Chapurlat R D, Delmas P D
INSERM Research Unit 831, Université de Lyon, Hôpital E Herriot, Hospices Civils de Lyon, 69437 Lyon cedex 03, France.
Osteoporos Int. 2009 Aug;20(8):1299-308. doi: 10.1007/s00198-009-0899-9. Epub 2009 Mar 17.
Microdamage accumulation due to fatigue loading may lead to fracture. In addition, several studies using animal models have suggested in recent years that bisphosphonates might increase microdamage accumulation.
We have reviewed the literature after a PubMed search, to examine the techniques to look for microcracks, the relationship between microdamage and bone strength, and the influence of anti-osteoporosis agents.
Currently, the search for microcracks relies on bulk staining of bone samples, which are then examined on optic microscopy and fluorescence or confocal microscopy. The accumulation of microdamage is associated with fatigue loading and is likely to trigger targeted bone remodeling, especially in cortical bone. Several studies examining beagle dogs receiving bisphosphonates have shown a dose-dependent accumulation of microdamage in bone, with conflicting results regarding the consequences on bone mechanical properties. In living humans, obtaining data is limited to the iliac crest bone. The potential association between long-term bisphosphonate use and microcrack accumulation at the iliac crest bone has not been established unequivocally.
Bone microdamage is critical in the understanding of bone quality. Assessment of microdamage is technically difficult, especially in humans. The clinical impact of microdamage potentially induced by bone drugs has not been established in humans.
疲劳载荷导致的微损伤积累可能会引发骨折。此外，近年来多项使用动物模型的研究表明，双膦酸盐可能会增加微损伤积累。
我们在PubMed检索后回顾了文献，以研究寻找微裂纹的技术、微损伤与骨强度之间的关系以及抗骨质疏松药物的影响。
目前，寻找微裂纹依赖于对骨样本进行整体染色，然后在光学显微镜、荧光显微镜或共聚焦显微镜下进行检查。微损伤的积累与疲劳载荷相关，并且可能会触发靶向性骨重塑，尤其是在皮质骨中。多项针对接受双膦酸盐治疗的比格犬的研究表明，骨中微损伤呈剂量依赖性积累，但其对骨力学性能的影响结果相互矛盾。在活体人类中，获取数据仅限于髂嵴骨。长期使用双膦酸盐与髂嵴骨微裂纹积累之间的潜在关联尚未明确确立。
骨微损伤对于理解骨质量至关重要。微损伤评估在技术上具有难度，尤其是在人类中。骨药物潜在诱发的微损伤对人类的临床影响尚未确立。
