INDEPENDENT FUNCTIONS OF 2 HEADS OF LATERAL PTERYGOID MUSCLE
INDEPENDENT FUNCTIONS OF 2 HEADS OF LATERAL PTERYGOID MUSCLE
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DOI：
10.1002/aja.1001380206
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发表时间：
1973-01-01
影响因子：
--
通讯作者：
MCNAMARA, JA
中科院分区：
文献类型：
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作者：
MCNAMARA, JA
翼外肌在下颌运动中的作用的调查一直受到限制，由于在人类受试者中获得一致的神经肌肉记录的困难。恒河猴被用作替代实验动物。对33只猕猴进行了113次肌电记录。两个不同的功能模式被确定从翼外肌的区域，这取决于该肌肉内的电极的位置。通过对12只动物的电极放置区域进行解剖，发现这两种活动模式与翼外肌的下头和上级头有关。下颌骨下头与舌骨上肌群在下颌骨的张开运动中起协同作用。在闭合运动或吞咽中未观察到活动。相反，上级头在打开运动期间不活跃。肌电图活动的上级头，拮抗舌骨上肌，观察到在这样的关闭运动，如咀嚼和咬紧的牙齿，并在吞咽。在下颌骨的闭合运动期间，上级头可能将髁头和椎间盘定位或稳定在关节隆起上，而在打开运动期间，下级头协助髁头向下、向前和对侧平移。因此，翼外肌的两个头可以被认为是两个功能不同的肌肉。
Investigations on the role of the lateral pterygoid muscle in mandibular movements have been limited due to difficulties in obtaining consistent neuromuscular recordings in human subjects. The rhesus monkey was used as a substitute experimental animal. Thirty-three Macaca mulatta were monitored in 113 electromyographic recording sessions. Two distinct functional patterns were identified from the region of the lateral pterygoid muscle, depending upon the location of the electrodes within this muscle. Through anatomical dissection of areas of electrode placement in 12 animals, the two patterns of activity were related to the inferior and superior heads of the lateral pterygoid muscle. The inferior head acted synergistically with the suprahyoid muscle group in opening movements of the mandible. No activity was noted in closing movements, or in swallowing. In contrast, the superior head was not active during opening movements. Electromyographic activity of the superior head, antagonistic to the suprahyoid muscles, was observed during such closing movements as chewing and clenching of the teeth and during deglutition. The superior head presumably positioned or stabilized the condylar head and disc against the articular eminence during closing movements of the mandible, while the inferior head assisted in the translation of the condylar head downward, anteriorly, and contralaterally during opening movements. Thus, the two heads of the lateral pterygoid can be considered as two functionally distinct muscles.