骨质疏松动物模型骨的拉伸、压缩、扭转实验研究

研究了正常大鼠和去势所致大鼠骨质疏松以电针、灸法、电针加雌激素、灸法加雌激素治疗组大鼠骨的拉伸、压缩、扭转力学性质。选用36只280～320g，4～5月龄Wistar雌性大鼠，随机分为正常对照组6只，模型组6只，电针治疗组6只，灸法治疗组6只，电针加雌激素治疗组6只，灸法加雌激素治疗组6只，对模型组大鼠于0周摘除其卵巢。对正常对照组和模型组大鼠饲养13周后，以腹主动脉放血法处死大鼠，取大鼠肱骨进行拉伸实验，取大鼠股骨进行扭转实验，取大鼠胫骨进行压缩实验。得出了各组大鼠骨的拉伸、压缩应力、应变、弹性模量、扭转剪应力、扭转角等指标。结果表明：模型组拉伸、扭转、压缩力学性能指标均小于正常组．     

维甲酸致骨质疏松大鼠椎骨压缩、弯曲、扭转、冲击实验研究

研究正常大鼠与维甲酸致骨质疏松大鼠椎骨的力学性质,为临床提供生物力学参数。选用280~360g8、个月龄wistar雄性大鼠88只,随机分为正常对照组44只,骨质疏松模型组44只。对模型组大鼠每日灌服维甲酸(700mg.Kg-1),对2组大鼠饲养14周,以腹主动脉放血法处死大鼠,取大鼠L1-L4椎骨进行扭转、弯曲、冲击实验,取大鼠L4椎骨进行压缩实验。得出了正常对照组和模型组大鼠L4椎骨压缩最大载荷、最大应力、最大位移、最大应变及弹性模量,得出了正常对照组和模型组大鼠L1-L4椎骨三点弯曲最大载荷、最大弯矩、最大应力、弹性模量等数据,得出了正常对照组和模型组大鼠L1-L4椎骨扭转最大扭矩、扭转角、扭转剪应力、冲击实验最大冲击功、冲击韧性指标。模型组各项力学性能指标小于正常对照组(P<0.05)。     

脊髓损伤继发骨质疏松动物模型骨力学性质实验研究

目的 研究正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨力学性质,为临床提供生物力学参数.方法 选用280～320 g,4～5月龄wistar雄性大鼠77只,随机分为0周空白对照组11只,3周对照组11只,7周对照组11只,11周对照组11只,三周实验组11只,7周实验组11只,11周实验组11只.0周空白组于0周处死,解剖取大鼠股骨、胫骨、肱骨,以生理盐水浸温的纱布包裹,置-20℃冰箱内保存备用.对3、7、11周对照组大鼠以咬骨钳将其椎板咬开,不破坏硬膜和脊髓,人为造成脊髓损伤后饲养,复制骨质疏松模型.分别于3、7、11周处死对照组和实验组大鼠.取大鼠股骨进行压缩实验,取肱骨进行剪切实验,取胫骨进行扭转实验.结果 得出了各组大鼠股骨压缩力学性能指标、肱骨剪切力学性能指标和胫骨扭转力学性能指标.结论 实验组和对照组的各项力学性能指标显著低于0周空白组(P＜0.05).     

去势大鼠所致骨质疏松对骨生物力学性质影响的实验研究

研究了正常大鼠和去势(摘除卵巢)所致大鼠骨质疏松大鼠骨的弯曲、拉伸实验和应力松弛、蠕变实验。选用280～320g,4～5月龄wistar雌性大鼠50只,随机分为正常对照组25只,模型组25只。对模型组大鼠于0周摘除其卵巢。对正常对照组和模型组大鼠饲养14周,以腹主动脉放血法处死大鼠。取大鼠股骨进行弯曲实验,取肱骨进行拉伸实验,还对大鼠股骨进行应力松弛蠕变实验。得出了正常对照组和模型组大鼠肱骨拉伸力学性能指标,正常组和对照组大鼠肱骨弯曲力学性能指标,还得出了正常组和模型组大鼠股骨应力松弛、蠕变实验数据和典线。对应力松弛、蠕变实验数据进行归一化处理,得出了归一化应力松弛函数,归一化蠕变函数及曲线。对实验数据进行回归分析,得出了回归系数和G(t)、J(t)表达式。实验结果表明:模型组各项力学性能指标均显著低于正常对照组。     

