Sanders I, Rao F, Biller H F
Grabscheid Voice Center, Department of Otolaryngology, Mount Sinai Medical Center, New York, NY 10029-6574.
Laryngoscope. 1994 Apr;104(4):456-62. doi: 10.1288/00005537-199404000-00010.
Anatomical studies have demonstrated that the posterior cricoarytenoid muscle in the dog is composed of three bellies. These bellies are termed vertical, oblique, and horizontal on the basis of their orientation. The purpose of this study was to show whether each of these bellies can move the vocal fold in different ways. Ten anesthetized dogs underwent laryngectomies while paralyzed with curare. The posterior cricoarytenoid muscles were then exposed by dissecting the overlying esophageal mucosa. Electrical stimulation was applied to each belly, and the motion of the arytenoid cartilage was measured. Because the oblique belly overlies the vertical belly, they were usually stimulated together. It was found that the vertical and oblique bellies rock the arytenoid backwards while sliding it laterally, thus causing a maximal dilation of the airway. The horizontal belly caused a swiveling motion of the arytenoid. It is proposed that the vertical and oblique bellies normally cause vocal fold abduction during respiration, while the horizontal belly primarily is used to adjust finely the position of the vocal process during phonation. Because the human posterior cricoarytenoid is also composed of separate bellies it, too, may have distinct functions.
解剖学研究表明，犬的环杓后肌由三个肌腹组成。根据其方向，这些肌腹分别称为垂直肌腹、斜肌腹和水平肌腹。本研究的目的是证明这些肌腹中的每一个是否能以不同方式移动声带。十只麻醉的犬在箭毒麻痹下接受了喉切除术。然后通过解剖覆盖的食管黏膜暴露环杓后肌。对每个肌腹施加电刺激，并测量杓状软骨的运动。由于斜肌腹覆盖在垂直肌腹之上，它们通常一起受到刺激。结果发现，垂直肌腹和斜肌腹在使杓状软骨向外侧滑动的同时使其向后摆动，从而导致气道最大程度扩张。水平肌腹引起杓状软骨的旋转运动。有人提出，垂直肌腹和斜肌腹在呼吸过程中通常引起声带外展，而水平肌腹主要用于在发声时精细调整声带突的位置。由于人类的环杓后肌也由独立的肌腹组成，因此它可能也具有不同的功能。
