integrated backscatter coefficient (IBC) were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density (BMD) and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status. 展开更多
关键词 bone Effect of trabecular bone material properties on ultrasonic backscattering signals BSC IBC FDTD
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Elastic modulus and hardness of cortical and trabecular bovine bone measured by nanoindentation 被引量:4
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作者 HODGSON P D 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期744-748,共5页
The elastic modulus and hardness of several microstructure components of dry bovine vertebrae and tibia have been investigated in the longitude and transverse directions using nanoindentation. The elastic modulus for ... The elastic modulus and hardness of several microstructure components of dry bovine vertebrae and tibia have been investigated in the longitude and transverse directions using nanoindentation. The elastic modulus for the osteons and the interstitial lamellae in the longitude direction were found to be (24.7±2.5) GPa and (30.1±2.4) GPa. As it's difficult to distinguish osteons from interstitial lamellae in the transverse direction, the average elastic modulus for cortical bovine bone in the transverse direction was (19.8±1.6) GPa. The elastic modulus for trabecular bone in the longitude and transverse direction were (20±2) GPa and (14.7±1.9) GPa respectively. The hardness also varied among the microstructure components in the range of 0.41-0.89 GPa. Analyses of variance show that the values are significantly different. 展开更多
关键词 牛骨 弹性模量 硬度 骨皮质 骨小梁 纳米压痕法 测量 生物力学
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Research on Damage in Trabecular Bone of the Healthy Human Acetabulum at Small Strains Using Nonlinear Micro-finite Element Analysis 被引量:2
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作者 丁海 朱振安 +2 位作者 戴克戎 叶铭 王承焘 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第5期623-628,共6页
The mechanical properties of the pelvic trabecular bone have been studied at the continuum level. However, nothing is known about the tissue-level damage in the trabecular bone of the healthy human acetabulum at appar... The mechanical properties of the pelvic trabecular bone have been studied at the continuum level. However, nothing is known about the tissue-level damage in the trabecular bone of the healthy human acetabulum at apparent small strains characteristic of habitual. By a DAWING 4000 A supercomputer, nonlinear micro-finite element (μFE) analysis was performed to quantify tissue-level damage accumulation in trabecular bone at small strains. The data indicate that damage in trabecular bone commence at 0.2% apparent strain. The findings imply that tissue yielding can initiate at very low strains in the trabecular bone of the healthy acetabulum and that this local failure has negative consequences on the apparent mechanical properties of trabecular bone. 展开更多
关键词 机械力学 X线检查 小梁骨 健康状态
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Estimating mean trabecular bone spacing based on the combination of Hilbert transform and fundamental frequency estimation
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作者 李颖 徐峰 +3 位作者 刘成成 许凯亮 他得安 王威琪 《Science Foundation in China》 CAS 2017年第3期57-71,共15页
Ultrasonic backscatter signals from cancellous bone are sensitive to the microstructure of trabecular bone,and thus enable the feasibility to extract microstructural information of trabecular bone.The mean trabecular ... Ultrasonic backscatter signals from cancellous bone are sensitive to the microstructure of trabecular bone,and thus enable the feasibility to extract microstructural information of trabecular bone.The mean trabecular bone spacing(MTBS)is an important parameter for characterizing bone microstructure.This paper proposes an MTBS estimation method based on the combination of Hilbert transform and