大鼠脊髓损伤继发骨质疏松生物力学性质实验研究

研究了正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨的生物力学性质。选用280g～320g4月～5月龄Wistar雄性大鼠70只，随机分为0周空白对照组10只，3周对照组10只，7周对照组10只，11周对照组10只，三周实验组10只，7周实验组10只，11周实验组10只，0周空白组于0周处死，解剖取大鼠股骨、胫骨、肱骨，以生理盐水浸温的纱布包裹，置-20℃冰箱内保存备用。对3周、7周、11周对照组大鼠以咬骨钳将其椎板咬开，不破坏硬膜和脊髓，进行饲养。对3周、7周、11周实验组大鼠人为造成脊髓损伤后饲养，复制骨质疏松模型。分别于3周、7周、11周处死对照组和实验组大鼠。取0周空白组和11周实验组胫骨制作脱钙切片进行骨组织形态观察。 取大鼠股骨进行弯曲实验，取肱骨进行拉伸实验，取胫骨进行冲击实验。取0周空白组、3周实验组、7周实验组、11周实验组大鼠股骨进行应力松弛、蠕变实验，得出了各组大鼠肱骨拉伸力学性能指标、各组大鼠股骨弯曲力学性能指标，各组大鼠胫骨冲击性能指标和大鼠股骨0周，3周、7周、11周对照组大鼠股骨应力松驰、蠕变数据及曲线。实验结果表明，模型组和对照组的各项力学性能指标显著低于0周空白组（P〈0．05）。对脊髓损伤导致大鼠骨质疏松对骨力学性能指标的影响进行分析讨论。     

国人股骨下端松质骨力学性质实验研究

对正常国人新鲜尸体股骨下端松质骨的拉伸、压缩、扭转、剪切、弯曲、冲击等力学性能进行实验研究,得出了股骨下端松质骨纵向的拉伸、压缩破坏载荷、强度极限、弹性模量,扭转破坏扭矩、扭转剪切强度极限,扭转剪切弹性模量,剪切破坏载荷、剪切强度极限,弯曲破坏载荷、弯曲强度极限,冲击功、冲击韧性指标.对松质骨的取样方法及松质骨拉伸,扭转试样固定装夹方法进行探讨.对股骨下端松质骨的力学性质进行分析讨论.     

几种治疗方法治疗骨质疏松动物骨力学实验研究

目的 研究去势所致大鼠骨质疏松以电针、灸法、电针加雌激素、灸法加雌激素治疗后大鼠骨的力学性质,为临床提供生物力学参数.方法 选用280～320 g,4～5月龄Wistar雌性大鼠48只,随机分为正常对照组8只,实验组48只,包括正常对照组8只,模型组8只,电针治疗组8只,灸法治疗组8只,电针加雌激素治疗组8只,灸法加雌激素治疗组8只.对实验的大鼠于O周摘除其卵巢.大鼠饲养13周后,以腹主动脉放血法处死大鼠,取大鼠股骨进行弯曲实验,取大鼠胫骨进行冲击实验,取大鼠肱骨进行剪切实验.结果 得出了各组大鼠骨的弯曲应力、应变、弹性模量.剪切剪应力、应变,冲击实验冲击功、冲击韧性等指标.结论 针法、灸法、雌激素对骨质疏松大鼠有一定治疗作用,对维持骨的力学特性具有一定的积极作用.     

去势大鼠所致骨质疏松对骨的黏弹性力学性质影响

目的 研究了正常大鼠和去势所致大鼠骨质疏松大鼠骨的应力松弛、蠕变力学性质,为临床提供生物力学参数.方法 选用280～320g,4～5月龄Wistar雌性大鼠50只,随机分为正常对照组25只,模型组25只.对模型组大鼠于0周摘除其卵巢.对正常对照组和模型组大鼠饲养14周后,以腹主动脉放血法处死大鼠,取大鼠股骨进行压缩试验,取大鼠胫骨进行冲击试验,还取大鼠股骨进行压缩应力松弛、蠕变实验.结果 得出了大鼠股骨压缩力学性能指标和大鼠胫骨冲击力学性能指标,得出了正常组和模型组大鼠股骨应力松弛、蠕变实验数据和曲线,对应力松弛、蠕变实验数据进行归一化处理,得出了归一化应力松弛函数,归一化蠕变函数及曲线.对实验数据进行同归分析,得出了同归系数和G(t)、J(t)表达式.结论 模型组压缩和冲击力学性能指标和7200s应力松弛量、蠕变量均小于正常组.     

