Martin B
Orthopaedic Research Laboratories, University of California, Davis 95616.
J Orthop Res. 1992 Nov;10(6):818-25. doi: 10.1002/jor.1100100611.
An analysis is presented of the balance between the accumulation and repair of fatigue damage in osteonal bone. Fatigue damage is defined in terms of cracks seen histologically when precautions are taken to avoid preparation artifact. The rate of occurrence of such damage is assumed to be proportional to the product of applied peak-to-peak stress, raised to a power, and the loading frequency. The rate of damage repair is assumed to be proportional to the activation rate for osteonal remodeling, and to the mean cross-sectional area of the resulting osteons. An additional factor is introduced to account for the possibility that damage provokes nearby remodeling. The theory is used to compare data from previous experiments of two types: fatigue-to-failure, and studies in which histologically observable cracks are made more numerous by repetitive loading. The analysis shows that there is a measure of agreement between the results of the two kinds of experiments, but the current data are too limited, and the results are too dependent on the mode of loading, to adequately test the theory. However, the analysis provides a framework for designing experiments to more efficiently clarify the relationships between fatigue failure, cracks seen in histologic sections, and the rate at which such cracks are repaired by osteonal remodeling.
本文对骨单位骨中疲劳损伤的积累与修复之间的平衡进行了分析。疲劳损伤是根据在采取预防措施以避免制备假象时组织学观察到的裂纹来定义的。假定这种损伤的发生率与施加的峰峰值应力的幂次方与加载频率的乘积成正比。损伤修复率假定与骨单位重塑的激活率以及由此产生的骨单位的平均横截面积成正比。引入了一个额外的因素来考虑损伤引发附近重塑的可能性。该理论用于比较先前两种类型实验的数据：疲劳至失效实验，以及通过重复加载使组织学上可观察到的裂纹数量增加的研究。分析表明，这两种实验结果之间存在一定程度的一致性，但目前的数据过于有限，且结果过于依赖加载方式，无法充分检验该理论。然而，该分析为设计实验提供了一个框架，以便更有效地阐明疲劳失效、组织学切片中观察到的裂纹以及通过骨单位重塑修复此类裂纹的速率之间的关系。
