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1.
背景:关节软骨一旦出现裂纹缺损其力学性能会发生改变,而先前研究中针对受损关节软骨的探究多集中在压缩,对于拉伸性能的研究较少。目的:预先在软骨层试样上制造裂纹缺损,测试其单轴准静态拉伸性能。方法:选取新鲜成年猪膝关节的关节软骨,制备含裂纹缺损的软骨试样,在不同应力率下(0.001,0.01,和0.1 MPa/s)测试其拉伸性能,在不同恒定应力下(1,2,3 MPa)测试其蠕变性能。结果与结论:①不同应力速率下的拉伸实验中,随着应力速率的增加,达到相同应变所需的应力逐渐增大,且试件的杨氏模量随应力率的增加而增加;②不同应力速率下含裂纹缺损关节软骨的拉伸应力-应变曲线不重合,说明含裂纹缺损关节软骨的拉伸性能具有率相关性;③不同恒定拉应力水平下的蠕变实验中,蠕变应变随着拉应力水平的提高而增大,蠕变柔量随拉应力水平的提高而降低,并且随着蠕变时间的推移蠕变应变先快速增加后缓慢增加;④结果表明,不同应力率和不同恒定应力对含裂纹缺损关节软骨的拉伸力学性能影响较大,该实验结果可为缺损关节软骨的修复提供力学参考。 相似文献
2.
The aim of this study was to visualize, at the ultrastructural level, the deformation and failure mechanism of cartilage matrix in the tensile mode. Full-thickness dumbbell-shaped specimens were prepared from adult bovines. There were two specimen groups; in the 'parallel' group the specimen axis was parallel to the split lines defining the preferential orientation of the collagen in the articular surface, and in the 'perpendicular' group the specimen axis was perpendicular to the split lines. Specimens were placed with the articular surface uppermost and subjected to a graded series of strain within individual mini-tension devices, while observed with stereomicroscopy and confocal laser scanning microscopy. Thereafter, the changes in the ultrastructure were observed with both scanning and transmission electron microscopy. The mechanism of cartilage failure in the tensile mode comprised the following stages, whether the strain was applied parallel or perpendicular to the split line. (1) At 0% strain a fibrillar meshwork within the articular surface was predominantly orientated in the direction of the split line. (2) As strain increased, the fibrillar meshwork became more orientated in the parallel group and reorientated in the perpendicular group in the direction of the applied strain. (3) After complete reorientation of the fibrillar meshwork in the direction of the applied strain, the initial sign of failure was rupture of the fibrillar meshwork within the articular surface. (4) Subsequently, the rupture rapidly propagated into the deeper layers. Greater strains were required for fibrillar reorientation and complete rupture in the 'perpendicular group' than in the parallel group. 相似文献
3.
目的探讨炎症因子白介素-1β(interleukin-1β, IL-1β)对软骨表层细胞(articular cartilage superficial zone cells,ACSCs)衰老的调控作用和相关机制。方法用纤连蛋白黏附法分离培养ACSCs,根据实验分为对照组和IL-1β处理组,采用MTT检测细胞增殖情况,衰老相关-β-半乳糖苷酶(SA-β-gal)染色检测SA-β-gal阳性细胞数,Western blot检测p21和p53蛋白水平,实时荧光定量PCR(RT-qPCR)检测衰老相关分泌表型(senescence-associated secretory phenotype, SASP)因子il-6、Mmp-3和Mmp-13 m RNA水平,CellROX试剂检测活性氧(reactive oxygen species, ROS)水平,JC-1试剂检测线粒体膜电位。最后,取ACSCs设IL-1β处理组和IL-1β+N-乙酰半胱氨酸(N-acetylcysteine, NAC)处理组,检测NAC处理后对IL-1β引起的细胞ROS水平、细胞增殖、SA-β-gal阳性细胞数、p21... 相似文献
4.