脊髓损伤继发骨质疏松大鼠椎骨的力学变化

背景：脊髓损伤造成下肢肌肉萎缩,久之引起骨质疏松,为了解脊髓损伤继发骨质疏松的发病机制,有必要对脊髓损伤继发骨质疏松动物模型骨进行生物力学性质研究。 目的：观察脊髓损伤所导致骨的力学变化。 方法：选用Wistar雄性大鼠66只,随机分为空白组和模型组。模型组大鼠于T10椎体水平剪开椎板损伤脊髓。损伤后11周解剖取大鼠L1~4椎骨,进行压缩实验、取L1~4椎骨进行扭转、冲击实验。 结果与结论：模型组压缩实验最大载荷、最大应力、最大应变,扭转实验最大转矩、最大扭转角、最大切应力,冲击实验最大冲击功、最大冲击韧性均小于空白组(P < 0.05),说明脊髓损伤继发大鼠骨质疏松后大鼠椎骨压缩、扭转、冲击力学特性发生改变。     

骨质疏松对骨生物力学性质影响实验研究

研究了正常大鼠股骨和维甲酸所致大鼠骨质疏松股骨的生物力学性质。选用了 175 g～ 2 4 5 g ,3月龄～ 4月龄Wistar大鼠 6 0只 ,随机分为正常对照组 30只 ,模型组 30只。对模型组大鼠灌服维甲酸 (70mg·kg-1·d-1) 2周 ,实验第 12周末处死大鼠 ,测定股骨骨密度。取胫骨制作脱钙切片 ,进行骨组织形态观察。取股骨进行拉伸、冲击实验和应力松弛、蠕变实验。测定股骨生物力学性能指标 ,得出了正常对照组和模型组股骨的拉伸应力、应变数据等。还得出冲击功、冲击韧性、应力松弛 ,蠕变数据和曲线。对应力松弛蠕变实验数据进行归一化处理 ,得出归一化应力松弛函数、蠕变函数及曲线。实验结果表明模型组的各项力学性能指标显著低于正常对照组 (P <0 .0 5 )。对骨质疏松对力学性能指标的影响进行分析讨论。     

骨质疏松动物模型治疗的黏弹性实验研究

研究了正常大鼠去势所致骨质疏松大鼠和以电针、灸法、雌激素、电针加雌激素、灸法加雌激素治疗组大鼠骨的压缩、应力松弛、蠕变等力学性质.选用280～320g,4～5月龄Wistar雌性大鼠50只,随机分为正常对照组8只,骨质疏松模型组7只,电针治疗组7只,灸法治疗组7只,雌激素治疗组7只,电针加雌激素治疗组7只,灸法加雌激素治疗组7只,对实验组大鼠于0周摘除其卵巢.各组大鼠饲养40周后,以腹主动脉放血法处死大鼠.取大鼠胫骨进行压缩应力松弛、蠕变实验,得出各组大鼠胫骨应力松弛、蠕变数据和曲线,以三参数模型进行处理,拟合应力松弛、蠕变曲线,得出了各组应力松弛、蠕变方程.结果表明,正常组和治疗组7200s应力松弛量和蠕变量大于模型组(P＜0.05).     

WKY大鼠与自发性高血压模型大鼠(SHR)大脑中动脉拉伸力学特性的对比分析

对比分析WKY大鼠和SHR大鼠大脑中动脉的拉伸力学特性,为预防高血压提供生物力学基础。取5月龄正常WKY雄性大鼠大脑中动脉20个,5月龄SHR雄性大鼠大脑中动脉20个,试样以0.5mm/Min的实验速度进行纵向拉伸实验。WKY雄性大鼠大脑中动脉组拉伸最大应力、最大应变、弹性限度应变大于SHR雄性大鼠大脑中动脉组(P0.05),SHR雄性大鼠大脑中动脉的弹性模量值大于WKY雄性大鼠大脑中动脉(P0.05)。WKY大鼠大脑中动脉和自发性高血压模型大鼠(SHR)大脑中动脉具有不同的拉伸力学特性,自发性高血压模型大鼠(SHR)大脑中动脉拉伸力学特性发生了改变。     

Biomechanical changes in long limb bones of HAN-Wistar rats during postnatal development

