Treatment of upper trapezius muscle myofascial pain syndrome: Comparison of ultrasound-guided dry needling techniques

Background: The aim of this study is to compare the effectiveness of ultrasound (US)-guided Superficial Dry Needling (SDN) and Deep Dry Needling (DDN) techniques in patients diagnosed with Myofascial Pain Syndrome (MPS) of the upper trapezius muscle. Materials and Methods: Eighty patients presenting with chronic neck pain and diagnosed with MPS of the upper trapezius muscle were included in the study. In this prospective, single-blind study design, the patients were randomly assigned into two groups. The SDN Group (Fascial): US-guided needles were inserted through the skin and advanced to the subcutaneous deep fascia in the region of the myofascial trigger points. The DDN Group (Myofascial): The needling procedure was applied directly to the trigger points within the muscle using a US-guided approach. In addition to the treatment, both groups were provided with a home exercise program for one week. Patients were evaluated before treatment and one week after treatment. The evaluation included Numeric Pain Rating Scale (NPRS), Neck Bournemouth Questionnaire (NBQ), and Neck Disability Index (NDI). Additionally, Cervical Range of Motion (ROM) and Algometer Pressure Pain Threshold were assessed. Results: In both techniques performed under US guidance, statistically significant changes were observed in NPRS, NBQ, NDI and pressure pain threshold measurements before and after treatment (p<0.001). In the SDN group, changes were as follows: NPRS -1.45 ± 1.13, NBQ -8.72 ± 7.22, NDI -3.8 ± 2.97, and pressure pain threshold 0.36 ± 0.39. In the DDN group, changes were: NPRS -4.22 ± 1.42, NBQ -26.12 ± 9.44, NDI -11.72 ± 3.79, and pressure pain threshold 1.23 ± 0.42. Additionally, in the DDN group, significant improvement was observed in cervical ROM in all directions (p<0.001), whereas in the SDN group, significant increases were observed only in flexion and right rotation (p<0.05). Inter-group comparisons revealed that the DDN group showed a more favorable response to the treatment across all parameters (p<0.001). Conclusion: US-guided dry needling treatment, aimed at distinguishing between superficial and deep tissues, is considered a safe and effective method in the management of upper trapezius MPS. DDN has been found to be more effective than superficial needling in terms of pain, functional status, daily living activities, and biopsychosocial outcomes. Keywords: Myofasyal Pain Syndromes, Trigger Points, Dry Needling, Ultrasonography