Sarrafzadeh J, Ahmadi A, Yassin M. The effects of pressure release, phonophoresis of hydrocortisone, and ultrasound on upper trapezius latent myofascial trigger point. Objective To compare the effects of pressure release (PR), phonophoresis of hydrocortisone (PhH) 1%, and ultrasonic therapy (UT) in patients with an upper trapezius latent myofascial trigger point (MTP). Design Repeated-measure design. Setting A pain control medical clinic. Participants Subjects (N=60; mean±SD age, 21.78±1.76y) with a diagnosis of upper trapezius MTP participated in this study. Subjects were randomly divided into 4 groups: PR, PhH, UT, and control (15 in each group). All patients had a latent MTP in the upper trapezius muscle. Interventions PR, PhH, UT. Main Outcome Measures Subjective pain intensity, pain pressure threshold (PPT), and active cervical lateral flexion range of motion were assessed in 6 sessions. Results All 3 treatment groups showed decreases in pain and PPT and an increase in cervical lateral flexion range of motion ( P<.001) compared with the control group. Both PhH and PR techniques showed more significant therapeutic effects than UT ( P<.001). Conclusions Our results indicate that all 3 treatments used in this study were effective for treating MTP. According to this study, PhH is suggested as a new method effective for the treatment of MTP.