fundamental frequency estimation(CHF). The CHF was verified with ultrasonic backscatter signals from simulations and in vitro measurements at a central frequency of 5MHz.The CHF method was compared with the simplified inverse filter tracking(SIFT)method,Simons' Quadratic Transformation(QT)method,Singular Spectrum Analysis(SSA)method,and Spectral Autocorrelation(SAC)method.Monte-Carlo simulations were performed by varying the MTBS,signal-to-noise ratio(SNR),standard deviation of regular spacing(SDRS),amplitude ratio of diffuse scattering to regular scattering(Ad)and frequency dependent attenuation(nBUA).The simulation results showed that the CHF method had a better performance in MTBS estimation under almost all the examination conditions except for SNR.The estimation percentage correct(EPC)was greater than 90% when the MTBS was in the range of 0.4to 1.4mm.In the in vitro measurements,the estimated EPC by the CHF method was91.25±7.81%(mean±standard deviation).A significant correlation was observed for the CHF-estimated MTBS and micro-computed tomography(μ-CT)-measured values(R^2=0.75,p<0.01).These results demonstrate that the CHF method is anti-interference for MTBS estimation and can be used to estimate trabecular bone spacing. 展开更多
关键词 超声的反散射 意味着 trabecular 骨头间距评价 Hilbert 变换和基本频率评价 Cancellous 骨头微观结构
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Understanding Osteoporosis: Pathophysiology, Risk Factors, Diagnosis, and Management
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作者 Mahmoud Ismail 《Advances in Aging Research》 CAS 2024年第3期25-40,共16页
Osteoporosis is a systemic skeletal disease characterized by low bone mineral density (BMD) and deterioration of bone architecture, resulting in reduced bone strength and, consequently, increased susceptibility to fra... Osteoporosis is a systemic skeletal disease characterized by low bone mineral density (BMD) and deterioration of bone architecture, resulting in reduced bone strength and, consequently, increased susceptibility to fractures which poses a significant public health concern worldwide, particularly in aging populations [1]. The health-economic impact of vertebral and hip fractures has been extensively explored and it is well known that these fractures are associated with morbidity/disability and increased mortality;they also account for a substantial portion of the direct fracture costs. This review aims to provide a comprehensive overview of osteoporosis, including its pathophysiology, risk factors, diagnostic approaches, and management strategies. By elucidating the multifaceted nature of this condition, healthcare providers can better identify individuals at risk, implement preventive measures, and optimize treatment to reduce the burden of osteoporotic fractures. 展开更多
关键词 OSTEOPOROSIS bone Mineral Density Fractures Risk Factors DIAGNOSIS MANAGEMENT FRAX (Fracture Risk Assessment Tool) trabecular bone Score (TBS)
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骨小梁髋假体柄植入的应力分析
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作者 李博 高丽兰 +5 位作者 陈亚 刘淑红 胡亚辉 吕林蔚 叶金铎 张春秋 《医疗卫生装备》 CAS 2024年第3期29-35,共7页
目的:分析髋关节置换中实心钛合金假体与骨小梁假体柄植入的应力。方法:基于Mimics软件逆向建立股骨模型,并使用Geomagic软件对股骨模型进行优化,再通过SolidWorks软件将模型实体化。将截骨后的股骨与金属股骨柄进行装配,并将装配好的... 目的:分析髋关节置换中实心钛合金假体与骨小梁假体柄植入的应力。方法:基于Mimics软件逆向建立股骨模型,并使用Geomagic软件对股骨模型进行优化,再通过SolidWorks软件将模型实体化。将截骨后的股骨与金属股骨柄进行装配,并将装配好的模型导入ABAQUS中进行有限元计算。将股骨上部分为内侧近端点(小转子区)、外侧近端(大转子区)、股骨干近端点(茎突中段周围)、远端区域(茎突末端周围和远端)4个区域(处于不同整合状态),计算步态、爬楼梯载荷下植入实心钛合金假体和骨小梁假体前后的股骨应力以及区域未整合时的界面应力,并通过应力椭球分析骨界面的变形类型。结果:在小转子区,步态和爬楼梯载荷下骨小梁假体相比实心钛合金假体应力屏蔽率分别降低了20.5%和14.7%。实心钛合金假体存在不同整合状态时,步态与爬楼梯载荷下界面拉应力最大分别为10.842、12.900 MPa,剪应力最大分别为7.050、6.805 MPa;而骨小梁假体存在不同整合状态时,步态与爬楼梯载荷下界面拉应力最大分别为3.858、4.389 MPa,剪应力最大分别为4.156、3.854 MPa。2种不同载荷下,界面内侧剪应力椭球开口朝向两侧,骨界面发生拉伸变形;界面外侧剪应力椭球上下开口,发生压缩变形。结论:全髋关节置换术后,骨小梁假体的整体性能优于实心钛合金假体,且假体-骨界面未整合边缘易发生应力集中以及变形,引发进一步失效。 展开更多
关键词 髋关节置换 骨小梁型假体 假体柄 应力屏蔽 界面强度 界面变形
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