Effects of loading frequency on mechanically induced bone formation
Effects of loading frequency on mechanically induced bone formation
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DOI：
10.1359/jbmr.2001.16.5.918
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发表时间：
2001-05-01
影响因子：
6.2
通讯作者：
Turner, CH
中科院分区：
文献类型：
--
作者：
Hsieh, YF;Turner, CH
机械负荷对骨组织的合成代谢作用由负荷频率调节。本研究的目的是表征成年雌性大鼠尺骨骨干的骨膜和内皮质表面对受控动态载荷的响应，并检查应变大小、载荷频率和骨形成率 (BFR/BS) 之间的相互作用（频率范围为 1 至 10 Hz）。对 60 只成年雌性大鼠的尺骨施加循环压缩载荷，将其分为 12 个载荷组。每天施加 360 个周期的负载，峰值负载范围为 4.3 至 18N，频率为 1、5 和 10 Nz。负载两周后，使用双标记组织形态计量学对中干横切面进行量化，对尺骨骨膜和皮质内表面的骨形成进行定量。骨膜骨形成以剂量反应方式增加，在所测试的三个负载频率中的每个频率处具有峰值负载。加载频率显着影响峰值应变与 BFR/BS (p < 0.001) 以及峰值应变与矿化表面 (MS/BS; p < 0.001) 曲线的 x 截距和斜率。骨膜成骨最好通过数学模型来预测，该模型假设：（1）骨细胞被流体剪切应力激活，（2）由于粘弹性，骨细胞和细胞附近的细胞外基质的刚度在较高的加载频率下增加。因此，力转导似乎涉及细胞外流体力和细胞力学之间的复杂相互作用。
The anabolic effect of mechanical loading on bone tissue is modulated by loading frequency. The objective of this study was to characterize the new bone formation on the periosteal and endocortical surfaces of the ulnar diaphysis in adult, female rats in response to controlled dynamic loading and to examine the interactions between strain magnitude, loading frequency, and bone formation rate (BFR/BS) for frequencies ranging from 1 to 10 Hz. Cyclic, compressive loading was applied to the ulnas of 60 adult, female rats divided into 12 loading groups. Loading was applied for 360 cycles/day with peak loads ranging from 4.3 to 18N at frequencies of 1, 5 and 10 Nz. After 2 weeks of loading, bone formation on the periosteal and endocortical surfaces of the ulna was quantified using double-label histomorphometry on transverse sections obtained at the middiaphysis. Periosteal bone formation increased in a dose-response manner with peak load at each of the three loading frequencies tested. Loading frequency significantly affected the x intercepts and slopes of the peak strain versus BFR/BS (p < 0.001) and peak strain versus mineralizing surface (MS/BS; p < 0.001) curves. Periosteal osteogenesis was best predicted by a mathematical model that assumed: (1) bone cells are activated by fluid shear stresses and (2) that stiffness of the bone cells and the extracellular matrix near the cells increases at higher loading frequencies because of viscoelasticity. Consequently, mechanotransduction appears to involve a complex interaction between extracellular fluid forces and cellular mechanics.