Communication between paired chondrocytes in the superficial zone of articular cartilage 总被引:2,自引:0,他引:2
The regeneration and repair of cartilage damaged by injury or disease, a major goal of orthopaedic science, depends on understanding the structure and function of both the extracellular matrix and the chondrocytes. In this study, we explored the in situ organization and potential interactions between chondrocytes in the superficial zone of adult rabbit articular cartilage. Some chondrocytes in this zone were observed close together and appeared to be paired whereas others were solitary. The shared surfaces of a chondrocyte pair were separated by a narrow plate of extracellular matrix, into which extended small cytoplasmic projections from both cells. Furthermore, the spatial distribution of major cellular landmarks, such as the nucleus and centrosome as well as some intracellular proteins such as connexin-43, tended to be mirrored about this matrix plate. Fluorescence recovery after photobleaching revealed the fluorescent dye calcein-AM dye can pass between paired cells, and that the passage of this dye can be inhibited by the gap junction blocker octanol. These results illustrate that rapid cellular communication is possible between cells in the superficial layer of adult articular cartilage, which challenges the current thinking that these chondrocytes function in isolation. 相似文献
5.
目的使用修饰后的原子力显微镜(atomic force microscopy,AFM)探针研究关节软骨的微摩擦接触力学性能。方法使用微操作器对AFM氮化硅探针进行修饰处理,具体操作为在探针上粘贴玻璃微球作为针尖,然后使用修饰后的探针研究人体和牛关节软骨的微摩擦接触力学性能。结果人体和牛软骨的粗糙度分别为(68.63±6.22)、(50.16±6.47)nm,随着载荷的增大,人体和牛软骨的摩擦力逐渐增大。当探针滑动速度从0增加到100μm/s时,试样与探针之间的摩擦力增速很快;当速度从100μm/s增加到300μm/s时,摩擦力上升缓慢。结论软骨表面具有明显的纤维状结构,软骨的粗糙度与测量范围直接相关。随着速度或载荷的增大,人体和牛软骨的摩擦力增大,变化范围相同。探讨关节软骨在微摩擦试验中的力学和摩擦学性能表现,对于认识软骨损伤机制和医用人工关节抗磨材料的开发具有重要意义。 相似文献
6.
Diogo Correa Maldonado Marcelo Cavenaghi Pereira da Silva Semaan El‐Razi Neto Mônica Rodrigues de Souza Romeu Rodrigues de Souza 《Journal of anatomy》2013,222(5):518-525
Studies have determined the effects of joint immobilization on the articular cartilage of sedentary animals, but we are not aware of any studies reporting the effects of joint immobilization in previously trained animals. The objective of the present study was to determine whether exercise could prevent degeneration of the articular cartilage that accompanies joint immobilization. We used light microscopy to study the thickness, cell density, nuclear size, and collagen density of articular cartilage of the femoral condyle of Wistar rats subjected to aerobic physical activity on an adapted treadmill five times per week. Four groups of Wistar rats were used: a control group (C), an immobilized group (I), an exercised group (E), and an exercised and then immobilized group (EI). The right knee joints from rats in groups I and EI were immobilized at 90 °C of flexion using a plastic cast for 8 weeks. Cartilage thickness decreased significantly in group I (mean, 120.14 ± 15.6 μm, P < 0.05), but not in group EI (mean, 174 ± 2.25), and increased significantly in group E (mean, 289.49 ± 9.15) compared with group C (mean, 239.20 ± 6.25). The same results were obtained for cell density, nuclear size, and collagen density (in all cases, P < 0.05). We concluded that exercise can prevent degenerative changes in femoral articular cartilage caused by immobilization of the knee joint. 相似文献
7.
