肌肉动力与断端显微位移的动态观察

目的：观察骨折愈合过程中不同时期肌力和位移的变化，探讨肌肉动力在骨折愈合中的作用。方法：采用肌力和位移传感器，测试夹板固定下兔胫骨干闭合骨折后的肌力与位移变化，计算机同步数据采集。结果：正常肌力5．04kg，伤后第一天肌力1．87kg，位移0．87mm；7天对肌力3．35kg，位移最大为1．02mm；14天对肌力接近正常5．01kg（P＞0．05）；21天对肌力恢复正常，位移下降至0．28mm；35天时位移仅为0．035mm，骨折愈合。结论：肌肉动力为骨折端提供间歇性生理应力为骨折愈合所必需，骨折愈合的最佳应力是该部生理状态下所承受的肌力。在功能活动时允许断端一定范围的纵向活动，能促进骨折愈合。

The Dynamic Observation on the myodynamia and the Microdisplacement between the Fracture Segments

Aim To investigate the changes of muscle force and displacement in different periods of fracture healing process and to inquire into the effect of myodynamia on healing of fracture. Methods The changes of muscle force and displacement of rabbits' tibial shaft closed fracture fixed with splints were measured by muscle force and displacement transducer, with the data collected synchronously by computer. Results The normal muscle force is 5. 04kg; at the first day after injury, the muscle force is 1. 87kg and the displacement is 0. 87mm; one week after injury, the muscle force is 3. 35kg and the displacement is 1. 02mm; two weeks after injury, the muscle force is close to the normal level, 5. 01kg (P> 0. 05) ; three weeks after injury, the muscle force is recovered to normal and the displacement is decreased to 0. 28mm; and five weeks after injury, the displacement is 0. 035mm and the fracture is healed. Conclusion The intermittent physiological stress at the fracture site provided by myodynamia is necessary for the healing of fracture and the optimal stress for fracture healing is produced by the muscle force under the physiofogical state. Permitting a limited longitudinal motion,during the functional training, can accelerate the fracture healing.