Effectiveness of PRP Pharmacopuncture for Chronic Neck Pain in Cervical Myofascial Syndrome of the Upper Trapezius

The goal of this clinical trial is to learn whether pharmacopuncture with Platelet-Rich Plasma (PRP) is effective for treating chronic neck pain in cervical myofascial syndrome related to the upper trapezius muscle. The main questions it aims to answer are: 1. Is pharmacopuncture with Platelet-Rich Plasma (PRP) effective in reducing chronic neck pain in patients with cervical myofascial syndrome related to the upper trapezius muscle? 2. Does PRP pharmacopuncture improve functional outcomes and quality of life in these patients? 3. Are there any adverse effects associated with PRP pharmacopuncture in this context? Researchers will compare PRP pharmacopuncture to normal saline pharmacopuncture (placebo) to evaluate whether PRP provides greater effectiveness in reducing chronic neck pain in cervical myofascial syndrome related to the upper trapezius muscle. Participants will: * Receive a single session of pharmacopuncture therapy * Undergo evaluations at week 2, week 4, and week 8 after the intervention