Postnatal development of the collagen matrix in rabbit tibial plateau articular cartilage 总被引:1,自引:0,他引:1
Changes in the 3-dimensional arrangement of the articular cartilage matrix during growth of the rabbit tibial plateau were studied. Knees from newborn, and 1, 2 and 6 wk-old rabbits were compared with those of adults by light and electron microscopy. The specimens were fixed, embedded en bloc in epoxy resin and sectioned vertically/coronally through the point where the articular cartilage was thickest in the adult medial tibial plateau. At birth, the proximal tibial epiphysis was cartilaginous, but nascent articular cartilage was recognisable as a densely cellular layer covering the tibial condyle. Within 30 μm of the articular surface, the chondrocytes were flattened and collagen fibres ran among these cells in a direction parallel to the surface. Deeper in the articular cartilage, rounded cells were evenly distributed within a random collagen fibril network. At the centre of the plateau, the tangential layer changed little during growth, whereas the subjacent cellular layer grew in thickness and steadily achieved a more vertical character in the organisation of its constituent collagen and cellular elements. At 1 wk, cells were separated into clusters by acellular regions filled with collagen fibrils. At 2 wk, cells within the forming radial zone were aligned in columns bracketed by vertical collagen fibres. Continuity of these vertical fibres with those in the tangential surface layer was evident at this age. The chondrocytes were surrounded by fibrous capsules typical of chondrons. By 6 wk, the bases of the radial collagen fibres in the very centre of the condyle had calcified, as had the adjacent hypertrophic hyaline cartilage. A solid subchondral plate and tidemark did not appear until skeletal maturity. From birth to age 6 wk, maximum thickness of the layer identified as primordial articular cartilage increased from 0.13 mm to 0.70 mm, and was 1.5 mm in the adult. Throughout growth, however, the thickness of the tangential layer in the centre of the plateau never exceeded 0.05 μm. In the patella, femoral head and peripheral tibial plateau, cartilage development followed the same general sequence. In contrast to the central tibial plateau, the tangential layer also grew in thickness, but at a slower rate than that of the radial zone. At all ages, the developing articular cartilage was structurally distinct from the deeper hyaline cartilage which contributed to growth of the ossification centre through enchondral ossification. The collagen matrix of articular cartilage acquires a characteristic, orderly 3-dimensional structure soon after birth. Growth in cartilage thickness occurs primarily through enlargement of the radial zone. 相似文献
8.
Hyeon Lee W. Grant Kirkland Ryan N. Whitmore Kelcie M. Theis Hannah E. Young Ashton J. Richardson 《Connective tissue research》2014,55(5-6):339-347
Purpose: Thicknesses of fresh equine articular cartilage surfaces from the fetlock, carpal and stifle joints were measured employing a needle probe test.Materials and methods: Eighty-seven samples used in measurement were cultivated from fetlock, carpal and stifle joints of 12 deceased within 4?h of death. After approximately three minutes of exposure to air during dissection, all cartilage samples were preserved in a saline solution to keep the articular cartilage hydrated for testing. The thickness was measured on five different spots on the same sample. The thicknesses of the fetlock, carpus and stifle were compared.Results: The articular cartilage of the stifle was thicker than the fetlock and carpus, while the fetlock and the carpus had similar thickness values. The average thickness of the fetlock, carpal and stifle joint are 0.86, 0.87 and 2.1?mm, respectively. They were statistically compared using the Student t-test. The differences on the articular cartilage thicknesses between the fetlock and stifle, and carpus and stifle were “very highly significant” (p?0.001). This indicates that the articular cartilage thickness of the stifle is significantly different from that of the fetlock and carpus. Four different surfaces in the fetlock and four in the carpal joint were also compared. Significant differences between each set of the four surfaces were not observed. In the carpus, the difference in thickness between the distal radius and proximal third carpal bone articular cartilage surfaces as well as the proximal radial carpal bone and distal radial carpal bone articular cartilage surfaces were statistically significant. 相似文献
9.
目的 比较人膝关节软骨和聚乙烯醇水凝胶(PVA-H)人工软骨的生物力学性能 方法 使用人膝关节软骨和PVA-H人工软骨进行轴向压缩试验,分别进行压缩应力应变、应力松弛和蠕变实验,得到关节软骨和PVA-H人工软骨的应力应变关系。结果 实验中人关节软骨和PVA-H的力学性能有差异,人关节软骨压缩模量大于PVA-H人工软骨,人关节软骨的压缩模量为(3.6492±0.6199)Mpa,PVA-H的压缩模量为(1.5951±0.1469)Mpa。结论 软骨和PVA-H人工软骨的生物力学性能具有一定差异,试验结果对人工软骨的进一步改进具有指导意义。 相似文献
10.
