Assessment of the acute effect of dry needling on trigger points in fibromyalgia via share wave elastography

Fibromyalgia (FM) is a characteristic rheumatic disease with widespread pain, and trigger point (TrP) accounts for 21-30% of all pain. In addition to palpation, objective criteria are needed for the diagnosis and to determine the treatment efficacy of TrPs. Dry needling (DN) is one of the preferred treatment modalities for the inactivation of these points and pain control. The aim of this study is to determine the muscle stiffness and thickness of TrPs via Shear Wave Elastography (SWE) method and to investigate the acute effect of DN on these points in FM. Demographic data of patients were recorded, then repspectively Visual Analogue Scale, Fibromyalgia Impact Questionnaire (FIQ), Nottingham Health Profile (NHP), Hospital Anxiety Depression Scale (HADS) were used to evaluate pain, physical function, quality of life and anxiety-depression risks of the individuals. TrPs were determined in the upper trapezius muscle. Muscle stiffness and thickness of both these TrPs and surrounding painless/normal tissues were measured via SWE. DN was applied to these TrPs with 0,25*25mm acupuncture needles. SWE measurement was repeated after DN. All measurements were maden three times, and the average scores were used. The functional capacity of participants was moderate (FIQ:65.21). While they complained most frequently about energy, pain, sleep problems, and their home life was adversely affected. Anxiety risks (9.83±5.27) were found higher than depression (7.76±4.89). The muscle stiffness and thickness of the right and left TrPs were higher than the normal tissue (p<0.001). The cut-off point for TrP muscle stiffness was 40.72 (sensitivity 83.02%; specificity 84.91%) on the right side, and 43.1 (sensitivity 85.19%; specificity 88.68%) on the left side. There was a significant decrease in muscle stiffness and thickness after DN of TrPs (p<0.001). In addition, a moderate correlation was recorded between right trapezius muscle stiffness and age. Consequently, it was found that the muscle stiffness and thickness of TrP, among the diagnostic criteria in FM, was higher than usual, and the cut-off point of TrP was determined. We consider that these values will make important contributions to diagnosing and to determining the effectiveness of the treatment. In addition, DN was found as an effective treatment in reducing muscle stiffness and thickness.