单羽状骨骼肌平面模型的修正

Revision on the planimetric model of unipennate skeletal muscle

目的对单羽状骨骼肌的平面模型及Otten的受力分析进行修正,Otten只考虑了腱膜的平衡(局部平衡),并且对肌内压力作了过多的简化。方法新方法考虑了整体肌肉的平衡,引入一体积相关力来保持肌肉体积不变。整体肌肉的力学平衡产生了一组不同于局部平衡的肌纤维力和肌张力之间的关系式。结果新的方法提高了对鼠腓肠肌力-长度特性的预测。结论用简单的平面模型可以把肌肉的几何尺寸以及肌肉的力-长度特性关系预测得比较好,这说明在这个简单模型中所忽略的因素的影响是微小的,或者是内部之间进行了补偿。

Objective To make some revisions on the planimetric model of unipennate skeletal muscle ,as well as Otten＇s mechanical analysis since Otten only considered the equilibrium of the aponeurosis （local equilibrium） and made too much simplification on the intramuscular pressure. Method The new method in this paper is based on the mechanical equilibrium of whole muscle and a volume-related force is introduced to keep muscle volume constant. Mechanical equilibrium of whole muscle yields a different relation between fiber and muscle force, compared to relations derived when only equilibrium of aponeurosis is considered. Results The newly derived relation improves prediction of the rat gastrocnemius muscle force-length characteristics. Conclusion The prediction of muscle force-length characteristics is very good with a simple model such as a planimetric model, which suggests that the influence of properties neglected in such a simple model is either small or internally compensated in the net effects.