Effectiveness of ultrasound combine transcutaneous electrical nerve stimulation (TENS) in treatment of upper trapezius myofascial pain : a randomized controlled trial

Abstract

Myofascial pain syndrome (MPS) is one of the most common causes of musculoskeletal pain. Among various therapeutic approaches, the simultaneously combined treatment using ultrasound and transcutaneous electrical nerve stimulation (or US-TENS) may provide a novel curative strategy for MPS victims. We assessed the simultaneously combined treatment using ultrasound and transcutaneous electrical nerve stimulation (or US-TENS) in comparison with solely therapeutic ultrasound (US) for treatment of MPS in upper trapezius muscle. This study was a randomized single-blind placebo control trial, conducting at Sirindhorn National Medical Rehabilitaion Centre (SNMRC). The MPS patients who met the inclusion criteria of the study were randomized into two groups. Participants had received ten treatment sessions of US-TENS (intervention group) or US with sham TENS (control group) for two weeks. They were assessed for pressure pain threshold (PPT). Visual analogue scale at rest (VAS-R) and that during activity (VAS-A) on the first day and the day after ten treatment sessions were also evaluated by the blind assessor. Among 19 participants who received US-TENS showed increase of PPT by 9.6%, reduction of VAS-R and VAS-A by 57.0% and 56.2%, respectively. In control group, 20 participants had the elevation of PPT by 17.9%, decrease of VAS-R and VAS-A by 64.2% and 50.7%, respectively. However, the therapeutic tendencies between US-TENS and US were comparable by which there were no differences in average change of PPT and both VAS values (P > 0.05) between these two groups. Either US-TENS or therapeutic US was effective when being used as physiotherapy for acute and sub-acute MPS. However, there was no significant difference found between these two types of treatment.