Schwarting S, Schröder M, Stennert E, Goebel H H
ORL J Otorhinolaryngol Relat Spec. 1982;44(1):51-9. doi: 10.1159/000275567.
Four human facial muscles, platysma, m. levator labii, zygomaticus major and orbicularis oris, obtained during head and neck surgery, revealed no qualitative differences from normal human limb muscles, but differences with regard to fiber type distribution and fiber size. Mean fiber diameters of each muscle studied were largely 50% of those encountered in normal human limb muscles. Histographic analysis revealed that type II fibers were more frequent than type I fibers but that type IIB fibers were extremely scarce in number. The myofiber diameter spectrum was also larger in facial than in limb muscles, as myofibers produced variability coefficients around 325. The frequent presence of intramuscular nerve twigs and motor endplates may provide the opportunity of studying pre- and postsynaptic pathology in future studies of denervated facial muscles.
在头颈外科手术中获取的四块人类面部肌肉，即颈阔肌、提上唇肌、颧大肌和口轮匝肌，与正常人类肢体肌肉在性质上无差异，但在纤维类型分布和纤维大小方面存在差异。所研究的每块肌肉的平均纤维直径大多为正常人类肢体肌肉中纤维直径的50%。组织学分析表明，II型纤维比I型纤维更常见，但IIB型纤维数量极少。面部肌肉的肌纤维直径谱也比肢体肌肉的大，因为肌纤维产生的变异系数约为325。肌内神经小枝和运动终板的频繁存在可能为未来失神经支配面部肌肉的研究提供研究突触前和突触后病理学的机会。
