Fracture Healing in Mice under Controlled Rigid and Flexible Conditions Using an Adjustable External Fixator
Fracture Healing in Mice under Controlled Rigid and Flexible Conditions Using an Adjustable External Fixator
复制标题
DOI：
10.1002/jor.21148
复制
发表时间：
2010-11-01
影响因子：
2.8
通讯作者：
Ignatius, Anita
中科院分区：
文献类型：
--
作者：
Roentgen, Viktoria;Blakytny, Robert;Ignatius, Anita
小鼠越来越多地用于研究骨折愈合中的机械生物学。需要标准化的模型，允许调整断裂间隙中的机械条件。我们介绍了这样一个模型，使用刚性和柔性外固定器具有相当不同的刚度（轴向刚度分别为18.1和0.82 N/mm）。两种固定器均用于稳定C57 BL/6小鼠股骨中0.5 mm的截骨术间隙（各n = 8）。三点弯曲试验、mu CT和组织形态计量学显示21天后不同的愈合模式。两种固定均诱导膜内骨化和内软骨骨化混合的愈伤组织形成。在灵活的条件下，骨痂的抗弯刚度显着降低，并形成一个较大的，但质量较差的骨痂，骨的比例显着降低，但软骨和软组织的比例较高。对动物运动和地面反作用力的监测表明，生理负荷在组间无显著差异，表明愈合差异并非基于不同的负荷行为。总之，与更刚性的情况相比，小鼠股骨的柔性外部骨折固定导致骨折愈合延迟。(C)2010年骨科研究学会。由威利期刊公司出版骨科研究杂志28：1456-1462，2010
Mice are increasingly used to investigate mechanobiology in fracture healing. The need exists for standardized models allowing for adjustment of the mechanical conditions in the fracture gap. We introduced such a model using rigid and flexible external fixators with considerably different stiffness (axial stiffnesses of 18.1 and 0.82 N/mm, respectively). Both fixators were used to stabilize a 0.5 mm osteotomy gap in the femur of C57BL/6 mice (each n = 8). Three-point bending tests, mu CT, and histomorphometry demonstrated a different healing pattern after 21 days. Both fixations induced callus formation with a mixture of intramembranous and enchondral ossification. Under flexible conditions, the bending stiffness of the callus was significantly reduced, and a larger but qualitatively inferior callus with a significantly lower fraction of bone but a higher fraction of cartilage and soft tissue was formed. Monitoring of the animal movement and the ground reaction forces demonstrated physiological loading with no significant differences between the groups, suggesting that the differences in healing were not based on a different loading behavior. In summary, flexible external fracture fixation of the mouse femur led to delayed fracture healing in comparison to a more rigid situation. (C) 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28: 1456-1462, 2010