Reinout Stoop Peter M. van der Kraan Pieter Buma Anthony P. Hollander A. Robin Poole Wim B. van den Berg 《The Journal of pathology》1999,188(3):329-337
Degradation of type II collagen is thought to be a key step in the destruction of articular cartilage in patients with rheumatoid arthritis or osteoarthritis. The aim of this study was to investigate whether type II collagen degradation is associated with cartilage destruction. Type II collagen degradation was studied in two murine arthritis models, zymosan-induced arthritis (ZIA), which develops reversible articular cartilage damage based on proteoglycan analysis, and antigen-induced arthritis (AIA), in which there is irreversible damage to the cartilage. Type II collagen degradation was assayed immunohistochemically using the COL2-3/4m antibody which recognizes denatured type II collagen, such as is produced by collagenase cleavage. In both models, degradation of type II collagen was observed in the non-calcified articular cartilage of arthritic but not of control knees. In the patella-femoral compartment, collagen denaturation started to increase on day 3 (ZIA) and day 7 (AIA) and remained high on day 14. In contrast, in the tibia-femoral compartment, type II collagen breakdown was not increased before 14 days in either model. By 28 days, collagen denaturation was strongly reduced in the patella-femoral compartment in the ZIA model, but persisted in the tibia-femoral compartment in both models. In conclusion, increased type II collagen degradation was found in articular cartilage of both ZIA and AIA animals. Since ZIA does not develop irreversible cartilage destruction, this indicates that cartilage may have the ability to withstand a limited degree of type II collagen degradation without developing irreversible damage. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
11.
Role of uppermost superficial surface layer of articular cartilage in the lubrication mechanism of joints 总被引:6,自引:0,他引:6
P. KUMAR M. OKA J. TOGUCHIDA M. KOBAYASHI E. UCHIDA T. NAKAMURA K. TANAKA 《Journal of anatomy》2001,199(3):241-250
The uppermost superficial surface layer of articular cartilage, the 'lamina splendens' which provides a very low friction lubrication surface in articular joints, was investigated using atomic force microscopy (AFM). Complementary specimens were also observed under SEM at −10 °C without dehydration or sputter ion coating. Fresh adult pig osteochondral specimens were prepared from the patellas of pig knee joints and digested with the enzymes, hyaluronidase, chondroitinase ABC and alkaline protease. Friction coefficients between a pyrex glass plate and the osteochondral specimens digested by enzymes as well as natural (undigested) specimens were measured, using a thrust collar apparatus. Normal saline, hyaluronic acid (HA) and a mixture of albumin, globulin, HA (AGH) were used as lubrication media. The surface irregularities usually observed in SEM studies were not apparent under AFM. The articular cartilage surface was resistant to hyaluronidase and also to chondroitinase ABC, but a fibrous structure was exhibited in alkaline protease enzymes-digested specimens. AFM analysis revealed that the thickness of the uppermost superficial surface layer of articular cartilage was between 800 nm and 2 μm in adult pig articular cartilage. The coefficient of friction (c.f.) was significantly higher in chondroitinase ABC and alkaline protease enzymes digested specimens. Generally, in normal saline lubrication medium, c.f. was higher in comparison to HA and AGH lubrication media. The role of the uppermost, superficial surface layer of articular cartilage in the lubrication mechanism of joints is discussed. 相似文献
12.
The mechanical behavior of bovine articular cartilage in shear was measured and related to its structure through the depth of the tissue. To make these measurements, we designed an apparatus that could apply controlled shear displacement and measure the resulting shear force on cartilage specimens. Shear displacement and shear strain were obtained from confocal images of photobleached lines on fluorescently stained deformed samples. Depth-dependent collagen structure was obtained using compensated polarized light microscopy. Depth-dependent shear behavior and structure of samples from two animals were measured (group A and B). Both animals were 18–24 months old, which is the range in which they are expected reach skeletal maturity. In mature samples (group A), the stiffest region was located beneath the superficial zone, and the most compliant region was found in the radial zone. In contrast, in samples that were in the process of maturing (group B) the most compliant region was located in the superficial zone. Compensated polarized light microscopy suggested that the animal from which the group A samples were obtained was skeletally mature, whereas the animal yielding the group B samples was in the process of maturing. Compensated polarized light microscopy was an important adjunct to the mechanical shear behavior in that it provided a means to reconcile differences in observed shear behavior in mature and immature cartilage. Although samples were harvested from two animals, there were clear differences in structure and shear mechanical behavior. Differences in the depth-dependent shear strain were consistent with previous studies on mature and immature samples and, based on the structural variation between mature and immature articular cartilage, their mechanical behavior differences can be tenable. These results suggest that age, as well as species and anatomic location, need to be considered when reporting mechanical behavior results. 相似文献
13.
