Effectiveness and Safety of Polydioxanone Thread Embedding Acupuncture Compared to Physical Therapy in the Treatment of Patients with Non-Specific Chronic Neck Pain: An Assessor-Blinded, Randomized, Controlled, Clinical Trial

BACKGROUND: Thread embedding acupuncture (TEA) has recently been used as a conservative treatment method for non-specific chronic neck pain (CNP). The objective of this study was to evaluate the effectiveness and safety of TEA compared to physical therapy (PT) for treating patients with CNP. METHODS: A total of 128 patients diagnosed with CNP were randomly assigned to a TEA group and a PT group at a 1:1 ratio. The TEA group received four sessions of TEA, while the PT group received eight sessions of PT over 4 weeks. Outcomes were assessed using Neck Pain and Disability Scale (NPDS), clinically important difference (CID), cervical spinal angle, Beck Depression Inventory II (BDI-II), Beck Anxiety Inventory (BAI), Patient Global Impression of Change (PGIC), and EuroQol Five-Dimension (EQ-5D) at baseline and 5, 9, and 13 weeks. RESULTS: The TEA group showed significant improvement in NPDS compared to the PT group at 5, 9, and 13 weeks. Proportions of patients with decreased NPDS scores of more than 11.5 points (minimal CID) were significantly higher in the TEA group at 5, 9, and 13 weeks. There were significant differences between the two groups at 5, 9, and 13 weeks for BDI-II, and at 5 and 9 weeks for BAI. For EQ-5D, the TEA group showed significant improvement at 5, 9, and 13 weeks. There was no significant difference in cervical spinal angle between the two groups. For PGIC, better improvement was observed at 9 and 13 weeks in the TEA group. Adverse events associated with interventions were mostly temporary and mild. CONCLUSION: For patients with CNP, TEA treatment was found to be more effective than PT treatment for improving their pain and dysfunction, quality of life, and psychological distress. Despite some post-treatment discomfort, TEA treatment can be considered as a useful treatment method for patients with CNP. TRIAL REGISTRATION: This trial has been registered 5 April 2019 in Clinical Research Information Service of South Korea (CRIS- KCT0003720).