Acupuncture is an ancient Chinese method to treat diseases and relieve pain. Electro-acupuncture (EA) is one of many physical measures used to relieve musculoskeletal pain and to improve the associated restricted range of motion. Furthermore, electrical stimulation via skin patch electrodes is as effective as EA. Low frequency (2 Hz) and high frequency (100 Hz) of EA selectively induces the release of enkephalins and dynorphins in both experimental animals and humans. Clinical studies suggest its effectiveness for the treatment of various types of pain and spinally induced muscle spasm (24). In addition, acupuncture-like stimulation exerts physiologic effects on the central nervous system, mediated presumably by muscle afferent fibers. The effects may be relevant to relief of muscle spasm and musculoskeletal pain, and restoration of mobility (25). Moreover, the combined method of acupuncture with pressure on otopoints (the combination group) was used to treat with facial spasm. The total effective rates of the combination group, the acupuncture group and the pressure on otopoints group were 95.4%, 92.1% and 62.5% respectively; and the cure rates were 38.4%, 15.8% and 5% respectively. The differences in results of the three groups indicated that the therapeutic effectiveness of the combined method of acupuncture with pressure on otopoints is better than the other two therapeutic methods (26).These data hit the potential benefits of combination of EA and physical therapy. Moreover, electrical stimulation via skin patch electrodes is as effective as EA (24). Therefore, the effects of physical therapy combined with skin patch electrodes with different frequency maybe better than physical therapy alone following CCRT or RT are another interesting issue to discuss. Therefore, we designed the current prospective measurement study with 3 years of follow-up to evaluate the incidence and severity of radiation-induced trismus after IMRT and HT following physical therapy with or without electrical stimulation via skin patch electrodes using MRI to assess relevant pretreatment factors, treatment-related factors, and dosimetric parameters.