A persistent hurdle in the field of tissue regeneration is to produce tissues with biochemical and biomechanical properties robust enough to meet the aggressive physiological demands of the native milieu. In an effort to improve these properties tissues grown in vitro are often subjected to mechanical stimuli that aim to recapitulate the in vivo physiology. These mechanical stimuli are thought to produce downstream alterations in intracellular ion concentrations, which ultimately give rise to increased biosynthesis. There is mounting evidence that these perturbations in the cellular microenvironment are regulated by the Ca2+-permeable transient receptor potential vanilloid 4 (TRPV4) channel. In this study we examined the effects of targeted TRPV4 activation on self-assembled articular cartilage constructs. The objectives of this study were: (i) to determine whether TRPV4 activation would enhance self-assembled constructs; (ii) to identify an optimal treatment time window for TRPV4 activation; and (iii) to compare TRPV4 activation which Na+/K+ pump inhibition, which has previously been shown to improve the construct tensile properties. This study employed a two phase approach. In Phase I self-assembled constructs were grown for 4 weeks and subjected to treatment with the TRPV4 agonist 4α-phorbol-12,13-didecanoate (4α-PDD) during three treatment time windows: t = 6–10, t = 10–14, and t = 14–18 days. Treatment for t = 10–14 days produced an 88% increase in collagen and a 153% increase in tensile stiffness. This treatment window was carried forward to Phase II. In Phase II we performed a head to head comparison between TRPV4 activation using 4α-PDD and Na+/K+ pump inhibition using ouabain. Treatment with 4α-PDD produced improvements on a par with ouabain (91–107% increases in tensile stiffness). The results of this study demonstrate the effectiveness of ion channel modulation as a strategy for improving engineered tissues. To our knowledge this is the first study to examine TRPV4 channel activation in tissue engineering. 相似文献
14.
Petro Julkunen Esa P. Halmesmäki Jarkko Iivarinen Lassi Rieppo Tommi Närhi Juho Marjanen Jarno Rieppo Jari Arokoski Pieter A. Brama Jukka S. Jurvelin Heikki J. Helminen 《Journal of anatomy》2010,217(3):262-274
Articular cartilage composition and structure are maintained and remodeled by chondrocytes under the influence of loading. Exercise‐induced changes in the composition, structure, mechanical properties and tissue integrity of growing and aging hamster articular cartilage were investigated. Articular cartilage samples (n = 191) were harvested from the proximal tibiae of hamsters aged 1, 3, 6, 12 and 15 months. The hamsters were divided into runners and controls. The runners had free access to a running wheel between 1 and 3 months (runner groups 3‐, 12‐ and 15‐month‐old hamsters) or 1 and 6 months (runner group 6‐month‐old hamsters) of age. Control animals were subjected to a sedentary lifestyle. Mechanical indentation tests and depth‐wise compositional and structural analyses were performed for the cartilage samples. Furthermore, the integrity of articular cartilage was assessed using histological osteoarthritis grading. Exercise affected the collagen network organization after a 5‐month exercise period, especially in the middle and deep zones. However, no effect on the mechanical properties was detected after exercise. Before the age of 12 months, the runners showed less osteoarthritis than the controls, whereas at 15 months of age the situation was reversed. It is concluded that, in hamsters, physical exercise at a young age enhances cartilage maturation and alters the depth‐wise cartilage structure and composition. This may be considered beneficial. However, exercise at a young age demonstrated adverse effects on cartilage at a later age with a significant increase in the incidence of osteoarthritis. 相似文献
15.
Yasuyuki Sasano Mitsuru Furusawa Haruo Ohtani Itaru Mizoguchi Ichiro Takahashi Manabu Kagayama 《Anatomy and embryology》1996,194(3):247-252
The present study was designed to investigate whether or not chondrocytes in articular cartilage express type I collagen in vivo under physiological conditions. Expressions of the gene and the phenotype of type I collagen were examined in rat tibial articular cartilage in the knee joint during development. Knee joints of Wistar rats at 1, 5, and 11 weeks postnatal were fixed in 4% paraformaldehyde with or without 0.5% glutaraldehyde and decalcified in 10% EDTA. After the specimens were embedded in paraffin and serial sections made, adjacent sections were processed for immunohistochemistry and in situ hybridization for type I collagen. The epiphysis of the tibia was composed of cartilage in week-1 rats. Formation of articular cartilage was in progress in week 5 as endochondral ossification proceeded and was completed in week 11. Anti-type I collagen antibody stained only the superficial area of the epiphysis in week 1, but the immunoreactivity was expanded into the deeper region of the articular cartilage with development in weeks 5 and 11. Hybridization signals for pro-alpha 1 (I) collagen were seen in some of chondrocytes in the epiphysis of the week-1 tibia. The most intense signals were identified in chondrocytes in week 5 and the signals appeared weaker in week 11. The present study demonstrated that chondrocytes synthesize type I collagen and accumulate the protein in the matrix during development of the articular cartilage. 相似文献
16.