Summary From a total of 648 male and 638 female HAN-Wistar rats the bones of 12 males and 12 females were examined at seven week intervals from the 35th to the 1129th day after birth. Biomechanical properties of the femora, tibiae and humeri were defined in a bending test using a tension testing machine. Load deflection diagrams in bending were produced, and the values of maximum bending load, bending breaking load, maximum deflection and ultimate deflection were correlated to age, body weight and bone length. The mean values of weight, bone length and biomechanical data are significantly higher in male rats. In both sexes biomechanical properties show a clear dependence on age. Up to the age of 330 days the tibia is more flexible than the femur or humerus. Values of partial correlation coefficients demonstrate that weight exerts more influence on the biomechanical properties of bones than age or bone length. With increasing weight, the loading capacity of bones rises in both sexes.This study was supported by the Deutsche Forschungsgemeinschaft     

成骨生长肽羧基端片段及其衍生物对去卵巢大鼠骨生物力学性能的影响

目的探讨成骨生长肽羧基端片段(OGP10-14)及其衍生物G38I和G38K对去卵巢(OVX)骨质疏松大鼠股骨和腰椎生物力学性能的影响。方法56只3月龄SD雌性大鼠分为7组,1～6组行OVX手术,术后1～3组分别给予观察药物OGP(10-14)、G38I和G38K,4、5组分别给予利塞磷酸钠及阿伦磷酸钠作为治疗对照,6组术后给予安慰剂,7组为假手术组。术后第60天处死,分离股骨行三点弯曲实验,腰椎行压缩实验,检测并分析各组生物力学有关指标。结果OVX术后大鼠腰椎强度极限及最大应变分别下降为假手术组的80%和65%,变化较股骨明显,说明骨质疏松症早期,以松质骨为主的部位受累更加显著。OGP(10-14)及其衍生物治疗后,G38I,G38K组股骨弹性弯曲应力较OVX组显著升高,最大弯曲应力、弹性模量也有升高趋势,但差异无显著性。腰椎强度极限OGP(10-14)组升高达OVX组的1.28倍(P<0.01),与二磷酸盐治疗组近似,弹性模量OGP(10-14)组为OVX组的1.35倍。结论OGP(10-14)及其衍生物治疗后,在一定程度上提高了骨质疏松大鼠骨组织抗冲击、抗压缩的能力,改善了骨生物力学性能。     

骨质疏松对骨的粘弹性性质影响的实验研究

目的研究正常大鼠股骨和维甲酸所致大鼠骨质疏松股骨的压缩粘弹性性质,为临床提供生物粘弹性力学参数。方法选用175～245g,6月龄Wistar大鼠30只,随机分为正常对照组15只,模型组15只。对模型组大鼠每日灌服维甲酸(70mg·kg-1·d-1),实验动物于第12周末处死。取股骨进行压缩应力松弛、蠕变实验。结果得出了正常对照组和模型组股骨应力松弛,蠕变数据和曲线。对应力松弛蠕变实验数据进行归一化处理,得出归一化应力松弛函数、蠕变函数及曲线。结论模型组的7200s应力松弛、蠕变量指标显著低于正常对照组(P<0.05)。     

股骨—人工假体之间的界面生物力学分析

目的 对股骨-人工假体之间的界面生物力学进行分析。方法 应用非均质层状材料弯曲和扭转理论计算模型，定量分析了单足站立相及坐位起立时股骨干在不同假体植入前、后的应力分布情况。结果 由于股骨-假体界面两边材料性能不同，产生的较大应力差异是引起界面松动、剥离和损坏的生物力学原因。不同假体的弹性模量不同，产生应力遮挡的程度不同。结论 复合材料假体植入后应力遮挡率最低。羟磷灰石表面涂层假体能缓和界面层的应力差异。     

青年与老年肋骨扭转力学特性对比分析

选择胸椎骨折固定器需要了解肋骨的力学特性.本文对正常国人青年和老年尸体肋骨进行扭转实验,并对比分析青年和老年尸体肋骨的扭转力学特性,为临床提供生物力学参数.实验标本取自4具正常国人男性新鲜尸体肋骨,年龄分别为23岁、27岁、72岁、76岁,根据年龄分为青年组和老年组.以肋骨标本沿纵向切成长55mm的样本试样,每组各20个.实验环境温度为20℃,将样本两端装夹于扭转试验机的夹头内,以1°/s的扭转速度对试样施加扭矩,测试样本破坏后的最大扭矩和最大扭转角值,并计算其扭转切应力,同时观察样本破坏断口的形貌.实验结果表明,青年组肋骨最大扭矩、切应力和扭转角均大于老年组,有显著性差异（P 〈 0.05）,因此青年组和老年组肋骨具有不同的扭转力学特性.样本断口形貌显示,2组样本断口多数为斜型,少数为横型.大体观察,青年组肋骨骨小梁排列细密,老年组肋骨骨小梁排列稀疏,具有老年骨质疏松的特征.     

