足肌的肌纤维型分布特征及构成比例研究

Distribution of myofiber types in foot muscles

关键词:  肌纤维型分布  足肌  形态学

Key words:  distribution of myofiber  foot muscles  morphological

摘要:

［目的］探讨足肌的肌纤维型分布特征和构成比例，对足肌功能和病理学研究提供形态学依据。［方法］取4例25~30岁（均死于非神经肌性疾病）死后12 h内的人尸两侧足肌共160块，用肌球蛋白ATP酶法，系统地研究了足部各肌的肌纤维分型、测定和统计各肌I型（慢缩）、Ⅱ型（快缩）肌纤维的构成比例。［结果］（1）足肌I型纤维的平均百分率为43%~59%（总平均为50.1%）。其中足背肌I型纤维的平均百分率为48.6%，足底肌为51.5%。足底肌分三群，内侧群I型纤维的平均百分率为55.1%，外侧群为51.5%，中间群为50.3%。在中间群内，浅层肌的I型纤维平均百分率为56.8%，深层肌为45.4%。（2）足背肌与足底肌间I型纤维的平均百分率差异无显著性意义（P>0.05）。但拇和趾的短屈肌与短伸肌之间的I型纤维的平均百分率短屈肌均高于短伸肌，两者间差异有显著性意义（P<0.05）。（3）足底肌中，内侧肌群的I型纤维平均百分率高于中间群，两者间差异有显著性意义（P<0.05）。在中间群内，浅层肌的I型纤维平均百分率高于深层肌，在统计学上两者差异有显著性意义（P<0.01）。（4）左、右侧比较，I型纤维的平均百分率差异无显著性意义（P>0.05）。［结论］本研究为国人肌纤维型研究提供了基础资料。

Abstract:

［Objective］To provide morphological data about the fiber types of the foot muscles for further functional and pathological investigations.［Methods］One hundred and sixty Samples of foot muscles were obtained from 4 cadavers (3 males,1 female) at the age 25~30 without neuromuscular diseases. By myosin ATPase histochemical method, fibers of the foot muscles may be divided in to TypeⅠ(slow twitching) and TypeⅡ(fast twitching).［Results］(1)The mean percentage of type I fibers of foot muscles were 43%~59%(the total mean was 50.1%).In the muscles of the dorsum of foot the mean percentage of typeⅠfibers was 48.6%.The muscles of the sole were divided into three groups medial, lateral and intermediate. In medial group the mean percentage of TypeⅠfibers was 55.1%, in the lateral group was 51.5%,and in the intermediate group was 50.3%.Among the intermediate group, the mean percentage of type I fibers of superficial muscles was 56.8%,the deep muscles was 45.4%. (2) Among them,the mean percentage of type I fibers of muscles on the dorsum of foot were 48.6%,on the sole of the foot were 51.5%,there were no significant differences between them.But the differences of type I fibers between flexor hallucis brevis,flexor digitorum brevis and extensor digitorum brevis were significant (P<0.05). (3) Among all the muscles on plantar surface of foot,the mean percentage of type I fibers in the medial group is higher than in the intermediate group (P<0.05).Among the intermediate group,the mean percentage of type I fibers of superficial muscles was higher than that of deep muscles, and there was significant difference between superficial and deep muscles(P<0.05). (4) There was apparent difference of type I fibers between the right and the left sides of foot muscles.［Conclusions］This study prorvide a basic data for my ofiber types research.