背景:研究报道,联合使用姜提取物降低血清促炎细胞因子白细胞介素1β、白细胞介素6、肿瘤坏死因子α等水平与膝骨关节炎中软骨损伤的减轻有关。目的:观察红姜提取物灌胃对早期膝骨关节炎大鼠关节软骨保护情况及血清白细胞介素1β、白细胞介素6、肿瘤坏死因子α和软骨Col2α1 mRNA水平表达的影响,探讨红姜提取物对早期膝骨关节炎大鼠关节软骨保护作用及可能机制。方法:将50只SPF级SD大鼠随机分为空白组、模型组、红姜低剂量组、红姜高剂量组、阳性对照组,每组各10只。除空白组外,其余40只大鼠膝关节腔注射4%木瓜蛋白酶0.2 mL+0.03 mol/L的L-半胱氨酸混合溶液,建造膝骨关节炎模型。空白组与模型组常规饲养;红姜低剂量组、红姜高剂量组、阳性对照组分别予50 mg/kg的红姜提取物水溶液、100 mg/kg红姜提取物水溶液、18 mg/kg的塞来昔布胶囊水溶液灌胃,所有干预每日1次,共持续4周。治疗4周后取大鼠膝关节软骨进行番红O-固绿染色,并对关节软骨行Mankin评分,检测血清中白细胞介素1β、白细胞介素6、肿瘤坏死因子α及软骨中Col2α1 mRNA表达水平。实验方案经广州中医药大学动物实验伦理委员会批准,批准号:20190917002。结果与结论:①膝关节软骨的病理切片显示,模型组及各治疗组均有软骨基质流失,各治疗组Mankin评分均比空白组评分高(P<0.05),比模型组评分低(P<0.05),其中红姜高剂量组与阳性对照组评分差异无显著性意义(P>0.05),均显著低于红姜低剂量组(P<0.05);②血清白细胞介素1β、白细胞介素6、肿瘤坏死因子α结果显示,阳性对照组、红姜高剂量组、红姜低剂量组均比空白组表达上调(P<0.05),均比模型组表达下调(P<0.05),且各治疗组间水平阳性对照组<红姜高剂量组<红姜低剂量组(P<0.05);③软骨中Col2α1 mRNA结果显示,空白组与红姜高剂量组、阳性对照组的Col2α1 mRNA表达差异无显著性意义(P>0.05),模型组和红姜低剂量组Col2α1 mRNA表达相较其他3组均显著上调(P<0.05);④结果说明,红姜提取物可能主要通过抑制白细胞介素1β、白细胞介素6、肿瘤坏死因子α等炎症因子的表达,达到了保护膝骨关节炎关节软骨作用,从而延缓膝骨关节炎的发展进程;且相对于低剂量组,红姜提取物高剂量组的抗炎效果更好。 相似文献
17.
目的 采用不同加载速率对关节软骨进行非围限压缩试验,探究其不同层区的率相关性能。方法 采用新鲜猪关节软骨作为研究对象,结合非接触式数字图像相关技术,测试不同加载率下软骨不同层区的力学性能。结果 在恒定加载率作用下,取相同压缩应力时,软骨浅表层的压缩应变最大,深层区压缩应变最小,中间层压缩应变鉴于表层与深层之间;沿软骨厚度方向,从浅表层到深层,软骨的泊松比逐渐增大;不同加载率作用下,软骨的压缩应力 应变曲线不重合,说明关节软骨的压缩力学性能具有率相关性;随着加载速率的增大,软骨的弹性模量呈增大的趋势;取相同压缩应力时,加载率越大,不同层区的压缩应变都减小。结论 关节软骨沿厚度方向,从浅表层到深层的压缩应变逐渐减小,泊松比逐渐增大,软骨不同层区的力学性能具有率相关性。实验研究可为临床软骨疾病预防、治疗提供理论依据,同时对人工软骨力学评价具有重要意义。 相似文献
18.