Comparison of the structure and mechanical properties of bovine femur bone and antler of the North American elk (Cervus elaphus canadensis)

Antler and limb bone have a similar microstructure and chemical composition. Both are primarily composed of type I collagen and a mineral phase (carbonated apatite), arranged in osteons in compact (cortical bone) sections and a lamellar structure in the cancellous (spongy or trabecular bone) sections. The mineral content is lower in antler bone and it has a core of cancellous bone surrounded by compact bone running through the main beam and tines. The mineral content is higher in the compact compared with the cancellous bone, although there is no difference in ratios of the mineral elements with calcium. Mechanical tests (bend and compression) on longitudinal and transverse orientations of dry and rehydrated compact bone of North American elk (Cervus elaphus canadensis) antlers are compared with known data on other antlers as well as bovine femora. Both dry and rehydrated bones are highly anisotropic, with the bending and compressive strength and elastic modulus higher in the longitudinal than in the transverse direction. There is no significant difference between the bend strength and elastic modulus between dry and rehydrated samples tested in the transverse direction. The elastic modulus measured from the bending tests is compared with composite models. The elastic modulus and bend strengths are lower in the rehydrated condition, but the strain to failure and fracture toughness is much higher compared with dry samples. All antler bone mechanical properties are lower than that of bovine femora. The antler has a much higher fracture toughness compared with bovine femora, which correlates with their main function in intraspecific combat as a high impact resistant, energy absorbent material. A model of compression deformation is proposed, which is based on osteon sliding during shear.     

股骨头松质骨力学性质实验研究

目的 研究股骨头松质骨力学性质，为临床提供生物力学参数。方法 对正常国人新鲜尸体股骨头松质骨的拉伸、压缩、扭转、剪切、弯曲、冲击力学性能进行实验研究。结果 得出了股骨头松质骨的拉伸、压缩破坏载荷、强度极限、弹性模量，扭转破坏扭矩、扭转剪切强度极限，弯曲破坏载荷、弯曲强度极限、剪切破坏载荷、剪切强度极限，冲击功、冲击韧性等测试指标的实验结果。结论 股骨头松质骨抗压强度大于抗拉强度，压缩弹性模量大于拉伸弹性模量，扭转强度大于剪切强度，抗弯强度与抗压强度接近。     

Decreased femoral diaphyseal mechanical strength mainly due to qualitative impairment of cortical tissue in growing rats with stress erythropoiesis

Stress erythropoiesis (SE) can be defined as a state of increased red cell production in response to an enhanced secretion of erythropoietin. Under normal conditions, erythropoiesis in the adult occurs in the erythropoietic tissue that is confined to the bone marrow within the skeleton. Hypertrophy of the erythropoietic marrow that occurs during SE must be accommodated in a larger space. The resulting expansion of the marrow space may induce bone resorption and could alter the biomechanical performance of bone. The present study was designed to estimate the effect of sustained SE on diaphyseal structure and biomechanics of rat femur by mechanically testing the diaphyseal stiffness and strength and calculating some indicators of bone material properties. Female Sprague–Dawley rats weighing 100.0 ± 5.2 g were divided in a control (C) and an experimental (E) group. E rats were biweekly injected with 60 mg/kg of phenylhydrazyne during 6 weeks to induce a haemolytic state. SE, in response to haemolysis, was estimated by reticulocyte count and erythrokinetic techniques, which were markedly increased. To assess bone mechanical properties, the right femur was tested in three-point bending test. Sections of the left femur were stained with haematoxylin–eosin. Body growth was not altered by treatment. Diaphyseal bone mass (CSA) was 13% lower in E than in C rats, while the cross-sectional bending moment of inertia (xCSMI) was significantly higher. The “load capacity” extrinsic properties of the femoral diaphysis were about 40% decreased in E rats when compared to C ones, while the bone material quality indicators (elastic modulus and yield stress of cortical bone tissue) were 54 and 38% lower, respectively. The histologic sections of E femora exhibited a marked thinning of cortical bone and the presence of woven bone in the medullary compartment. The results obtained in this study indicate that SE caused the impairment of the diaphyseal bone material properties (elastic modulus and elastic stress) but enhanced xCSMI over the control values. Neither this improvement in diaphyseal cross-sectional design nor the formation of woven bone could offset the impairment in the bone material stiffness. It is thus proposed that the biomechanical impact of SE upon the whole-bone stiffness should have been more determined by the negative effect on bone material quality than by the negative changes in the cortical area.