健康人下颌运动时头颈肩部肌电活动的研究

目的　研究健康人的下颌息止位及运动时头颈肩部肌的协同活动。方法　用肌电积分值记录分析的方法调查 1 0名健康成人的下颌息止位和各种运动时颞肌前后腹、胸锁乳突肌和斜方肌的肌电活动。结果　无论在下颌息止位还是下颌运动中 ,胸锁乳突肌和斜方肌均有相应活动 ,胸锁乳突肌活动的增加倍数与颞肌前后腹活动的增加倍数有密切的正相关关系。斜方肌在不伴咬合的各种下颌运动时活动增加 ,而在大力咬牙和咀嚼时活动趋于停止。下颌不发生偏斜时 ,同一肌的左右两侧肌的活动有密切的正相关关系。结论　颞肌前后腹、胸锁乳突肌和斜方肌均参与维持下颌息止位及下颌运动。下颌功能和头颈肩部肌功能有密切关系

Electromyography activities of the head,neck and upper trunk muscles with mandibular movement in normal adults

OBJECTIVE: To investigate the activities of head, neck and upper trunk muscles with mandibular movement in normal adults. METHODS: The integral data of surface electromyography (EMG) had been recorded to analyze the activities of anterior temporal (Ta), posterior temporal (Tp), sternocleidomastoid (SCM) and trapezius (TRAP) muscles with mandibular movement in ten normal adults. RESULTS: The former mentioned muscles acted constantly when the mandible was in the rest position. The activities of Ta, Tp and SCM muscles increased with protrusion of mandible, mouth opening, tapping, maximum clenching, and chewing movements. The amplitudes of the increased activity of these muscles were correlated significantly with each other. When the activities of Ta and Tp muscles increased to 56 times and 25 times respectively, the activity of SCM muscle increased to 5 - 6 times. The activity of trapezius muscle increased with protrusion of mandible and opening movement, but tended to stop with the maximum clenching and chewing movement. The correlations of left and right sides of the same muscles had been found. CONCLUSIONS: The muscles of head, neck and upper trunk can act as contributors to keep the mandibular positions and take part in the mandibular movements.