this randomized controlled trial was designed to fill a gap in the literature regarding the most effective amplitude-modulated frequency of interferential current on pain pressure threshold, cervical ROM, and function of the neck region.
this study will be consisted of 4 groups, all groups will receive standard manual treatment commonly used for the treatment of chronic trigger points. this treatment will be conducted 3 times per week for 4 weeks. The standard treatment will consist of an intermittent neuromuscular inhibition technique.
the 3 experimental groups will receive interferential current sessions (3/week) for 4 weeks with the same parameters except for the amplitude-modulated frequency.
outcome measurements will be assessed at baseline, at 4 weeks, and at 4 weeks of the end of the treatment (follow-up).