背景:关节镜下微骨折治疗与骨软骨移植是关节软骨缺损主要的治疗方法之一,具有广阔的应用前景。
目的:探讨关节镜下微骨折治疗与自体和同种异体骨软骨移植治疗膝骨关节炎合并关节软骨缺损的效果。
方法:应用关节镜下微骨折治疗清理术结合软骨缺损区微骨折术治疗膝骨关节炎的临床疗效、临床症状及Tegner运动评级判定疗效并随访观察3-24个月。自体骨软骨移植治疗关节软骨缺损的患者进行观察随访,通过评价移植后关节活动度、临床症状的改善、关节影像学检查等评估自体骨软骨移植治疗的效果。并对同种异体骨软骨移植治疗关节软骨缺损进行动物实验研究,通过对移植部位的大体观察、组织学观察以及免疫组织化学染色观察,评估同种异体骨软骨移植治疗的效果。
结果与结论:关节软骨缺损应用关节镜下微骨折治疗后的患者,关节清理术结合软骨缺损区微骨折术总有效率89.7%。关节软骨缺损应用自体骨软骨移植治疗后的患者,关节疼痛、肿胀的症状改善,关节活动度正常,偶有关节静息痛或活动后轻微疼痛,影像学检查见移植骨软骨位置良好,修复愈合良好。关节软骨缺损应用同种异体骨软骨移植治疗后的实验动物,关节活动度正常,移植关节面光整,关节软骨被透明软骨覆盖,细胞有序排列,软骨基质分泌,修复软骨Ⅱ型胶原免疫组织化学染色强阳性。 相似文献
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目的通过比较膝关节骨性关节炎(OA)病人定量动态负荷前后膝关节软骨T2时间变化情况,分析MRIT2mapping序列反映软骨基质生物力学变化的灵敏度.并验证高磁场条件下人体关节负荷装置的有效性。方法10例膝关节OA病人,其中男性3例.女性7例:年龄4l~66岁.平均年龄57-3岁。依托人体下肢关节力学负荷装置,对其施加膝关节动态负荷。负荷前后行膝关节MRIT2maDping成像,将膝关节轴向负荷区软骨分为4个部位:胫骨平台内、外侧软骨区及股骨内、外侧髁软骨区.分别测量各部位软骨负荷前后的T,时间。对负荷前膝关节内、外侧软骨分级评估进行卡方检验,对同一软骨区动态负荷前后的T2时间进行配对t检验。结果负荷前膝关节内外侧软骨分级差异无统计学意义(P〉0.05)。OA病人负荷前后T2值,胫骨平台内侧软骨区分别为(39.59±4.17)ms、(40.14±4.49)ms(f=0.426,P=0.680);胫骨平台外侧软骨区(38.85±6.72)ms、(41.25±6.54)ms(t=1.704,P=0.123):股骨内侧髁软骨区(36.44±5.72)ms、(40.63±4.90)ms(t=1.783,P=0.108);股骨外侧髁软骨区(39.30±5.78)ms、(46.14±5.03)ms(t=2.826,P=0.020)。结论OA病人负荷后膝关节局部区域软骨区T2时间延长.自行设计的动态加压装置适合在高磁场条件下完成加压及MRI检查,有一定推广意义。 相似文献
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关节软骨损伤修复研究进展 总被引:3,自引:0,他引:3
徐敬 《国际病理科学与临床杂志》2015,35(3):455-461
各种原因导致的关节软骨损伤在临床十分常见,关节软骨缺乏血供,一旦受损,其自愈能力十分有限,甚至遗留永久性病变.所以关节软骨损伤的修复一直是国内外研究的热点问题.近年来随着生物学、力学、材料学等多学科的交叉发展,在关节软骨损伤修复方面又有了诸多发现.本文就目前各种关节软骨损伤修复方法,包括新兴的组织工程软骨与基因治疗技术的研究进展作一综述. 相似文献