B mode, Doppler and ultrasound elastography imaging on active trigger point in women with myofascial pain syndrome treated by dry needling

Introduction. Myofascial pain syndrome is a common regional pain characterized with myolascial trigger points (MTrP) in the skeletal muscle fibers. Deep dry needling (DDN) is an effective method used by variety of clinicians in deactivation of these points. The aim of present study was to determine clinical effectiveness and to evaluate gray scale ultrasonography, Sono Doppler and ultrasound elastography images of upper trapezius following the DDN. Methods. Thirteen women with MTrP in the upper trapezius (28.85 +/- 7.70 years old) participated in the present study. Participants were treated with DDN during one session. Clinical outcomes were cervical range of motion (ROM), pain intensity, and pain pressure threshold (PPT). Ultrasonographic outcomes were MTrP area, intramuscular blood circulation and upper trapezius thickness and stiffness. Results. A significant decrease of pain intensity was observed after intervention in all subjects (p<.001). PPT and side bending cervical ROM had significant improvement in post treatment (p<.001). Subjects showed significantly lower stiffness and higher intramuscular circulation immediately after the DDN (p<.001). Conclusions. The present study demonstrated that DDN had immediate influences on muscle circulation, viscoelastic properties of the upper trapezius, and clinical outcome measurements. The findings of this study provide objective evidence of the effectiveness of DDN.