Contralateral Effects of Dry Needling on Upprt-trapezius Muscle Characteristics and Pain in Patients With Myofascial Pain Syndrome: A Pre-post Quasi-experimental Study

Objectives: Dry needling administered to the involved myofascial regions has demonstrated beneficial effects in managing the symptoms of myofascial pain syndrome (MPS). However, its impact on distant areas remains poorly understood. This study aimed to explore the influence of dry needling of the upper trapezius (UT) muscle on both clinical manifestations and ultrasound findings of the contralateral UT muscle in patients with MPS. Methods: Fourteen patients with MPS participated in this prepost quasi-experimental study. After the initial diagnosis of the UT muscle trigger points, pain pressure threshold and pain intensity were examined. The UT muscle was examined by ultrasound to assess thickness, blood flow, and stiffness. Participants in the study received dry needling at the UT muscle trigger point on the right side. UT muscle evaluations were performed before and after treatment on both the ipsilateral and contralateral sides. Results: The therapeutic effects of UT muscle dry needling were significant in reducing pain irritability, muscle thickness, blood flow, and stiffness on the ipsilateral side (P<۰.۰۰۱). The contralateral effects in the left UT muscle were also significant, affecting pain irritability, muscle thickness, and blood flow (P<۰.۰۰۱). Discussion: Dry needling, in addition to direct therapeutic effects on the treated area, may improve the symptoms of the UT muscle with trigger points on the contralateral side of the treatment area in patients with MPS. Therefore, contralateral dry needling may represent an alternative intervention for patients in whom direct treatment is not possible.

کلیدواژه ها:

Myofascial trigger point ، Dry needling ، Muscle stiffness ، Pain ، Ultrasonography ، Regional blood flow