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Innervation of the trapezius muscle: Is cervical contribution important to its function?

2006; Wiley; Volume: 135; Issue: 5 Linguagem: Inglês

10.1016/j.otohns.2006.05.007

1097-6817

Wen Zhao, Jian Sun, Jiawei Zheng, Jun Li, Yue He, Zhiyuan Zhang,

Transcranial Magnetic Stimulation Studies

To study the effect of the cervical plexus and the accessory nerve to the function of the trapezius muscle.Eighteen adult male Sprague-Dawley rats were randomly divided into three groups. The neurotomies were performed in the left sides and the right sides served as within-subject controls. In group A, the accessory nerve was transected. The C2-5 were transected in group B, and both of the accessory nerve and C2-5 were cut in group C. The electrophysiologic, myophysiologic, and histologic changes of the muscles were measured.There were significant differences (P < 0.05) between the three groups in the recovery rates of the transverse area of the muscles. The CMAP recorded from the experimental sides in group B were similar to the control sides. The values of the maximum tension of the tetanus contraction between the two sides showed no differences either (P > 0.05).The accessory nerve supplies the most important motor input to the trapezius. Motor innervations of the cervical plexus are not very significant.