Extracorporeal shock wave therapy (ESWT) has become an alternative in the treatment of myofascial trigger points (MTPs). Sonoelastography has evidences in quantitative assessment of MTPs.

This study tested the hypothesis that both radial ESWT (rEWST) and injection of 1% xylocaine are effective and safe treatments for active MTPs with novel analysis by sonoelastography.

Prospective, randomized single blinded clinical trial.

Patients (n=20) with active MTPs of UTM were randomized to receive either rESWT (n=10); three rESWT sessions; one session per week; 2000 rESWT impulses per session; positive energy flux density=0.10mJ/mm²) or 1% xylocaine (4ml) injection (n=10) (three injections; one injection per week). The outcome measure was the elasticity score of MTPs assessed with sonoelastography, pain (VAS score), active range of motion of the neck, and McGill scores three weeks after baseline.

Both rESWT and injection of 1% xylocaine resulted in statistically significantly (P<0.05) reduced elasticity scores, VAS scores of UTM and McGill scores, as well as statistically significantly (P<0.05) increased range of motion of the neck at three weeks after baseline. Except of a lower mean McGill sensory score after injection of 1% xylocaine compared to rESWT (−29%; P<0.05) repeated measures two-way analysis of variance followed by Bonferroni post-tests for pairwise comparisons showed no statistically significant differences between rESWT and injection of 1%xylocaine.

Both rESWT and 1% xylocaine injection are effective and safe treatments of active MTPs of UTM. Ultrasound elastography appears useful for objectively monitoring treatment success.