Taylor D, Lee T C
Trinity Centre for Bioengineering, Mechanical Engineering Department, Trinity College, Dublin 2, Ireland.
J Anat. 2003 Aug;203(2):203-11. doi: 10.1046/j.1469-7580.2003.00194.x.
This paper reports on the development of a theoretical model to simulate the growth and repair of microdamage in bone. Unlike previous theories, which use simplified descriptions of damage, this approach models each individual microcrack explicitly, and also models the basic multicellular units (BMUs) that repair cracks. A computer simulation has been developed that is capable of making a variety of predictions. Firstly, we can predict the mechanical behaviour of dead bone in laboratory experiments, including estimates of the number of cycles to failure and the number and length of microcracks during fatigue tests. Secondly, we can predict the results of bone histomorphometry, including such parameters as BMU activation rates and the changing ratio of primary to secondary bone during ageing. Thirdly, we can predict the occurrence of stress fractures in living bone: these occur when the severity of loading is so great that cracks grow faster than they can be repaired. Finally, we can predict the phenomenon of adaptation, in which bone is deposited to increase cortical thickness and thus prevent stress fractures. In all cases results compare favourably with experimental and clinical data.
本文报道了一种用于模拟骨微损伤生长与修复的理论模型的开发。与以往使用损伤简化描述的理论不同，该方法明确地对每个微裂纹进行建模，同时也对修复裂纹的基本多细胞单元（BMU）进行建模。现已开发出一种能够做出各种预测的计算机模拟。首先，我们可以预测实验室实验中死骨的力学行为，包括失效循环次数的估计以及疲劳试验期间微裂纹的数量和长度。其次，我们可以预测骨组织形态计量学的结果，包括诸如BMU激活率以及衰老过程中初级骨与次级骨的变化比例等参数。第三，我们可以预测活体骨中应力性骨折的发生：当负荷严重程度极大以至于裂纹生长速度超过其修复速度时，就会发生应力性骨折。最后，我们可以预测适应性现象，即骨沉积以增加皮质厚度从而防止应力性骨折。在所有情况下，结果与实验和临床数据相比都很理想。
