Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fracture...Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fractures are of global health and socioeconomic importance. The three-dimensional microstructural information of the common osteoporosis-related fracture sites, including vertebra, femoral neck and distal radius, is a key for fully understanding osteoporosis pathogenesis and predicting the fracture risk. Low vertebral bone mineral density(BMD) is correlated with increased fracture of the spine. Vertebral BMD decreases from cervical to lumbar spine, with the lowest BMD at the third lumbar vertebra. Trabecular bone mass of the vertebrae is much lower than that of the peripheral bone. Cancellous bone of the vertebral body has a complex heterogeneous three-dimensional microstructure, with lower bone volume in the central and anterior superior regions. Trabecular bone quality is a key element to maintain the vertebral strength. The increased fragility of osteoporotic femoral neck is attributed to low cancellous bone volume and high compact porosity. Compared with age-matched controls, increased cortical porosity is observed at the femoral neck in osteoporoticfracture patients. Distal radius demonstrates spatial inhomogeneous characteristic in cortical microstructure. The medial region of the distal radius displays the highest cortical porosity compared with the lateral, anterior and posterior regions. Bone strength of the distal radius is mainly determined by cortical porosity, which deteriorates with advancing age.展开更多
Osteoporotic fractures are a major public health problem worldwide, but incidence varies greatly across racial groups and geographic regions. Recent work suggests that the incidence of osteoporotic fracture is rising ...Osteoporotic fractures are a major public health problem worldwide, but incidence varies greatly across racial groups and geographic regions. Recent work suggests that the incidence of osteoporotic fracture is rising among Asian populations. Studies comparing areal bone mineral density and fracture across races generally indicate lower bone mineral density in Asian individuals including the Chinese, but this does not reflect their relatively low risk of non-vertebral fractures. In contrast, the Chinese have relatively high vertebral fracture rates similar to that of Caucasians. The paradoxically low risk for some types of fractures among the Chinese despite their low areal bone mineral density has been elucidated in part by recent advances in skeletal imaging. New techniques for assessing bone quality non-invasively demonstrate that the Chinese compensate for smaller bone size by differences in hip geometry and microstructural skeletal organization. Studies evaluating factors influencing racial differences in bone remodeling, as well as bone acquisition and loss, may further elucidate racial variation in bone microstructure. Advances in understanding the microstructure of the Chinese skeleton have not only helped to explain the epidemiology of fracture in the Chinese, but may also provide insight into the epidemiology of fracture in other races as well.展开更多
骨微结构改善是骨质疏松症药物治疗的目标,可以增加骨强度,降低骨折风险,但目前来看骨微结构和骨强度的评估手段相对不足。利用有限元分析(finite element analysis,FEA)能够很好地模拟各种类型药物治疗骨质疏松症后有限元模型的各种力...骨微结构改善是骨质疏松症药物治疗的目标,可以增加骨强度,降低骨折风险,但目前来看骨微结构和骨强度的评估手段相对不足。利用有限元分析(finite element analysis,FEA)能够很好地模拟各种类型药物治疗骨质疏松症后有限元模型的各种力学状况,分析其生物力学作用机制、验证骨微结构参数变化对骨强度的影响,优化治疗方案,为药物治疗骨质疏松症的骨微结构和生物力学特性研究提供有效的研究方法。本文通过回顾近年来药物治疗骨质疏松症的有限元分析研究,探讨不同种类药物治疗骨微结构参数变化对骨强度的影响,结果发现目前关于药物治疗骨质疏松症的有限元研究有待于对骨微结构有限元模型建立进行标准化和精确化,同时进一步推广有限元研究思路,需要更多大样本的临床随机对照试验来验证疗效,更好的指导药物治疗骨质疏松症的临床运用。展开更多
目的评估高脂饮食(HFD)对骨质疏松大鼠骨密度(bone mineral density,BMD)及骨修复的影响并探讨可能的机制。方法将雌性SD大鼠随机分为三组:假手术卵巢切除组(Sham)、手术卵巢切除模型组(OVX)、手术卵巢切除模型+HFD(OVX+HFD);随后所有...目的评估高脂饮食(HFD)对骨质疏松大鼠骨密度(bone mineral density,BMD)及骨修复的影响并探讨可能的机制。方法将雌性SD大鼠随机分为三组:假手术卵巢切除组(Sham)、手术卵巢切除模型组(OVX)、手术卵巢切除模型+HFD(OVX+HFD);随后所有大鼠在双侧去卵巢手术或假手术后12周基础上制作双侧股骨干建立骨缺损模型,OVX+HFD组大鼠在股骨上接受HFD干预4周。随后使用影像学、血清学、骨生物力学以及基因水平检测来评估骨修复效果。结果与Sham组相比,OVX和OVX+HFD组的血清E2、ALP水平均显著降低(P<0.05),而TRAP水平均显著升高(P<0.05);OVX和OVX+HFD组之间有显著差异(P<0.05)。Micro-CT检测显示OVX+HFD组骨修复效果较OVX和Sham组明显降低;定量检测结果显示OVX+HFD组的BMD、Tb.N和Tb.Th显著小于OVX组(P<0.01),而Tb.Sp(P<0.05)在OVX+HFD组中明显大于在OVX组。生物力学显示HFD干预后明显降低了去卵巢大鼠骨缺损部位的机械强度,包括大鼠股骨的极限载荷、刚度、能量吸收和弹性模量(P均<0.05);基因检测表明与OVX组相比,OVX+HFD组Smad2、Smad3和GSK-3βmRNA表达显著增加(P<0.01),而Wnt1和β-cateninmRNA表达均显著降低(P<0.01)。结论HFD对骨质疏松状态下骨缺损愈合有负面影响,而这种影响可能是通过对Wnt/β-catenin信号传导抑制来实现的。展开更多
文摘Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fractures are of global health and socioeconomic importance. The three-dimensional microstructural information of the common osteoporosis-related fracture sites, including vertebra, femoral neck and distal radius, is a key for fully understanding osteoporosis pathogenesis and predicting the fracture risk. Low vertebral bone mineral density(BMD) is correlated with increased fracture of the spine. Vertebral BMD decreases from cervical to lumbar spine, with the lowest BMD at the third lumbar vertebra. Trabecular bone mass of the vertebrae is much lower than that of the peripheral bone. Cancellous bone of the vertebral body has a complex heterogeneous three-dimensional microstructure, with lower bone volume in the central and anterior superior regions. Trabecular bone quality is a key element to maintain the vertebral strength. The increased fragility of osteoporotic femoral neck is attributed to low cancellous bone volume and high compact porosity. Compared with age-matched controls, increased cortical porosity is observed at the femoral neck in osteoporoticfracture patients. Distal radius demonstrates spatial inhomogeneous characteristic in cortical microstructure. The medial region of the distal radius displays the highest cortical porosity compared with the lateral, anterior and posterior regions. Bone strength of the distal radius is mainly determined by cortical porosity, which deteriorates with advancing age.
