El-Essawy H
Int J Oral Surg. 1975 Apr;4(2):69-72. doi: 10.1016/s0300-9785(75)80016-0.
Locking of the temporomandibular joint is often attributed to uncoordinated muscle activity and muscle spasm. A simple experiment has been devised to test the hypothesis that locking occurs when uncoordinated elevator muscle tension (temporalis, masseter and medial pterygoid) precedes and interferes with the opening action of the lateral pterygoid muscle. By asking the patients with manifest locking to protrude prior to maximal opening (protrude-open maneuver, POM) a highly significant increase of mouth opening was found over that produced by simple maximal opening (MO). No significant difference was found in a group of patients with myofascial pain as their only symptom, or in a group of healthy controls, suggesting that pain does not contribute to the mechanism of locking.
颞下颌关节绞锁通常归因于肌肉活动不协调和肌肉痉挛。已设计了一项简单实验来检验以下假设：当不协调的升肌紧张（颞肌、咬肌和翼内肌）先于并干扰翼外肌的开口动作时，就会发生绞锁。通过让明显绞锁的患者在最大开口之前前伸（前伸 - 开口动作，POM），发现开口度比单纯最大开口（MO）时显著增加。在仅以肌筋膜疼痛为唯一症状的患者组或健康对照组中未发现显著差异，这表明疼痛与绞锁机制无关。