基金supported by NIH grants K23 AR053507, a National Osteoporosis Foundation grant, and the Mary and David Hoar Fellowship Program of the New York Community Trust and the New York Academy of Medicine
文摘Osteoporotic fractures are a major public health problem worldwide, but incidence varies greatly across racial groups and geographic regions. Recent work suggests that the incidence of osteoporotic fracture is rising among Asian populations. Studies comparing areal bone mineral density and fracture across races generally indicate lower bone mineral density in Asian individuals including the Chinese, but this does not reflect their relatively low risk of non-vertebral fractures. In contrast, the Chinese have relatively high vertebral fracture rates similar to that of Caucasians. The paradoxically low risk for some types of fractures among the Chinese despite their low areal bone mineral density has been elucidated in part by recent advances in skeletal imaging. New techniques for assessing bone quality non-invasively demonstrate that the Chinese compensate for smaller bone size by differences in hip geometry and microstructural skeletal organization. Studies evaluating factors influencing racial differences in bone remodeling, as well as bone acquisition and loss, may further elucidate racial variation in bone microstructure. Advances in understanding the microstructure of the Chinese skeleton have not only helped to explain the epidemiology of fracture in the Chinese, but may also provide insight into the epidemiology of fracture in other races as well.
文摘骨微结构改善是骨质疏松症药物治疗的目标,可以增加骨强度,降低骨折风险,但目前来看骨微结构和骨强度的评估手段相对不足。利用有限元分析(finite element analysis,FEA)能够很好地模拟各种类型药物治疗骨质疏松症后有限元模型的各种力学状况,分析其生物力学作用机制、验证骨微结构参数变化对骨强度的影响,优化治疗方案,为药物治疗骨质疏松症的骨微结构和生物力学特性研究提供有效的研究方法。本文通过回顾近年来药物治疗骨质疏松症的有限元分析研究,探讨不同种类药物治疗骨微结构参数变化对骨强度的影响,结果发现目前关于药物治疗骨质疏松症的有限元研究有待于对骨微结构有限元模型建立进行标准化和精确化,同时进一步推广有限元研究思路,需要更多大样本的临床随机对照试验来验证疗效,更好的指导药物治疗骨质疏松症的临床运用。
文摘目的评估高脂饮食(HFD)对骨质疏松大鼠骨密度(bone mineral density,BMD)及骨修复的影响并探讨可能的机制。方法将雌性SD大鼠随机分为三组:假手术卵巢切除组(Sham)、手术卵巢切除模型组(OVX)、手术卵巢切除模型+HFD(OVX+HFD);随后所有大鼠在双侧去卵巢手术或假手术后12周基础上制作双侧股骨干建立骨缺损模型,OVX+HFD组大鼠在股骨上接受HFD干预4周。随后使用影像学、血清学、骨生物力学以及基因水平检测来评估骨修复效果。结果与Sham组相比,OVX和OVX+HFD组的血清E2、ALP水平均显著降低(P<0.05),而TRAP水平均显著升高(P<0.05);OVX和OVX+HFD组之间有显著差异(P<0.05)。Micro-CT检测显示OVX+HFD组骨修复效果较OVX和Sham组明显降低;定量检测结果显示OVX+HFD组的BMD、Tb.N和Tb.Th显著小于OVX组(P<0.01),而Tb.Sp(P<0.05)在OVX+HFD组中明显大于在OVX组。生物力学显示HFD干预后明显降低了去卵巢大鼠骨缺损部位的机械强度,包括大鼠股骨的极限载荷、刚度、能量吸收和弹性模量(P均<0.05);基因检测表明与OVX组相比,OVX+HFD组Smad2、Smad3和GSK-3βmRNA表达显著增加(P<0.01),而Wnt1和β-cateninmRNA表达均显著降低(P<0.01)。结论HFD对骨质疏松状态下骨缺损愈合有负面影响,而这种影响可能是通过对Wnt/β-catenin信号传导抑制来实现的。
